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Agronomy, Volume 13, Issue 3 (March 2023) – 334 articles

Cover Story (view full-size image): The responses to water stress of six ornamental species of Asteraceae were analysed. Growth variables and biochemical stress markers were determined to assess the effects of one month of intermediate and severe stress on the plants. Multivariate analysis tools were used to rank the species according to their tolerance. Three species were relatively more susceptible to water deficit, namely, Callistephus chinensis, Xerochrysum bracteatum and Calendula officinalis, whereas Leucanthemum vulgare, Glebionis carinata and Ageratum houstonianum were more tolerant, with the last two reported as invasive. Principal component analysis (PCA) combined with canonical variation analysis (CVA) proved to be optimal statistical methods for analysing species of diverse origins and belonging to different genera of a large family, such as the Asteraceae. View this paper
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20 pages, 17708 KiB  
Article
Design and Testing of an End-Effector for Tomato Picking
by Tianchi Wang, Weiwei Du, Lingshen Zeng, Long Su, Yiming Zhao, Fang Gu, Li Liu and Qian Chi
Agronomy 2023, 13(3), 947; https://doi.org/10.3390/agronomy13030947 - 22 Mar 2023
Cited by 7 | Viewed by 1995
Abstract
Based on the structural shortage of an agricultural labor force and the continuous increase in tomato planting scale in China, as well as the limitation of a greenhouse working environment on the development of tomato picking productivity, a motor-driven end-effector for a tomato [...] Read more.
Based on the structural shortage of an agricultural labor force and the continuous increase in tomato planting scale in China, as well as the limitation of a greenhouse working environment on the development of tomato picking productivity, a motor-driven end-effector for a tomato picking robot based on a hybrid force/position control strategy was designed. First, a hybrid force/position control strategy was applied to control the picking process. Consistent with this strategy, the mechanical structure design of the end-effector was determined. The maximum torque of the finger joint motor was verified by applying a load to the end-effector fingertip under a parabolic linear angular velocity. Second, the D-H method was used to establish the end-effector single-finger and whole-hand coordinate systems and to perform forward and inverse kinematic analysis. The Monte Carlo method was used to analyze the workspace of the end-effector, and an isochronous interpolation algorithm was used to analyze the angular displacement of the motor. A basic algorithm for starting, stopping and accelerating the finger joints was designed to achieve the smooth movement of the end-effector. The control system for the end-effector was designed based on STM32F103ZET6, and the end-effector remote wireless debugging system was designed based on Tiny6410. Finally, a test prototype of the tomato picking end-effector was manufactured and picking tests were conducted, which showed that our tomato picking end-effector moved smoothly. The proposed control algorithm reduced the impact force and recorded the contact force between the end-effector and the tomato in real time, and the end-effector essentially achieved nondestructive picking. Therefore, our tomato picking end-effector demonstrated good utility in practice. Full article
(This article belongs to the Section Precision and Digital Agriculture)
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20 pages, 4850 KiB  
Article
Managing Digital Presence in Wineries Practicing Heroic Agriculture: The Cases of Ribeira Sacra and Lanzarote (Spain)
by Elena Cruz-Ruiz, F. J. Cristòfol and Gorka Zamarreño-Aramendia
Agronomy 2023, 13(3), 946; https://doi.org/10.3390/agronomy13030946 - 22 Mar 2023
Cited by 1 | Viewed by 1732
Abstract
Wine tourism has become an exciting avenue of development for rural wine-producing regions. The channels through which these millenary traditions are transmitted are diverse, and the wineries that practice heroic viticulture can sustainably influence the economic recovery process, especially after the COVID-19 crisis. [...] Read more.
Wine tourism has become an exciting avenue of development for rural wine-producing regions. The channels through which these millenary traditions are transmitted are diverse, and the wineries that practice heroic viticulture can sustainably influence the economic recovery process, especially after the COVID-19 crisis. This paper analyzes the possibilities offered by social media to promote rural territory and wine production in a sustainable way through wine tourism. For this purpose, we have used the case study of the wineries of the Ribeira Sacra appellation of origin and the Canary Islands context in the Lanzarote AO. The methodology used has counted, on the one hand, the existence of web pages of the geographical demarcations mentioned. On the other hand, a study of these wineries’ presence on the three main social networking sites, Facebook, Twitter and Instagram, has been carried out. The main focus has been on a content analysis of the social network Instagram, taking into account the terroir’s emotional values and tourist attractions. The results show that their presence on the Internet could be higher, as only 55% of the wineries of these appellations of origin have a website. In the case of Instagram, the percentages decrease in Ribeira Sacra and increase in Lanzarote. Finally, it has been possible to trace a model of rural development supported by sustainable tourism, wherein emotional values and transmitted attractions stand out, alongside elements related to the landscape and nature and the wine landscape, tradition and gastronomy. Full article
(This article belongs to the Special Issue Quality Food Chains as Opportunity for Sustainable Rural Development)
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21 pages, 10502 KiB  
Article
Integrated Proteomic and Metabolomic Analysis of Cassava cv. Kasetsart 50 Infected with Sri Lankan Cassava Mosaic Virus
by Wanwisa Siriwan, Nattachai Vannatim, Somruthai Chaowongdee, Sittiruk Roytrakul, Sawanya Charoenlappanit, Pornkanok Pongpamorn, Atchara Paemanee and Srihunsa Malichan
Agronomy 2023, 13(3), 945; https://doi.org/10.3390/agronomy13030945 - 22 Mar 2023
Cited by 4 | Viewed by 2298
Abstract
Cassava mosaic disease (CMD) is a major disease affecting cassava production in Southeast Asia. This study aimed to perform an integrated proteomics and metabolomics analysis of cassava cv. Kasetsart 50 infected with Sri Lankan cassava mosaic virus (SLCMV). Proteomics analyses revealed that 359 [...] Read more.
Cassava mosaic disease (CMD) is a major disease affecting cassava production in Southeast Asia. This study aimed to perform an integrated proteomics and metabolomics analysis of cassava cv. Kasetsart 50 infected with Sri Lankan cassava mosaic virus (SLCMV). Proteomics analyses revealed that 359 proteins were enriched in the plant–pathogen interaction, plant hormone signal transduction, and MAPK signaling pathways. A total of 79 compounds were identified by metabolomics analysis of the healthy and SLCMV-infected cassava plants. Integrated omics analysis revealed that 9 proteins and 5 metabolites were enriched in 11 KEGG pathways. The metabolic pathways, plant hormone signal transduction, and plant–pathogen interaction pathway terms were specifically investigated. The findings revealed that caffeic acid and chlorogenic acid were associated with the plant–pathogen interaction pathway, histidine (HK3) was involved in plant hormone signal transduction, while citric acid and D-serine were associated with the metabolic pathways. KEGG functional enrichment analysis revealed that plant–pathogen interaction, plant hormone signal transduction, and metabolic pathways were linked via the enriched protein (protein phosphatase 2C) and metabolites (cyclic nucleotide-binding (AT2G20050) and D-serine). The available information and resources for proteomics and metabolomics analyses of cassava can elucidate the mechanism of disease resistance and aid in cassava crop improvement programs. Full article
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16 pages, 3221 KiB  
Article
Short-Term Co-Application of Organic and Chemical Fertilizer Benefits Topsoil Properties and Maize Productivity in a Medium-Productivity Meadow-Cinnamon Soil
by Lichao Zhai, Mengjing Zheng, Lihua Zhang, Jing Chen, Jingting Zhang and Xiuling Jia
Agronomy 2023, 13(3), 944; https://doi.org/10.3390/agronomy13030944 - 22 Mar 2023
Cited by 2 | Viewed by 1616
Abstract
Co-application of organic-chemical fertilizer (CAOFCF) has attracted wide attention in China in recent years. However, its short-term effect on topsoil quality and maize yield in a medium-productivity meadow-cinnamon soil is not clear. In order to address this problem, a 3-year (2019–2021) field trial [...] Read more.
Co-application of organic-chemical fertilizer (CAOFCF) has attracted wide attention in China in recent years. However, its short-term effect on topsoil quality and maize yield in a medium-productivity meadow-cinnamon soil is not clear. In order to address this problem, a 3-year (2019–2021) field trial was established by arranging the following five treatments: (1) CF, applying chemical fertilizer alone; (2) OFCF1, 15% organic fertilizer + 85% chemical fertilizer; (3) OFCF2, 30% organic fertilizer + 70% chemical fertilizer; (4) OFCF3, 45% organic fertilizer + 55% chemical fertilizer; (5) OFCF4, 60% organic fertilizer + 40% chemical fertilizer. The results showed that short-term CAOFCF treatments were beneficial to the topsoil aggregate stability by increasing the percentage and mean weight diameter of macro-aggregate in topsoil. In addition, lower soil bulk density and higher soil organic carbon sequestration in topsoil were observed under the CAOFCF treatments. There was no difference in rhizosphere microbial diversity among all treatments. Compared to CF, OFCF1 and OFCF2 improved the activities of some key enzymes, including sucrase, urease, and acid phosphatase. Moreover, higher relative abundance of Actinobacteria and Chloroflexi were observed under the CAOFCF treatments. The root-shoot dry matter and maize grain yield were obviously higher in OFCF1 and OFCF2 than in CF; however, no significant difference was found in the OFCF3 and OFCF4 treatments compared to CF. The analysis of correlation suggested that there were no direct correlations between maize yield and various soil indexes measured. Nevertheless, root dry weight and root-shoot ratio were positively correlated with the activities of urease and sucrase. Meanwhile, the relationships between root dry weight, root-shoot ratio, shoot dry weight, and grain yield were all significant. In conclusion, short-term co-application of organic and chemical fertilizer (i.e., replacing 15–30% chemical fertilizer with organic fertilizer with an equal N rate) was beneficial to soil properties and maize grain yield in a medium-productivity meadow-cinnamon soil. The higher grain yield was associated with a strong maize root system, which was driven by the improved rhizosphere urease and sucrase activities. Full article
(This article belongs to the Special Issue Integration of Agronomic Practices for Sustainable Crop Production)
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11 pages, 2075 KiB  
Article
Parasitism Potential and Laboratory Rearing of Psyllaephagus sp., a Newly Discovered Parasitoid of Cacopsylla chinensis
by Zifang Qin, Mingyue Feng, Liu Zhang, Yang Ge, Xinzheng Huang and Wangpeng Shi
Agronomy 2023, 13(3), 943; https://doi.org/10.3390/agronomy13030943 - 22 Mar 2023
Viewed by 1360
Abstract
Psyllaephagus sp. (Hymenoptera: Encyrtidae) is a newly recognized and important parasitoid of Cacopsylla chinensis (Yang and Li) (Hemiptera: Psyllidae), a pest of pear orchards. Its parasitism potential and rearing were studied in the laboratory. The studies showed that the most suitable hosts were [...] Read more.
Psyllaephagus sp. (Hymenoptera: Encyrtidae) is a newly recognized and important parasitoid of Cacopsylla chinensis (Yang and Li) (Hemiptera: Psyllidae), a pest of pear orchards. Its parasitism potential and rearing were studied in the laboratory. The studies showed that the most suitable hosts were fourth- and fifth-instar nymphs of pear psyllids (C. chinensis). The development duration of Psyllaephagus sp. females and males was 15.25 ± 0.37 and 13.57 ± 0.27 days when laying eggs in fourth-instar psyllid nymphs. The wasps did not survive longer than three days when they were fed only water, while they survived about an average of 20 days (23.20 ± 1.12 for females and 19.00 ± 0.80 for males) when fed 20% honey water. The provision of honey water could thus increase adult parasitoid longevity significantly. The lifetime fecundity of Psyllaephagus sp. females was 21.60 ± 0.88. Tests of parasitoid efficiency showed that the wasp’s functional response was Holling type II, with the number of hosts parasitized increasing with the host density to a maximum parasitism rate. The model suggested that a single Psyllaephagus sp. female could parasitize a maximum of 13.66 nymphs per day. The mutual interference of foraging Psyllaephagus sp. females occurred at high parasitoid densities. Psyllaephagus sp. has potential as a biocontrol agent for use against C. chinensis. Full article
(This article belongs to the Section Pest and Disease Management)
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22 pages, 6096 KiB  
Article
Chemical Speciation of Trace Elements in Soil Fertilized with Biomass Combustion Ash and Their Accumulation in Winter Oilseed Rape Plants
by Małgorzata Szostek, Ewa Szpunar-Krok and Anna Ilek
Agronomy 2023, 13(3), 942; https://doi.org/10.3390/agronomy13030942 - 22 Mar 2023
Cited by 3 | Viewed by 1241
Abstract
The impact of fertilization of fly ashes from biomass combustion (BAs) on the changes in the chemical speciation of trace elements (Zn, Cu, Cr, Ni, Pb, Cd) in Gleyic Chernozem soil was analyzed in field-experiment conditions, under cultivation of winter oilseed rape plants. [...] Read more.
The impact of fertilization of fly ashes from biomass combustion (BAs) on the changes in the chemical speciation of trace elements (Zn, Cu, Cr, Ni, Pb, Cd) in Gleyic Chernozem soil was analyzed in field-experiment conditions, under cultivation of winter oilseed rape plants. The three-year field experiment was carried out in southeastern Poland (50°3′ N, 22°47′ E). The three-stage sequential extraction procedure developed by the Measurements and Testing Program (BCR) was used for the fractionation of trace elements in BAs and soil. The risk assessment code (RAC) coefficient was used to assess potential soil contamination with trace elements from Bas. The total content of Zn, Cu, Cr, Ni, Pb, and Cd in BAs used in the experiment was 470, 311, 29, 78, 38, and 3.7 mg kg−1, respectively. The present study showed that the application of BAs significantly increased the total concentration of Zn and Cu in the surface layer of the Gleyic Chernozem soil, and did not significantly increase the concentration of Cr, Ni, Pb, and Cd. Generally, using BAs does not significantly change the chemical speciation of trace elements in soil. Regardless of the applied fertilization, residual fraction (F4) was the most abundant, whereas the exchangeable/extractable (F1) fraction and reducible (F2) fraction were present in the smallest amounts. Due to the low share of exchangeable/extractable fraction (F1), the BAs used in the experiment were characterized by a low RAC coefficient; hence, their use as a soil fertilizer is relatively safe for the environment. The BAs fertilization did not cause significant changes in the content of trace elements in the different parts of the winter oilseed rape plants. Due to the relatively high content of trace elements in fly ashes from biomass combustion, an analysis of the content of individual trace element fractions should be carried out to assess their actual impact on the environment. This can help indicate further actions that should be taken to limit their negative environmental impact. Full article
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13 pages, 1493 KiB  
Article
Named Entity Recognition of Chinese Crop Diseases and Pests Based on RoBERTa-wwm with Adversarial Training
by Jianqin Liang, Daichao Li, Yiting Lin, Sheng Wu and Zongcai Huang
Agronomy 2023, 13(3), 941; https://doi.org/10.3390/agronomy13030941 - 22 Mar 2023
Cited by 7 | Viewed by 1791
Abstract
This paper proposes a novel model for named entity recognition of Chinese crop diseases and pests. The model is intended to solve the problems of uneven entity distribution, incomplete recognition of complex terms, and unclear entity boundaries. First, a robustly optimized BERT pre-training [...] Read more.
This paper proposes a novel model for named entity recognition of Chinese crop diseases and pests. The model is intended to solve the problems of uneven entity distribution, incomplete recognition of complex terms, and unclear entity boundaries. First, a robustly optimized BERT pre-training approach-whole word masking (RoBERTa-wwm) model is used to extract diseases and pests’ text semantics, acquiring dynamic word vectors to solve the problem of incomplete word recognition. Adversarial training is then introduced to address unclear boundaries of diseases and pest entities and to improve the generalization ability of models in an effective manner. The context features are obtained by the bi-directional gated recurrent unit (BiGRU) neural network. Finally, the optimal tag sequence is obtained by conditional random fields (CRF) decoding. A focal loss function is introduced to optimize conditional random fields (CRF) and thus solve the problem of unbalanced label classification in the sequence. The experimental results show that the model’s precision, recall, and F1 values on the crop diseases and pests corpus reached 89.23%, 90.90%, and 90.04%, respectively, demonstrating effectiveness at improving the accuracy of named entity recognition for Chinese crop diseases and pests. The named entity recognition model proposed in this study can provide a high-quality technical basis for downstream tasks such as crop diseases and pests knowledge graphs and question-answering systems. Full article
(This article belongs to the Special Issue Remote Sensing, GIS, and AI in Agriculture)
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12 pages, 2008 KiB  
Article
Greywater Vertical Treatment and Possibility of Reuse in the Fields from Peri-Urban Area
by Hanen Filali, Narcis Barsan, Georg Hörmann, Valentin Nedeff, Oana Irimia, Florin Nedeff and Mohamed Hachicha
Agronomy 2023, 13(3), 940; https://doi.org/10.3390/agronomy13030940 - 22 Mar 2023
Cited by 2 | Viewed by 1792
Abstract
This study highlighted the potential for greywater reuse in irrigation of olive trees. An experimental field was set up in a household of Soukra, located northwest of Tunis City, to test the performance of vertical greywater treatment. Treated greywater (TGW) was used for [...] Read more.
This study highlighted the potential for greywater reuse in irrigation of olive trees. An experimental field was set up in a household of Soukra, located northwest of Tunis City, to test the performance of vertical greywater treatment. Treated greywater (TGW) was used for the irrigation of two olive tree varieties (Chétoui and Picholine) during five years. The results show high performance of the treatment, as reflected by the good quality of TGW. The chemical and biological parameters of this TGW are under the threshold values of the Tunisian Norms of Treated Wastewaters for agriculture use (NT106.03). The BOD5 average decreased from 160.44 mg O2/L for UGW (Untreated greywater) to 15.32 mg O2/L for TGW. The COD average recorded a high reduction from 290.15 mg O2/L for UGW to 49.58 mg O2/L for TGW. The average removal rate was 90% for BOD5 and 83% for COD, proving the high performance of the treatment. The average increases in height, diameter, and olive production are significantly high for the two varieties of olive trees irrigated with treated greywater (ITGW), compared to those not irrigated and under natural conditions. In this regard, the present study has shown promising potentials for the reuse of TGW in agriculture. Full article
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14 pages, 5367 KiB  
Article
Anaerobic Soil Disinfestation Promotes Soil Microbial Stability and Antagonistic Bacteria Abundance in Greenhouse Vegetable Production Systems
by Jing Hu, Li Wan, Waqas Qasim, Haofeng Lv, Yiming Zhao, Guoyuan Li, Klaus Butterbach-Bahl and Shan Lin
Agronomy 2023, 13(3), 939; https://doi.org/10.3390/agronomy13030939 - 22 Mar 2023
Cited by 3 | Viewed by 2153
Abstract
Excessive water and fertiliser inputs, as well as long-term monocropping, not only cause resource waste and environmental pollution but also drive soil degradation and the occurrence of soil-borne diseases. Anaerobic soil disinfestation (ASD) is a widely used technique in greenhouse vegetable production to [...] Read more.
Excessive water and fertiliser inputs, as well as long-term monocropping, not only cause resource waste and environmental pollution but also drive soil degradation and the occurrence of soil-borne diseases. Anaerobic soil disinfestation (ASD) is a widely used technique in greenhouse vegetable production to replace the use of agrochemicals in disinfestation and improve product quality. While the short-term effects of ASD on the soil microbial community have been well documented in the past 15 years, only a few studies have investigated the multiseason effects of ASD, particularly on the soil microbial community composition and stability, as well as on pathogens and antagonistic microorganisms. Field experiments were conducted in three adjacent greenhouses used for tomato production for at least 20 years. Three treatments were included: CK (control: no irrigation, no plastic film covering, incorporation of chicken manure), ASD (irrigation, plastic film covering, and incorporation of rice husks), and ASD+M (ASD plus incorporation of chicken manure). Results showed that (1) ASD significantly reduced the diversity of soil bacteria and fungi and improved the complexity and stability of the soil bacterial community at the end of the ASD, but the soil microbial diversity recovered to the level before the experiment after 1.5 years. (2) Compared with CK, ASD significantly increased the relative abundance of antagonistic bacteria Bacillus, Paenibacillus and Streptomyces, decreased the relative abundance of pathogens Fusarium and the quantity of nematodes and could still effectively eliminate soil pathogens after 1.5 years. (3) Chicken manure application did not increase the pathogenic microorganisms Fusarium and nematodes, but it significantly decreased the relative abundance of antagonistic bacteria. Our results highlight that ASD not only showed an inhibitory effect on soil-borne diseases after 1.5 years but also significantly increased the relative abundance of antagonistic bacteria. However, the additional incorporation of chicken manure for ASD should be avoided due to its negative effects on the abundance of antagonistic bacteria and its contribution to environmental pollution due to N leaching and increased emissions of GHG N2O. Full article
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4 pages, 204 KiB  
Editorial
The Adaptation of Crops to the Environment under Climate Change: Physiological and Agronomic Strategies
by Rosa Porcel
Agronomy 2023, 13(3), 938; https://doi.org/10.3390/agronomy13030938 - 22 Mar 2023
Cited by 2 | Viewed by 1361
Abstract
As the world population is increasing continuously, there is a constant reduction in global arable land due to an increased demographic pressure [...] Full article
20 pages, 2043 KiB  
Article
Very Early Biomarkers Screening for Water Deficit Tolerance in Commercial Eucalyptus Clones
by Thais R. Corrêa, Edgard Augusto de T. Picoli, Washington Luiz Pereira, Samyra A. Condé, Rafael T. Resende, Marcos Deon V. de Resende, Weverton Gomes da Costa, Cosme Damião Cruz and Edival Angelo V. Zauza
Agronomy 2023, 13(3), 937; https://doi.org/10.3390/agronomy13030937 - 22 Mar 2023
Cited by 6 | Viewed by 1754
Abstract
The identification of genotypes more tolerant to water deficit is a challenge to breeding programs. In this research, our objectives were to identify and validate traits for tolerance to water deficit in eucalypts. The estimation of genotypic parameters and early selection are proposed [...] Read more.
The identification of genotypes more tolerant to water deficit is a challenge to breeding programs. In this research, our objectives were to identify and validate traits for tolerance to water deficit in eucalypts. The estimation of genotypic parameters and early selection are proposed based on mixed models, selection indexes and validation schemes. Seedlings with 110 days were grown in a greenhouse for 12 weeks, and two water deficit treatments were conducted (polyethylene glycol and water limitation). A total of 26 biomarkers were evaluated, and 15 of them were significant, exhibited adequate heritability, and used for screening: final plant height, increment in height, increment in diameter, area of mature and fully expanded leaf, nutrient contents of N, K, Ca, Mg, S, Cu, Zn, Mn and B, photosynthesis (A) and stomatal conductance (gs). Both treatments were adequate to discriminate water deficit-tolerant clones. The ranking of tolerant clones according to their phenotype in the field demonstrates the potential for early selection and is consistent with the maintenance of water-deficit-tolerance mechanisms until adulthood. There is evidence that the choice of biomarker depends on the species involved and different strategies contributing to the tolerance trait. Full article
(This article belongs to the Special Issue Photosynthetic Adaptability of Crops under Environmental Change)
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13 pages, 4183 KiB  
Article
Identification and Analysis of the Catalase Gene Family Response to Abiotic Stress in Nicotiana tabacum L.
by Zhonghui Liu, Di Wang, Heng Tang, Haozhen Li, Xiaohua Zhang, Shaolin Dong, Li Zhang and Long Yang
Agronomy 2023, 13(3), 936; https://doi.org/10.3390/agronomy13030936 - 22 Mar 2023
Cited by 5 | Viewed by 1766
Abstract
Catalase (CAT) is an enzyme encoded by the catalase gene family that plays an important role in the removal of reactive oxygen species. In this study, seven CAT genes were identified in Nicotiana tabacum L. and were classified into three groups. Gene structure [...] Read more.
Catalase (CAT) is an enzyme encoded by the catalase gene family that plays an important role in the removal of reactive oxygen species. In this study, seven CAT genes were identified in Nicotiana tabacum L. and were classified into three groups. Gene structure analysis revealed that NtCAT1–6 has six or seven introns while NtCAT7 only contains one. The relative position of introns in NtCAT1 and NtCAT2 had high similarity. Tissue-specific analysis shows that NtCAT1–4 were expressed intensively in the shoot while NtCAT5 and NtCAT6 were in the root. NtCAT7 expression was influenced by circadian rhythms. NtCATs expression had the greatest change under drought stress. Additionally, expression of NtCAT5, NtCAT6 and NtCAT7 were upregulated under cold stress but downregulated under drought and salt stress. This study will help in understanding the behavior of CAT genes during environmental stress in tobacco. Full article
(This article belongs to the Special Issue Genetic Analysis in Crops)
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23 pages, 5879 KiB  
Article
Integration Vis-NIR Spectroscopy and Artificial Intelligence to Predict Some Soil Parameters in Arid Region: A Case Study of Wadi Elkobaneyya, South Egypt
by Moatez A. El-Sayed, Alaa H. Abd-Elazem, Ali R. A. Moursy, Elsayed Said Mohamed, Dmitry E. Kucher and Mohamed E. Fadl
Agronomy 2023, 13(3), 935; https://doi.org/10.3390/agronomy13030935 - 21 Mar 2023
Cited by 6 | Viewed by 2425
Abstract
Understanding and determining soil properties is reflected in improving farm management and crop production. Soil salinity, pH and calcium carbonate are among the factors affecting the soil’s physical and chemical properties. Hence, their estimation is very important for agricultural management, especially in arid [...] Read more.
Understanding and determining soil properties is reflected in improving farm management and crop production. Soil salinity, pH and calcium carbonate are among the factors affecting the soil’s physical and chemical properties. Hence, their estimation is very important for agricultural management, especially in arid regions (Wadi Elkobaneyya valley, located in the northwest of Aswan Governorate, Upper Egypt). The study objectives were to characterize and develop prediction models for soil salinity, pH and calcium carbonate (CaCO3) using integration soil analysis and spectral reflectance vis-NIR spectroscopy. To achieve the study objectives, three multivariate regression models: Partial Least Squares Regression (PLSR), Multivariate Adaptive Regression Splines (MARS) and Least Square-Support Vector Regression (LS-SVR)); and two machine learning algorithms, Random Forest (RF) and Artificial Neural Networks (ANN) were used. Ninety-six surface soil samples were collected from the study area at depths 0–5 cm. The data were divided into a calibration dataset (70% of the total) and a validation dataset (30% of the total dataset). The obtained results represent that the PLSR model was the best model for soil pH parameters where R2 of calibration and validation predictability = 0.68 and 0.52, respectively. The LS-SVR model was the best model to predict soil Electrical Conductivity (EC) and soil Calcium Carbonate (CaCO3) content, with R2 0.70 and 0.74 for calibration and R2 0.26 and 0.47 for validation, respectively. On the other hand, the results of the implemented machine learning algorithm model showed that RF was the best model to predict soil pH and CaCO3, as the R2 was 0.82 for calibration and 0.57 for validation, respectively. Nevertheless, the best model for predicting soil EC was ANN, with an R2 of 0.96 for calibration and 64 for validation. The results show the advantages of machine learning models for predicting soil EC, pH and CaCO3 by Vis-NIR spectroscopy. Therefore, Vis-NIR spectroscopy is considered faster and more cost-efficient and can be further used in environmental monitoring and precision farming. Full article
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20 pages, 5522 KiB  
Article
Deep Learning for Detecting and Classifying the Growth Stages of Consolida regalis Weeds on Fields
by Abeer M. Almalky and Khaled R. Ahmed
Agronomy 2023, 13(3), 934; https://doi.org/10.3390/agronomy13030934 - 21 Mar 2023
Cited by 5 | Viewed by 2248
Abstract
Due to the massive surge in the world population, the agriculture cycle expansion is necessary to accommodate the anticipated demand. However, this expansion is challenged by weed invasion, a detrimental factor for agricultural production and quality. Therefore, an accurate, automatic, low-cost, environment-friendly, and [...] Read more.
Due to the massive surge in the world population, the agriculture cycle expansion is necessary to accommodate the anticipated demand. However, this expansion is challenged by weed invasion, a detrimental factor for agricultural production and quality. Therefore, an accurate, automatic, low-cost, environment-friendly, and real-time weed detection technique is required to control weeds on fields. Furthermore, automating the weed classification process according to growth stages is crucial for using appropriate weed controlling techniques, which represents a gap of research. The main focus of the undertaken research described in this paper is on providing a feasibility study for the agriculture community using recent deep-learning models to address this gap of research on classification of weed growth stages. For this paper we used a drone to collect a dataset of four weed (Consolida regalis) growth stages. In addition, we developed and trained one-stage and two-stage models YOLOv5, RetinaNet (with Resnet-101-FPN, Resnet-50-FPN backbones) and Faster R-CNN (with Resnet-101-DC5, Resnet-101-FPN, Resnet-50-FPN backbones), respectively. The results show that the generated Yolov5-small model succeeds in detecting weeds and classifying weed growth stages in real time with the highest recall of 0.794. RetinaNet with ResNet-101-FPN backbone shows accurate results in the testing phase (average precision of 87.457). Although Yolov5-large showed the highest precision in classifying almost all weed growth stages, Yolov5-large could not detect all objects in tested images. Overall, RetinaNet with ResNet-101-FPN backbones shows accurate and high precision, whereas Yolov5-small shows the shortest inference time in real time for detecting a weed and classifying its growth stages. Full article
(This article belongs to the Special Issue Machine Vision Systems in Digital Agriculture)
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22 pages, 9388 KiB  
Article
Spectral Quantitative Analysis and Research of Fusarium Head Blight Infection Degree in Wheat Canopy Visible Areas
by Yanyu Chen, Xiaochan Wang, Xiaolei Zhang, Ye Sun, Haiyan Sun, Dezhi Wang and Xin Xu
Agronomy 2023, 13(3), 933; https://doi.org/10.3390/agronomy13030933 - 21 Mar 2023
Cited by 2 | Viewed by 1560
Abstract
Obtaining complete and consistent spectral images of wheat ears in the visible areas of in situ wheat canopies poses a significant challenge due to the varying growth posture of wheat. Nevertheless, detecting the presence and degree of wheat Fusarium head blight (FHB) in [...] Read more.
Obtaining complete and consistent spectral images of wheat ears in the visible areas of in situ wheat canopies poses a significant challenge due to the varying growth posture of wheat. Nevertheless, detecting the presence and degree of wheat Fusarium head blight (FHB) in situ is critical for formulating measures that ensure stable grain production and supply while promoting green development in agriculture. In this study, a spectral quantitative analysis model was developed to evaluate the infection degree of FHB in an in situ wheat canopy’s visible areas. To achieve this, a spectral acquisition method was used to evaluate the infection degree of FHB in a wheat canopy’s visible areas. Hyperspectral images were utilized to obtain spectral data from healthy and mildly, moderately, and severely infected wheat ear canopies. The spectral data were preprocessed, and characteristic wavelengths were extracted using twelve types of spectral preprocessing methods and four types of characteristic wavelength extraction methods. Subsequently, sixty-five spectral quantitative prediction models for the infection degree of FHB in the in situ wheat canopy visible areas were established using the PLSR method, based on the original spectral data, preprocessed spectral data, original spectral characteristic wavelengths extracted data, and preprocessed spectral characteristic wavelengths extracted data. Comparative analysis of the models indicated that the MMS + CARS + PLSR model exhibited the best prediction effect and could serve as the spectral quantitative analysis model for the evaluation of the infection degree of FHB in an in situ wheat canopy’s visible areas. The model extracted thirty-five characteristic wavelengths, with a modeling set coefficient of determination (R2) of 0.9490 and a root-mean-square error (RMSE) of 0.2384. The testing set of the coefficient of determination (R2) was 0.9312, with a root-mean-square error (RMSE) of 0.2588. The model can facilitate the spectral quantitative analysis of the infection degree of FHB in the in situ wheat canopy visible areas, thereby aiding in the implementation of China’s targeted poverty alleviation and agricultural power strategy. Full article
(This article belongs to the Special Issue AI, Sensors and Robotics for Smart Agriculture)
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16 pages, 2968 KiB  
Article
Assessment of Photoperiod Sensitivity and the Effect of Sowing Date on Dry-Season Sorghum Cultivars in Southern Chad
by Gapili Naoura, Yves Emendack, Nerbéwendé Sawadogo, Nadjiam Djirabaye, Ramadjita Tabo, Haydee Laza and Eyanawa A. Atchozou
Agronomy 2023, 13(3), 932; https://doi.org/10.3390/agronomy13030932 - 21 Mar 2023
Cited by 3 | Viewed by 1527
Abstract
The cultivation of dry-season sorghum on residual moisture in West and Central Africa is highly affected by sowing dates and ecotypes used. Fifty-five dry-season sorghum ecotypes collected from three zones in southern Chadian were sown on two dates, early and late, in 2013 [...] Read more.
The cultivation of dry-season sorghum on residual moisture in West and Central Africa is highly affected by sowing dates and ecotypes used. Fifty-five dry-season sorghum ecotypes collected from three zones in southern Chadian were sown on two dates, early and late, in 2013 and 2014, in an α-Lattice, and replicated five times to evaluate the effect of sowing date on potential yield, flowering time, and other agro-morphological traits and to determine their photoperiod sensitivity. Trials were conducted in the research fields at the Agricultural Research Extension Farm in Youé, Chad. Year, sowing date, and their interaction significantly affected most of the assessed traits. Delaying sowing significantly decreased potential yield, duration of vegetative phase, and other agro-morphological traits, except staygreen. All cultivars were photoperiodic with late sowing requiring a lower cumulative growing degree unit to flower. The flowering window was not affected by sowing dates across cultivars; however, the flowering time was affected by a decrease in daylength, but not low night temperatures. Generally, late sowing decreased potential yield across cultivars. However, this decrease varied with the region of origin, with seven cultivars having average potential yields at or above the regional potential yield of 1 t/ha, irrespective of year or sowing dates. Full article
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23 pages, 1487 KiB  
Review
Industrial Hemp (Cannabis sativa L.) Agronomy and Utilization: A Review
by Jelena Visković, Valtcho D. Zheljazkov, Vladimir Sikora, Jay Noller, Dragana Latković, Cynthia M. Ocamb and Anamarija Koren
Agronomy 2023, 13(3), 931; https://doi.org/10.3390/agronomy13030931 - 21 Mar 2023
Cited by 43 | Viewed by 17467
Abstract
Currently, there are increased interests in growing grain and fiber hemp (Cannabis sativa L.) as well as in large-scale hemp products. Cannabis has been grown/utilized for thousands of years as a fiber, grain, and drug/medicinal plant. However, the strict control of cannabis [...] Read more.
Currently, there are increased interests in growing grain and fiber hemp (Cannabis sativa L.) as well as in large-scale hemp products. Cannabis has been grown/utilized for thousands of years as a fiber, grain, and drug/medicinal plant. However, the strict control of cannabis cultivation to combat illegal use, the spread of new yarns and oilseeds, and the advent of cheap synthetic fibers caused a decreased/eliminated hemp production. Hemp has been banned in most of the world for more than seven decades; it missed out on the Green Revolution and the adoption of new technologies and varieties, creating a knowledge gap. After the 2014 and 2018 Farm Bill in the USA, hemp became legal and the land grand universities launched research programs. The ability to utilize the entire plant for multiple purposes creates opportunity for the market to value hemp products. Hemp production technology varies depending on the type of hemp cultivated (grain, fiber, or cannabinoids), soil characteristics, and environmental factors. Hemp has the potential to be a very sustainable and ecologically benign crop. Hemp roots have a significant potential for absorbing and storing heavy metals such as lead, nickel, cadmium, and other harmful substances. In addition, hemp has been proven to be an excellent carbon trap and biofuel crop. Hemp has the ability to successfully suppress weeds, and it is generally regarded a pesticide-free crop. The purpose of this paper is to examine historic and recent industrial hemp (grain and fiber) literature, with a focus on hemp agronomy and utilization. Full article
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24 pages, 1567 KiB  
Article
Individual and Interactive Ecophysiological Effect of Temperature, Watering Regime and Abscisic Acid on the Growth and Development of Tomato Seedlings
by Taghleb Al-Deeb, Mohammad Abo Gamar, Sabah Khaleel, Abdul Latief Al-Ghzawi, Wesam Al Khateeb, Mohammad Jawarneh, Mohammad Y. Jahmani, Omar Al-Zoubi and Talaat Habeeb
Agronomy 2023, 13(3), 930; https://doi.org/10.3390/agronomy13030930 - 21 Mar 2023
Cited by 1 | Viewed by 2593
Abstract
Climate change is a major concern to people all over the world. Most studies have considered singular or dual effects of climate change implications on plant growth and development; however, the combination of multiple factors has received little attention. We therefore studied the [...] Read more.
Climate change is a major concern to people all over the world. Most studies have considered singular or dual effects of climate change implications on plant growth and development; however, the combination of multiple factors has received little attention. We therefore studied the single and combined effects of two environmental stress factors (high temperature and water stresses) and abscisic acid on tomato seedlings (Solanum lycoperscum L.). Plants were grown in controlled environment growth chambers under two temperatures (22/18 °C or 28/24 °C; 16 h light/8 h dark), two watering regimes (well-watered or water-stressed), and two abscisic acid treatments (0 and 100 µL of 1mM abscisic acid solution, every other day). Plants were placed under experimental conditions for a total of 33 days, including a 13-day period of initial growth and hardening. Morphological, biochemical, and physiological parameters were measured to assess the growth and development of plants in response to the three factors. ANOVA and Scheffé’s multiple-comparison procedures were used to establish significant differences among treatments and among the three factors being manipulated. All three factors decreased plant height and growth rate. Dry mass accumulation was negatively affected by high temperatures. Transpiration, stomatal conductance, and gas exchange parameters were negatively affected by all three factors; additionally, net carbon dioxide assimilation was reduced by water stress and abscisic acid application. Non-photochemical quenching was decreased in plants grown under higher temperature and in abscisic acid-treated plants. Though it was not significant, abscisic acid appears to mitigate the negative effect of higher temperature and water stress on the nitrogen balance index and total chlorophyll content. Full article
(This article belongs to the Section Horticultural and Floricultural Crops)
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16 pages, 1486 KiB  
Article
Agronomic, Economic and Environmental Comparative of Different Aeration Systems for On-Farm Composting
by Víctor Valverde-Orozco, Irene Gavilanes-Terán, Julio Idrovo-Novillo, Lourdes Carrera-Beltrán, Cristian Basantes-Cascante, Maria Angeles Bustamante and Concepción Paredes
Agronomy 2023, 13(3), 929; https://doi.org/10.3390/agronomy13030929 - 21 Mar 2023
Cited by 2 | Viewed by 1996
Abstract
On-farm composting of agro-livestock wastes can be considered the most appropriate method for their recycling. Pile turning (PW) is one of the most widely used aeration systems for composting. However, this system has long composting periods and is inefficient at supplying oxygen and [...] Read more.
On-farm composting of agro-livestock wastes can be considered the most appropriate method for their recycling. Pile turning (PW) is one of the most widely used aeration systems for composting. However, this system has long composting periods and is inefficient at supplying oxygen and controlling the temperature. To minimize these drawbacks, the combination of turnings with forced aeration (PR) is an option; in this work, this combination was compared to PW as an aeration system for the co-composting of vegetable waste with different manures. In this comparative study, the evolution of the process, the compost quality and the economic and environmental impacts of the process were evaluated. The PR system was more appropriate for obtaining sanitized composts (the temperature was ≥55 °C for at least three consecutive days) with an adequate degree of maturity. Furthermore, this system reduced the organic matter and nutrient losses, yielding composts with higher agronomic value and a higher total combined value of the nutrients than those obtained using the PW system. However, the energy consumption and associated CO2 emissions were lower for the PW system, since this aeration system was based only on turnings without the use of forced aeration, as in the case of the PR system. Agricultural valorization of composts will offset this energy consumption and its impact, since it will contribute to reducing the use of synthetic fertilizers. However, more studies are required on the PR composting system and other agro-livestock wastes for the creation of centralized on-farm composting sites, where all steps of the composting chain are optimized. Full article
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17 pages, 6787 KiB  
Article
Improving Wheat Yield and Phosphorus Use Efficiency through the Optimization of Phosphorus Fertilizer Types Based on Soil P Pool Characteristics in Calcareous and Non-Calcareous Soil
by Laichao Luo, Xinyao Zhang, Min Zhang, Peng Wei, Rushan Chai, Yayi Wang, Chaochun Zhang and Kadambot H. M. Siddique
Agronomy 2023, 13(3), 928; https://doi.org/10.3390/agronomy13030928 - 21 Mar 2023
Cited by 7 | Viewed by 2545
Abstract
Irrational phosphorus (P) nutrient management practices often fail to match of P fertilizer type, soil P transformation and crop P demand, lead to increased accumulation of legacy P, reduced PUE, and pollution, affecting crop production. A pot experiment incorporating soil types and P [...] Read more.
Irrational phosphorus (P) nutrient management practices often fail to match of P fertilizer type, soil P transformation and crop P demand, lead to increased accumulation of legacy P, reduced PUE, and pollution, affecting crop production. A pot experiment incorporating soil types and P fertilizer types (SSP, simple superphosphate; CMP, calcium magnesium phosphate; DAP, diammonium phosphate; TSP, triple superphosphate; APP, ammonium polyphosphate; CK, no P application) to establish coupling of the soil and P fertilizer types, soil P pool characteristics, crop P uptake. In calcareous soil, the available P concentrations in rhizosphere soil were higher under TSP and DAP, with the increase in NaHCO3-Pi concentration the most. In non-calcareous soil, the NaHCO3-Pi and NaOH-Pi increased the most under SSP, DAP, and TSP at anthesis. Shoot P accumulation at maturity was highest under TSP and APP, TSP and DAP, respectively, in the two soil. TSP and APP significantly increased yield and PUE in the calcareous soil, while TSP and DAP performed better in the non-calcareous soil. NaHCO3-Pi and NaOH-Po are potentially available P sources in calcareous and non-calcareous soil, which remarkably affect shoot P uptake through H2O-P. Comprehensive assessment of the relationship between soil P pool characteristics, yield and PUE, TSP and APP are recommended for application in calcareous soils and TSP and DAP for application in non-calcareous soils in wheat cropping systems. Full article
(This article belongs to the Section Soil and Plant Nutrition)
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17 pages, 3058 KiB  
Article
Response of Soybean Yield and Certain Growth Parameters to Simulated Reproductive Structure Removal
by Sarah Kezar, Anna Ballagh, Vanaja Kankarla, Sumit Sharma, Raedan Sharry and Josh Lofton
Agronomy 2023, 13(3), 927; https://doi.org/10.3390/agronomy13030927 - 21 Mar 2023
Cited by 7 | Viewed by 2188
Abstract
Soybeans often encounter several in-season stressors that can alter retention of reproductive structures. To understand soybean response to structural losses through altered growth parameters—and, ultimately, yield—a field trial was established in Bixby, Oklahoma, in 2019 and 2020 and Perkins, Oklahoma, in 2019. Removal [...] Read more.
Soybeans often encounter several in-season stressors that can alter retention of reproductive structures. To understand soybean response to structural losses through altered growth parameters—and, ultimately, yield—a field trial was established in Bixby, Oklahoma, in 2019 and 2020 and Perkins, Oklahoma, in 2019. Removal of reproductive structures occurred at full flower (R2), the beginning of pod development (R3), and the beginning of seed development (R5) and at three locations on the plant (top third (T), middle third (M), whole (W)). The impact of flower removal on yield at the R2 and R3 stages did not significantly differ from that in non-treated soybean. Pod removal as late as R5 from the upper fruiting positions (T) had a lesser impact on overall yield, with R5:T showing a reduction in seed number of 860 seeds plant−1, whereas R5:M was 1921 seeds plant−1 below the non-treated soybean. The middle portion of the mainstem was the location where the loss demonstrated was paramount at R5, as this region is a large sink and major contributor to yield. Late-season, stress-negating yield recovery, depending on the severity, may indicate that management practices should anticipate physiological limitations for stress, as well as the potential for relative yield recovery and yield improvement. Full article
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19 pages, 4661 KiB  
Article
Effect of Plastic Film Colours and Perforations on Energy Distribution, Soil Temperature, and Evaporation
by Zunqiu Xu, Rony Wallach, Jian Song and Xiaomin Mao
Agronomy 2023, 13(3), 926; https://doi.org/10.3390/agronomy13030926 - 21 Mar 2023
Cited by 2 | Viewed by 1626
Abstract
Plastic film mulching is a commonly used agricultural measure in arid/cold regions to improve crop growth. Despite previous studies on the impact of film mulching on soil water/heat status and crop growth, it is not clear how plastic film colours and perforations affect [...] Read more.
Plastic film mulching is a commonly used agricultural measure in arid/cold regions to improve crop growth. Despite previous studies on the impact of film mulching on soil water/heat status and crop growth, it is not clear how plastic film colours and perforations affect energy distribution, soil temperature, and evaporation. Six sets of column experiments were performed with three plastic film colours: transparent (T), black (B), and silver-grey (G), and two perforation ratios: 4.49% and 21.44%, to monitor soil evaporation and soil/film mulching temperature. Using these two main control factors, a soil–mulch–atmosphere system (SMAS) model was established to simulate soil evaporation and energy distribution. The simulations of soil evaporation compared well with the measurements. The available net energy was positively related to the perforation ratio and transmittance of the plastic film, which further influenced soil temperature and altered energy distribution. Both simulated and measured results gave the following order for transpiration with the plastic films: T > B > G. The SMAS model was more accurate when a mulch with weak light transmittance covered the field. Moreover, by comparing simulated evaporation mass loss with and without considering heat conduction between the plastic mulch and the soil surface, Csm, we found that it is feasible to exclude Csm. However, Csm is indispensable in the SMAS model for understanding the mechanism of plastic film mulching in agroecosystems, particularly at night. Full article
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22 pages, 11120 KiB  
Article
Selection of a Navigation Strategy According to Agricultural Scenarios and Sensor Data Integrity
by Leonardo Bonacini, Mário Luiz Tronco, Vitor Akihiro Hisano Higuti, Andres Eduardo Baquero Velasquez, Mateus Valverde Gasparino, Handel Emanuel Natividade Peres, Rodrigo Praxedes de Oliveira, Vivian Suzano Medeiros, Rouverson Pereira da Silva and Marcelo Becker
Agronomy 2023, 13(3), 925; https://doi.org/10.3390/agronomy13030925 - 21 Mar 2023
Cited by 1 | Viewed by 1515
Abstract
In digital farming, the use of technology to increase agricultural production through automated tasks has recently integrated the development of AgBots for more reliable data collection using autonomous navigation. These AgBots are equipped with various sensors such as GNSS, cameras, and LiDAR, but [...] Read more.
In digital farming, the use of technology to increase agricultural production through automated tasks has recently integrated the development of AgBots for more reliable data collection using autonomous navigation. These AgBots are equipped with various sensors such as GNSS, cameras, and LiDAR, but these sensors can be prone to limitations such as low accuracy for under-canopy navigation with GNSS, sensitivity to outdoor lighting and platform vibration with cameras, and LiDAR occlusion issues. In order to address these limitations and ensure robust autonomous navigation, this paper presents a sensor selection methodology based on the identification of environmental conditions using sensor data. Through the extraction of features from GNSS, images, and point clouds, we are able to determine the feasibility of using each sensor and create a selection vector indicating its viability. Our results demonstrate that the proposed methodology effectively selects between the use of cameras or LiDAR within crops and GNSS outside of crops, at least 87% of the time. The main problem found is that, in the transition from inside to outside and from outside to inside the crop, GNSS features take 20 s to adapt. We compare a variety of classification algorithms in terms of performance and computational cost and the results show that our method has higher performance and lower computational cost. Overall, this methodology allows for the low-cost selection of the most suitable sensor for a given agricultural environment. Full article
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13 pages, 10976 KiB  
Article
Phytolith Content Negatively Affects Forage Quality of Eragrostis curvula (Schrad.) Nees
by Jimena Gallardo, Marina Díaz, José Carballo, Antonio Garayalde and Viviana Echenique
Agronomy 2023, 13(3), 924; https://doi.org/10.3390/agronomy13030924 - 21 Mar 2023
Viewed by 1739
Abstract
Phytoliths are intra and extracellular siliceous deposits present in different plant tissues. Si uptake and transport are mediated by Lsi genes and its concentration is associated with forage quality. Our objective was to determine the phytolith content in seven Eragrostis curvula genotypes at [...] Read more.
Phytoliths are intra and extracellular siliceous deposits present in different plant tissues. Si uptake and transport are mediated by Lsi genes and its concentration is associated with forage quality. Our objective was to determine the phytolith content in seven Eragrostis curvula genotypes at the outbreak and re-growth stages to assess its relationship with the forage quality parameters and perform a genome-wide analysis to detect the presence/absence of Lsi genes. The mean values of the phytolith content of dry matter varied between 1.94–2.26% and 2.72–4.71% at the outbreak and re-growth stages, respectively, with highly significant differences among the genotypes and phenological stages. A highly negative correlation was observed in the phytolith content and in vitro dry matter digestibility and crude protein, revealing its importance as a selection parameter in breeding programs. A positive correlation was obtained between the phytolith content and lignin, neutral detergent fiber, and acid detergent fiber. The main morphotypes of the phytoliths included saddle-shaped, bulliform, and acicular cells. Genes Lsi1, Lsi2, Lsi3, and Lsi6, previously reported in silica uptake, were identified and compared with related species, being the gene sequences highly conserved, meaning that its accumulation is probably due to differences in the gene expression or different allelic variants among cultivars. Full article
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13 pages, 2188 KiB  
Article
Leaf Trait Hyperspectral Characterization of Castanea sativa Miller Affected by Dryocosmus kuriphilus Yasumatsu
by Dimas Pereira-Obaya, Fernando Castedo-Dorado, Enoc Sanz-Ablanedo, Karen Brigitte Mejía-Correal and José Ramón Rodríguez-Pérez
Agronomy 2023, 13(3), 923; https://doi.org/10.3390/agronomy13030923 - 20 Mar 2023
Cited by 1 | Viewed by 1435
Abstract
While populations of the Asian chestnut gall wasp (Dryocosmus kuriphilus Yasumatsu), an invasive pest affecting the European chestnut (Castanea sativa Miller), have started to be controlled biologically, this pest still conditions chestnut tree development. With the aim of assessing plant health [...] Read more.
While populations of the Asian chestnut gall wasp (Dryocosmus kuriphilus Yasumatsu), an invasive pest affecting the European chestnut (Castanea sativa Miller), have started to be controlled biologically, this pest still conditions chestnut tree development. With the aim of assessing plant health status as a means of monitoring gall wasp infestation, we used a field spectroradiometer to collect data from leaves taken from 83 trees in two chestnut orchards. We calculated characteristic spectral signatures for pest infestation, and after training and validation, developed classifiers to distinguish between different infestation levels. Several partial least square discriminant analysis (PLS-DA) and random forest (RF) models were fitted with reflectance and transformed values to obtain characteristic curves reflecting infestation. Four wavelengths (560 nm, 680 nm, 1400 nm, and 1935 nm) were identified as showing the greatest differences between curves. The best overall accuracy (69.23%) was achieved by an RF model fitted with reflectance transformed values. Lower overall accuracy (26.92%) was achieved in distinguishing between infestation levels. In conclusion, while more specific differences in infestation levels were not detectable, our method successfully discriminated between gall absence and presence. Full article
(This article belongs to the Special Issue Advances in Field Spectroscopy in Agriculture)
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18 pages, 41139 KiB  
Article
How to Efficiently Produce the Selenium-Enriched Cucumber Fruit with High Yield and Qualities via Hydroponic Cultivation? The Balance between Selenium Supply and CO2 Fertilization
by Ziying Wang, Di Li, Nazim S. Gruda, Chunwu Zhu, Zengqiang Duan and Xun Li
Agronomy 2023, 13(3), 922; https://doi.org/10.3390/agronomy13030922 - 20 Mar 2023
Cited by 2 | Viewed by 1631
Abstract
Hydroponic-producing selenium (Se)-biofortified vegetables in a greenhouse is a convenient and effective way to provide Se-enriched food and overcome hidden hunger. CO2 fertilization is commonly implemented to increase vegetable yield in greenhouse production. However, this application accompanies decreased mineral concentrations in the [...] Read more.
Hydroponic-producing selenium (Se)-biofortified vegetables in a greenhouse is a convenient and effective way to provide Se-enriched food and overcome hidden hunger. CO2 fertilization is commonly implemented to increase vegetable yield in greenhouse production. However, this application accompanies decreased mineral concentrations in the edible parts. Here we investigated the effects of [CO2] and Se supply on the growth, gas exchange, and cucumber fruit quality. A hydroponic experiment with two CO2 concentrations ([CO2]) (C1: 410, and C2: 1200 μmol mol−1) and four Se supply levels (Se0: 0, Se1: 0.125, Se2: 0.250, and Se3: 0.500 mg Se L−1) was carried out. A low level of Se supply (Se1: 0.125 mg Se L−1) protected the photosynthetic pigments and stimulated the stomatal opening, especially under [CO2] fertilization. It leads to a higher net photosynthesis rate (Pn) and transpiration rate (Tr) than other Se treatments. The most significant changes in dry weight, fruit yield, and soluble sugar concentration were also obtained in Se1 under CO2 fertilization due to the enhanced CO2 fixation. Meanwhile, the Se concentration in fruit was 0.63 mg kg−1 FW in C2Se1, with the highest Se accumulation and use efficiency. According to the recommended dietary allowance of 55 μg Se day−1 for adults, an intake of 87 g of cucumber grown in C2Se1 is sufficient. Because of the improved Tr and better root structure in Se1, the uptake of mineral nutrients through mass flow and interception was well maintained under CO2 fertilization. So, the concentrations of N, P, K, Ca, and Mn in cucumber fruits were not significantly decreased by elevated [CO2] in Se1. However, the concentrations of soluble proteins, S, Mg, Fe, and Zn in cucumber fruits in C2Se1 were lower than those in C1Se1, which was mainly attributed to the dilution effects under CO2 fertilization. Therefore, a selenite supply of 0.125 mg Se L−1 was found to be the optimal dosage for producing Se-enriched cucumber fruits with high yield and better qualities under CO2 fertilization (1200 μmol mol−1). Full article
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14 pages, 2498 KiB  
Article
Properties of Biochar Obtained from Tropical Crop Wastes Under Different Pyrolysis Temperatures and Its Application on Acidic Soil
by Shuhui Song, Ping Cong, Chao Wang, Puwang Li, Siru Liu, Zuyu He, Chuang Zhou, Yunhao Liu and Ziming Yang
Agronomy 2023, 13(3), 921; https://doi.org/10.3390/agronomy13030921 - 20 Mar 2023
Cited by 9 | Viewed by 1768
Abstract
When biochars are produced, feedstock is a crucial factor that determines their physicochemical properties. However, the characteristics of tropical crop waste-derived biochar have not been described and limit its availability. In this study, pineapple leaf (PAL), banana stem (BAS), sugarcane bagasse (SCB) and [...] Read more.
When biochars are produced, feedstock is a crucial factor that determines their physicochemical properties. However, the characteristics of tropical crop waste-derived biochar have not been described and limit its availability. In this study, pineapple leaf (PAL), banana stem (BAS), sugarcane bagasse (SCB) and horticultural substrate (HCS), were used to prepare biochar at 300, 500 and 700 °C. Properties of biochars and their applications were analysed. The results indicated that hydrophobicity, nonpolarity and aromaticity of SCB biochar (SCBB) were higher than other biochars due to the loss of H (hydrogen), O (oxygen), and N (nitrogen). The pH of PAL biochar (PALB) and BAS biochar (BASB) ranged from 9.69 to 10.30 higher than that of SCBB and HCS biochar (HCSB) with 7.17–9.77. In PALB and BASB, sylvite was the dominant crystal structure. With temperature rising, C–H stretching, C=C stretching and H–O in alcohol groups decreased, and Si–O stretching in HCSB and SCBB strengthened. Biochars obtained at 500 °C, especially SCBB and HCSB, significantly promoted the growth of maize. The PALB and BASB greatly increased the soil pH/EC to 6.90–7.35 and 0.67–0.95 ms/cm, while those of SCBB and HCSB were 5.97–6.74 and 0.23–0.45 ms/cm. The application of the biochars to the soil increased soil pH, reducing the acidic soil stress in maize growth, especially PAL and BAS biochars prepared at 300 °C. Biochar prepared at lower temperature will greatly reduce energy consumption and increase the utilization efficiency of tropical agricultural waste resources. Full article
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20 pages, 3402 KiB  
Article
Bibliometric Analysis on the Impact of Climate Change on Crop Pest and Disease
by Qiliang Yang, Tianmu Du, Na Li, Jiaping Liang, Tehseen Javed, Haidong Wang, Jinjin Guo and Yanwei Liu
Agronomy 2023, 13(3), 920; https://doi.org/10.3390/agronomy13030920 - 20 Mar 2023
Cited by 5 | Viewed by 2947
Abstract
Affected by global warming, the frequency of crop pests and diseases have increased, causing huge losses to agricultural production. To better grasp the development and trends of research on the effects of climate change on crop pests and diseases, the literature on the [...] Read more.
Affected by global warming, the frequency of crop pests and diseases have increased, causing huge losses to agricultural production. To better grasp the development and trends of research on the effects of climate change on crop pests and diseases, the literature on the impact of climate change on crop pests and diseases published from 1990 to 2021 in the Web of Science (WOS) core collection database was used. This study explores the literature characteristics and hotspot evolution through the bibliometric visualization analysis software COOC, VOSviewer, and CiteSpace, with a view to identifying the changing characteristics and trends of research changes in this field. The results showed that the number of literature on the impact of climate change on crop pests and diseases increased rapidly. The main fields involved include environmental sciences, ecology, and agronomy. Papers in these fields mainly published in journals, such as PLos One, Forest Ecology and Management, and Frontiers in Plant Science. The country with the highest number of publications was the United States, followed by China and Australia. The most prolific authors in the top 20 are research scholars from China. The first author of the top 20 highly cited papers was from the United States. It was found that that current research on the impact of climate change on crop pests and diseases mainly focuses on agricultural production and food safety. Modelling and crop growth has maintained steady development. At present, research in this field mainly focuses on pest management strategies under the impact of climate change, the response of single species, and the complex ecological mechanisms behind the response. This study provides unique insights into the research field of the impact of climate change on crop pests and diseases and provides a reference direction for future research development in this field. Full article
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15 pages, 3294 KiB  
Article
Genetic Diversity in Oilseed and Vegetable Mustard (Brassica juncea L.) Accessions Revealed by Nuclear and Mitochondrial Molecular Markers
by Dongsuo Zhang, Haibo Yu, Lianliang Gao, Jing Wang, Hui Dong, Yuan Guo and Shengwu Hu
Agronomy 2023, 13(3), 919; https://doi.org/10.3390/agronomy13030919 - 20 Mar 2023
Cited by 2 | Viewed by 2161
Abstract
Genetic diversity analysis is a fundamental work for effective management and utilization of plant germplasm. Brassica juncea is an economically important crop, including both oilseed and vegetable types. In the present study, a total of 99 accessions of Brassicaceae family, including 84 mustard (50 [...] Read more.
Genetic diversity analysis is a fundamental work for effective management and utilization of plant germplasm. Brassica juncea is an economically important crop, including both oilseed and vegetable types. In the present study, a total of 99 accessions of Brassicaceae family, including 84 mustard (50 oilseed and 34 vegetable types) in China and 15 other Brassicaceae accessions were evaluated for their genetic diversity using nuclear and mitochondrial molecular markers. All accessions were evaluated using 18 simple sequence repeats, 20 sequence related amplified polymorphisms, and 7 intron-exon splice junction primers, and in total, 232 polymorphic fragments were obtained. The unweighted pair-group method with arithmetic mean cluster analysis indicated that all accessions could be divided into three major clusters, with cluster I including all 50 oilseed mustard, cluster II including 34 vegetable mustard, and cluster III containing 15 other Brassicaceae accessions. The results of principal component analysis and population structure analysis were in accordance with the cluster result. Molecular variance analysis revealed that the genetic variation was 34.07% among populations and 65.93% within Brassica species, which indicates existence of considerable genetic variation among oilseed and vegetable B. juncea species. Based on an InDel and a SNP locus reported in B. juncea mitochondrial genome, all the 84 B. juncea mitochondrial genomes were divided into three mitotypes (MTs1-3), 22 accessions of MT1, 20 accessions of MT2, and 42 accessions of MT3. In addition, the results of the modified multiplex PCR, Indel and SNP could identify pol-, cam-, nap- (or MT4), Bol-, Bni-, Esa-, and In-cytoplasmic types in 15 other Brassicaceae accessions. Together, oilseed and vegetable B. juncea can be used for broadening the genetic background for each other. Full article
(This article belongs to the Special Issue Application of Molecular Marker Technology in Crop Breeding)
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18 pages, 1065 KiB  
Article
Effects of Goat Manure Fertilization on Grain Nutritional Value in Two Contrasting Quinoa (Chenopodium quinoa Willd.) Varieties Cultivated at High Altitudes
by J. A. González, Sawsan K. M. Yousif, L. E. Erazzu, L. Martínez Calsina, E. F. Lizarraga, Rihab M. Omer, D. Bazile, J. L. Fernandez-Turiel, S. E. Buedo, M. Rejas, P. D. Fontana, D. A. González, A. Oviedo, Fahad Mohammed Alzuaibr, Salem Mesfer Al-Qahtani, Nadi Awad Al-Harbi, Mohamed F. M. Ibrahim and C. P. Van Nieuwenhove
Agronomy 2023, 13(3), 918; https://doi.org/10.3390/agronomy13030918 - 20 Mar 2023
Cited by 3 | Viewed by 3699
Abstract
In this study, the effects of goat manure fertilization (2, 4, 8, and 12 Tn/ha) on the grain yield, organic compounds, and mineral composition of two quinoa varieties (CICA-17 and Regalona Baer) were evaluated under field conditions in Northwest Argentina. The results indicate [...] Read more.
In this study, the effects of goat manure fertilization (2, 4, 8, and 12 Tn/ha) on the grain yield, organic compounds, and mineral composition of two quinoa varieties (CICA-17 and Regalona Baer) were evaluated under field conditions in Northwest Argentina. The results indicate that fertilization improved the quinoa grain yield and total protein content. Low manure doses positively affected the fatty acid (FA) profile, and significant changes were determined for the monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acid contents of CICA-17 and on the saturated fatty acid (SFA) contents of R. Baer seeds. The amino acid contents were positively affected in CICA-17 and negatively in R. Baer. Soluble sugars (glucose, fructose, and sucrose), major elements (K, Si, P, Mg, Ca, and Na), minor elements (Fe, Mn, Al, Zn, and Cu), and ultratrace elements (Cr and Li) were detected and discussed in terms of their impact on human nutrition and health. Conclusively, manure addition affected some essential amino acids, the desaturase activity, the n6:n3 and SFA/UFA ratios, the atherogenic index, soluble sugars, and mineral content, and the fatty acid metabolism of each variety was differently affected, especially the C16 and C18 desaturase activity, which responded differently to various manure doses. Manure addition is a promising alternative to improve the nutritional quality and functionality of quinoa grains, but the response is not linear. Full article
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