Search Results (42)

Drought stress is a critical abiotic constraint on agricultural productivity, particularly affecting crops like pepper (Capsicum annuum L.), which are highly susceptible to water deficits due to their physiological characteristics. The present study investigated the impact of a 40% reduction in irrigation on yield, macronutrient concentrations, and fruit quality across several pepper genotypes. The cultivars evaluated included two landraces, namely ‘JO109’ and ‘JO204’ (Capsicum annuum var. grossum), as well as the California cultivar ‘Yolo Wonder’ and the commercial F1 hybrid ‘Sammy RZ’, which served as controls. The experiment was conducted at the greenhouse facilities of the Laboratory of Vegetable Production, Agricultural University of Athens. Under reduced irrigation, most of the cultivars studied exhibited a decline in yield, which was attributed to a decrease in fruit number in ‘Yolo Wonder’ and a reduction in fruit weight in both ‘JO204’ and ‘Sammy’. In contrast, the landrace ‘JO109’ exhibited consistent yields under both growing conditions, a response likely attributed to elevated K concentration in the leaves and lower Na accumulation in the fruit, indicating enhanced tolerance to water deficit. A decline in leaf K concentration was observed in response to drought stress, while concomitantly increased concentrations of Na, Ca and Mg were recorded. Among fruit macronutrients, only Ca showed a significant decrease under reduced irrigation. Furthermore, fruit firmness (FF), titratable acidity (TA) and total soluble solids content (TSSC) exhibited higher levels under drought stress, particularly in ‘JO109’, while TA remained unaltered. These findings highlight the potential of landraces such as ‘JO109’ to be utilized in breeding programs aimed at enhancing resilience, while maintaining pepper fruit quality under limited water availability. Full article

Mineral nutrition management in sweet cherry orchards remains a critical challenge due to the lack of site-specific fertilization guidelines, particularly in Greece, a significant cherry-producing country. This study aimed to develop a predictive framework for total nutrient losses in sweet cherry orchards by proposing simplified estimations using fresh fruit yield as the sole input variable. Field experiments were conducted in two orchards with distinct rootstocks (MxM 14 and CAB-6P), analyzing soil properties, leaf nutrient status, and uptake patterns on different plant components. Results indicated that despite differences in soil texture and pH, nutrient availability was generally sufficient, with only Fe and Zn marginally below optimal levels in leaf tissue. Principal Component Analysis (PCA) revealed distinct nutrient distribution patterns, with N evenly distributed across fruits, peduncles, and prunings, while K was concentrated in fruits and peduncles, and Ca and Mg predominantly in fallen leaves. Notably, K was redistributed from leaves to fruits under high yields, evidenced by negative correlations between leaf biomass and K uptake. Strong relationships (r² > 0.8) were found between fresh fruit yield and uptake of N, P, K, Mg, B, and Cu, enabling reliable predictions of total nutrient losses. Estimated annual nutrient removals were 85.6 kg ha⁻¹ N, 8.94 kg ha⁻¹ P, 42.7 kg ha⁻¹ K, and 12.0 kg ha⁻¹ Mg, with significant fractions retained in prunings and fallen leaves (e.g., 51.8 kg ha⁻¹ N, 6.2 kg ha⁻¹ P). The developed yield-based models provide a practical tool for optimizing fertilization strategies, while our findings highlight the potential for nutrient recycling through sustainable residue management. Full article

Combretum micranthum G. Don (kinkeliba) is a medicinal plant traditionally employed in West Africa for its diuretic and gastrointestinal therapeutic properties. Despite its extensive ethnomedicinal use, comprehensive toxicological assessments are still lacking. This study aimed to characterize the phenolic composition of C. micranthum ethanolic leaf extract using HPLC-DAD-ESI-MS and evaluate its acute and subacute oral toxicity in BALB/c mice, per OECD Guideline 420. Female mice received oral doses of 50, 300, and 2000 mg/kg of extract for acute toxicity assessment for 14 days. In the subacute study, both sexes were administered daily doses at the same concentrations over 28 days. Clinical signs, body weight, and food and water consumption were regularly monitored throughout both protocols. At the end of each study, hematological, biochemical, and histopathological parameters were analyzed. Phenolic profiling revealed nine major compounds with a total of 293.54 mg/g extract. No mortality or significant clinical manifestations were observed at any dose. However, significant variations in platelet counts and amylase activity were noted in the acute phase. In the subacute model, slight, non-critical alterations in hepatic and renal biomarkers were observed, without signs of systemic toxicity. Histopathological examination revealed similar lesions in both acute and subacute phases, including multifocal inflammatory infiltrates (lymphocytes and neutrophils) in the periportal area of the liver, minimal bacterial overgrowth in the superficial layer of the gastric mucosa, minimal medullary mineralization and inflammatory infiltrates with lymphocytes in the kidneys, and minimal to moderate vacuolization in the pancreatic acini. These results indicate that C. micranthum ethanolic extract is relatively safe at the tested doses, reinforcing its traditional use and supporting further research into its pharmacological potential. Full article

The production of fruit crops plays a vital role in the agricultural sector, contributing significantly to the social and economic development of rural communities. In Brazil, fruit production is diverse due to favorable edaphoclimatic conditions, with avocado (Persea americana Mill.) emerging as an important crop. Its production continues to expand in both cultivated areas and yield, making it a key export to non-producing countries. However, despite its importance, nutritional management information, crucial for achieving high yields, remains limited. Current guidelines on nutrition monitoring are outdated, general, and based on data from other countries with different edaphoclimatic conditions, making them not directly applicable to Brazilian orchards. Furthermore, outdated nutritional information becomes less reliable over time, as climate change alters soil conditions and crop nutrient concentrations and requirements, reinforcing the need for the establishment of up-to-date and specific nutritional information. This study aimed to establish nutritional standards for ‘Hass’ avocado production using the Diagnosis and Recommendation Integrated System (DRIS) and Compositional Nutrient Diagnosis (CND) methodologies, and to define sufficiency ranges (SRs) and Critical Levels (CLs) for both macronutrients (N, P, K, Ca, Mg, and S) and micronutrients (B, Cu, Fe, Mn, and Zn). The analyses were based on yield (t ha⁻¹) and leaf nutrient content data from commercial orchards, with datasets divided into younger (4–9 years) and older (10–26 years) plant groups. The DRIS effectively established nutritional standards for younger plants, explaining 11% of yield variation through nutritional balance. CND, in turn, was effective for both groups, accounting for 14% of yield variation and outperforming DRIS in associating nutritional status with productivity. SRs and CLs for ‘Hass’ avocado production were defined using both DRIS and CND. Together, these indices and diagnostic parameters offer valuable tools for enhancing nutritional monitoring and fertilization strategies in Brazil. Notably, SRs and CLs varied according to plant age. Full article

Tissue culture-based rapid propagation is critical for genetic improvement and virus-free production of strawberries (Fragaria × ananassa). This study evaluated the optimal concentration of thidiazuron (TDZ) for shoot multiplication and explored the underlying molecular mechanisms. Strawberry explants were treated with TDZ at concentrations of 0, 0.025, 0.05, 0.1, and 0.4 mg·L⁻¹ in vitro, and growth, physiological changes, and transcriptomic profiles were analyzed after four weeks. The results identified 0.05 mg·L⁻¹ TDZ as the most effective concentration for shoot proliferation, yielding a significant increase in leaf number. However, TDZ application inhibited plant height and reduced chlorophyll, carotenoid, and soluble sugar contents. Physiological analyses revealed that TDZ decreased endogenous cytokinin levels while elevating auxin concentrations. Transcriptomic analysis showed that TDZ suppressed cytokinin biosynthesis and up-regulated cytokinin oxidase expression, thereby modulating hormone homeostasis. Additionally, TDZ enhanced the cytokinin signaling pathway, which is crucial for cell division and shoot initiation, and influenced auxin, gibberellin, and brassinosteroid pathways to regulate differentiation. These findings suggest that TDZ promotes strawberry shoot multiplication primarily through hormone signal transduction, providing insights for optimizing tissue culture protocols. Full article

Extraction is one of the most important phases in the food, pharmaceutical, and nutraceutical industries, as it enables the isolation of valuable compounds from raw materials. Ipomoea batatas L. leaf extract has anti-diabetic qualities due to anthocyanidins, flavonols, flavanones, and phenolic acids. The goal of this study is to maximize extraction on a production scale with total flavonoids and fingerprint profiles that closely resemble standardized extracts. In this study, extraction was performed using the percolator method with optimization parameters, including ethanol concentration (40, 50, 60, and 70%) and wetting time (0.5, 3, and 24 h). Quality control in extraction was assessed through the total flavonoids and fingerprint analysis. TLC was used to determine the fingerprints of Ipomoea batatas L. leaf extract, followed by multivariate analysis. Using 60% ethanol and 3 h of wetting time produced total flavonoids of 19.86 ± 0.2 mg quercetin/g and a fingerprint close to the control with a similarity of 94.87%. Ethanol concentration and wetting time are critical parameters in Ipomoea batatas L. extraction. Quality control through total flavonoid determination and fingerprint analysis during the extraction process provides a standardized approach to maintain the quality, safety, and efficacy of Ipomoea batatas L. natural products. Full article

This study examines the variations of elements in PM_2.5 emitted from biomass burning in urban settings, which raises health concerns among urban dwellers. It specifically focused on how Sodium (Na), Calcium (Ca), Potassium (K), and Phosphorus (P) concentrations in tree combustibles affect their concentrations in PM_2.5 emitted during combustion. Understanding these interactions is critical for evaluating air quality and its public health effects. Urban landscape coniferous and broad-leaf tree species combustibles (branches and leaves) were assessed, and the data were processed using Microsoft Excel, Origin Pro 2024, and R Studio. It was discovered that the species and organs had a common elemental concentration pattern (Ca > K > P > Na) in their combustibles but a different concentration pattern in the emitted PM_2.5. Quantitatively, the concentrations in the combustibles varied, with Ca being the most abundant (69.85 mg/kg) and P the least (3.97 mg/kg). In PM_2.5, the contrary was observed, i.e., Na (which was among the least concentrated elements in the combustibles) became prominent; the highest levels were recorded in PM_2.5 from conifers (Na = 0.86 mg/kg). Among the assessed elements in PM_2.5, P had the lowest concentration in all the tests, having the lowest values from broad-leaf species (P = 0.02 mg/kg). The SEM result further revealed that, quantitatively, the concentration of these elements in the combustibles does not necessarily mean that they will be in higher concentrations in the emitted PM_2.5. These variations highlighted the importance of considering tree species, organ types, and elemental interactions when assessing the impacts of biomass combustion on urban air quality and human health. Full article

Rapid urbanization and increasing land scarcity have made urban agriculture and efficient space utilization critical directions in modern agriculture. Ougan, a fruit tree valued for both its economic and ecological benefits, holds significant promise for dwarfing cultivation techniques. In this study, a root-irrigation method was used to apply paclobutrazol at various concentrations (200, 500, 1000, 1500, and 2000 mg/L) to Ougan seedlings, with a control group for comparison. Growth parameters include an average daily increase of plant height, stem girth, new branches, and new branch girth, as well as physiological indices such as leaf SPAD values, leaf nitrogen content, net photosynthetic rate, stomatal conductance, intercellular CO₂ concentration, and transpiration rate, were measured during both spring and summer growth periods. The results demonstrate that PBZ exerts a distinct concentration-dependent regulatory effect on Ougan growth: higher concentrations significantly inhibited plant height while promoting increases in stem diameter, with several parameters exhibiting a unimodal response. Short-term (spring) PBZ application enhanced certain photosynthetic parameters, such as net photosynthetic rate and stomatal conductance; however, prolonged exposure (summer) resulted in a decline in photosynthetic efficiency and overall leaf physiological status. Through comprehensive evaluation using principal component analysis and PLS-SEM, the 500 mg/L PBZ treatment was identified as achieving the optimal balance between growth inhibition and the maintenance of photosynthetic and nutritional status, closely approximating the ideal dwarfing effect. This study elucidates the complex regulatory effects of PBZ on the growth, photosynthesis, and carbon assimilation of Ougan through natural climate, providing robust technical parameters and theoretical support for future dwarf cultivation practices. These findings facilitate the development of dwarf fruit trees into bonsai vegetation, demonstrating significant horticultural application potential. Full article

In natural saline habitats, the impact of the salt-ion content absorbed by halophytes on their biomass development remains unclear. This research investigated Poacynum pictum (Schrenk) Baill., a typical halophyte in the Ebinur Lake Wetland Reserve. P. pictum was collected from three water–salt habitats: high water and high salt (Habitat 1), medium water and medium salt (Habitat 2), and low water and low salt (Habitat 3). This study aimed to quantify the salt-ion content and biomass in different P. pictum organs, analyze their distribution under varying water–salt habitats, and explore the mechanism of the relationship between salt-ion content and biomass. The results showed the following: (1) With the decrease in water–salt habitats, the Na⁺ contents of aboveground organs decreased, whereas root Na⁺ content increased. The aboveground organs’ Ca²⁺ contents exhibited the ranking Habitat 2 > Habitat 3 > Habitat 1. The Ca²⁺ and Mg²⁺ contents followed a similar pattern, with leaves showing the highest concentrations, and the Ca²⁺ and Mg²⁺ contents in roots exhibited a declining trend with the decrease in water–salt habitats. The Cl⁻ content was predominant in the leaves and stems of all water–salt habitats. This indicates that P. pictum can maintain an ionic state in the body and resist habitat stress through the separation and absorption of salt ions in different organs. (2) With the decrease in water–salt habitats, the leaf, twig, stem, and total biomass of P. pictum demonstrated a gradually decreasing trend, and the root biomass initially increased and then decreased. This reveals that P. pictum can adapt to high–saline habitats and achieve normal growth and development, and that suitable water and salt conditions are important for underground accumulation. (3) The Na⁺ content in leaves, twigs, and stems had a significant positive effect on the biomass of these organs, making it the most influential factor, and the root biomass was primarily affected by root Ca²⁺. These findings indicate that P. pictum adapted to saline habitats by adjusting its ion uptake and biomass, and the Na⁺ in aboveground organs and Ca²⁺ in roots are critical for biomass development in their respective organs. This study provides valuable insights into the adaptation strategies of halophytes in salinized environments and highlights the importance of specific ions’ accumulation for biomass maintenance. Full article

The evaluation of plant responses to water deficit in the substrate, particularly in the context of intensifying climate change, represents a critical factor for ensuring stable agricultural production, economic resilience, and food security. The primary objective of this study was to compare the physiological and biochemical responses to water deficit in conventional cultivation of Fragaria vesca plants propagated both in vitro and in vivo. The research encompassed measurements of gas exchange parameters, chlorophyll “a” fluorescence, photosynthetic pigment and proline content in leaves, leaf relative water content index, total fruit yield, single fruit weight, fresh and dry mass of the root system, as well as the concentrations of K, Ca, Mg, Na, Cu, Zn, Mn, and Mo. Additionally, the ratio of monovalent to divalent cations in leaves, roots, and crowns was analyzed. The results revealed significant differences between the experimental variants under optimal conditions and their respective responses to drought stress. Plants derived from in vitro cultures, despite exhibiting initially lower physiological trait values, demonstrated higher yield potential (no significant difference in the yield of fresh fruit mass compared to a 78% reduction). However, a long-term lack of water caused greater damage to their photosynthetic system—a reduction in physiological traits to 80% was observed, compared to a maximum decrease of 40% in plants derived from seedlings. The results highlight that environmental conditions and the acclimatization process of plants derived from in vitro cultures can significantly influence their adaptive potential and productivity. Full article

Direct somatic embryogenesis represents a fundamental tool for obtaining genetically homogeneous clones; however, its commercial scaling faces critical challenges at various stages of the process. In this study, a protocol is standardized for the induction and germination of somatic embryos from leaf segments, rooting, and acclimatization of four Coffea arabica hybrids: Casiopea, Excelencia, H3, and Milenio. The results show that the Casiopea and Excelencia hybrids achieve the highest induction rates (71.64% and 74.43%) and embryo production (8.74 and 10) per explant in the M1 medium, while these values are significantly lower for H3 and Milenio. In addition, the germination and conversion of embryos into plantlets are more efficient in the woody plant medium (WPM), while rooting is optimized using indole-3-butyric acid (IBA) concentrations between 1 mg L⁻¹ and 3 mg L⁻¹, regardless of the hybrid. During the acclimatization phase, plantlets treated with mycorrhizae exhibit improved morphological, physiological, and nutritional indicators, achieving a superior quality according to the Dickson index. These findings significantly reduce production times by establishing precise standards for each genotype, thereby overcoming existing gaps in production protocols and providing a solid foundation for industrial growth. Full article

In saline conditions, establishing healthy seedlings is crucial for the productivity of sunflowers (Helianthus annuus L.). Excessive potassium (K⁺) from irrigation water or overfertilization, similar to sodium (Na⁺), could adversely affect sunflower growth. However, the effects of salt stress caused by varying K/Na ratios on the establishment of sunflower seedlings have not been widely studied. We conducted a pot experiment in a greenhouse, altering the K/Na ratio of a soil solution to grow sunflower seedlings. We tested three saline solutions with K/Na ratios of 0:1 (P0S1), 1:1 (P1S1), and 1:0 (P1S0) at a constant concentration of 4 dS m⁻¹, along with a control (CK, no salt added), with five replicates. The solutions were applied to the pots via capillary rise through small holes at the bottom. The results indicate that different K/Na ratios significantly influenced ion-selective uptake and transport in crop organs. With an increasing K/Na ratio, the K⁺ concentration in the roots, stems, and leaves increased, while the Na⁺ concentration decreased in the roots and stems, with no significant differences in the leaves. Furthermore, an excessive K/Na ratio (P1S0) suppressed the absorption and transportation of Mg²⁺, significantly reducing the Mg²⁺ concentration in the stems and leaves. A lower leaf Mg²⁺ concentration reduced chlorophyll concentration, impairing photosynthetic performance. The lowest plant height, leaf area, dry matter, and shoot/root ratio were observed in P1S0, with reductions of 27%, 48%, 48%, and 13% compared to CK, respectively. Compared with CK, light use efficiency and CO₂ use efficiency in P1S0 were significantly reduced by 13% and 10%, respectively, while water use efficiency was significantly increased by 9%. Additionally, improved crop morphological and photosynthetic performance was observed in P1S1 and P0S1 compared with P1S0. These findings underscore the critical role of optimizing ion composition in soil solutions, especially during the sensitive seedling stage, to enhance photosynthesis and ultimately to improve the plant’s establishment. We recommend that agricultural practices in saline regions incorporate tailored irrigation and fertilization strategies that prioritize optimal K/Na ratios to maximize crop performance and sustainability. Full article

Despite quinoa (Chenopodium quinoa Willd.) gaining international popularity in the early 21st century for its nutritional benefits, there remains a critical need to optimize its cultivation practices in arid regions. Current research often overlooks the combined effects of supplemental irrigation and foliar treatments on quinoa’s yield and water efficiency, particularly under challenging environmental conditions like those in Borg El-Arab, Egypt. Field studies were conducted in Borg El-Arab, Alexandria, Egypt, during the winter seasons of 2021/2022 and 2022/2023 to determine the influence of supplemental irrigation (rainfed, 2000, and 4000 m³/hectare, respectively) and foliar spraying of sodium silicate (control, 200, and 400 ppm) on yield, yield components, seed quality, and water usage efficiency in quinoa cv. Chibaya grown in arid lands. Three replications were used in a split-plot design. The main plots were designated for irrigation, while the subplots were designated for foliar spraying. The results indicate that applying irrigation at a rate of 4000 m³/hectare significantly increased leaf dry weight per plant by 23.5%, stem dry weight per plant by 18.7%, total dry weight per 25 plants by 21.4%, leaf area per plant by 19.2%, and straw yield by 26.8% compared to the control treatment. There were no significant differences between irrigation with the rate of 4000 m³ or 2000 m³/hectare on biological yield kg/hectare, N (%), P (mg/100 g), and protein (%). The utilization of sodium silicate had no significance on all studied features except for straw yield kg ha⁻¹ at the rate of 200 or 400 ppm. The results regarding the RAPD1 primer revealed that the 2000+0 silicon treatment was the only treatment that resemble the control with no up- or downregulated fragment. Moreover, 20 upregulated fragments were observed in all treatments, while 19 DNA fragments were downregulated. Furthermore, the results obtained regarding the RAPD2 primer revealed that 53 fragments were upregulated and 19 downregulated. Additionally, the RAPD3 primer demonstrated that 40 DNA fragments were upregulated, whereas 18 downregulated DNA fragments were detected. It may be inferred that the application of irrigation at a rate of 4000 m3 ha⁻¹ might serve as a supplemental irrigation method. Spraying sodium silicate at a 400 mg L⁻¹ concentration could alleviate the dry climate on the Egyptian shore. Full article

Genetic transformation of forest trees is essential for validating gene functions and breeding new varieties through molecular means. Appropriate selective pressure is critical for creating an effective screening system. ‘Beilinxiongzhu 1’ sensitivity testing showed that the critical tolerance concentrations for hygromycin (Hyg), kanamycin (Kan), and glyphosate (PPT) in leaf explants were 2.0 mg/L, 20 mg/L, and 1.0 mg/L, respectively. Among the physiological indicators, soluble sugar content, soluble protein content, and endogenous hormone levels were identified as key markers of the effects of the different antibiotic treatments. Transcriptome analysis showed that Hyg treatment resulted in a large number of differentially expressed genes (DEGs) involved in leaf cell wall synthesis and glucose metabolism. Under Kan treatment, the DEGs were associated with pathways such as ribosome biosynthesis and histone packaging in eukaryotes. Under PPT treatment, significant DEGs were related to ABC transporters. DEGs common to all three antibiotics were involved in glutathione metabolism pathways. A weighted gene co-expression network analysis identified TRXH2, H3.2, H2B, GST, U71K1, and CHS as key genes in response to antibiotic stress. By elucidating the physiological and molecular mechanisms by which different antibiotics affect leaf sprouting, our study serves as a reference for research into the genetic transformation of poplar leaves. Full article

One of the key factors for sustainability in agricultural systems, particularly, for cultivation of date palms, is the identification of the performance parameters of the pollen grains of male date palms (Phoenix dactylifera L.). This study was carried out to predict the performance parameters of pollen grains using an artificial neural network (ANN) model. The morphological features of spathe length, spathe weight, number of pinnae per leaf, leaf length, leaf width, length of the pinna part, pinna length, pinna width, length of the spathe stem, and spathe width, as well as the concentrations of minerals such as Mg, N, K, P, and Ca in their leaves were used as inputs to the ANN model. For this purpose, we collected the required data from nine male date palms grown in Saudi Arabia. The ANN model utilized in this work included an input layer with 15 parameters, a hidden layer of 30 neurons, and an output layer with 8 neurons. The ANN model was trained with 27 patterns. Seven patterns were utilized for testing purposes. The coefficient of determination (R²) obtained between the observed and predicted performance parameters’ values using the testing dataset was 0.902 for the number of strands per spathe, 0.967 for strand length, 0.963 for the number of flowers per strand, 0.941 for the number of flowers per spathe, 0.985 for the weight of pollen grains per spathe, 0.810 for the pollen grains’ viability, 0.936 for the pollen grains’ length, and 0.992 for the pollen grains’ width. The length of the spathe stem had the most critical effect on how the ANN model predicted the values of the dependent variables, i.e., the number of strands per spathe, with a percentage of contribution of 17.66%; the weight of pollen grains per spathe, with 17.85%; the pollen grains’ length, with 19.78%, and the pollen grains’ width, with a percentage of contribution of 30.59%. Spathe weight had the most critical influence on strand length and pollen grains’ viability, with percentages of 26.29% and 14.92%, respectively. Leaf width had the most critical effect on the number of flowers per spathe, with a percentage of 12.55%. The elemental concentration of K in the male date palm leaves had the most critical effect on the number of flowers per strand, with a percentage of 13.98%. It was therefore concluded that using a modeling process with the ANN technique can help estimate the performance parameters of male date palms’ pollen grains for different purposes, such as providing a starting point for mathematical analyses associated with the physiological mechanisms of male date palm. Moreover, the outcomes of this research work can be supportive as a practical tool in this field of study. Full article