Search Results (11)

Peanut (Arachis hypogea L.) crops in the southeastern U.S. suffer significant yield losses from diseases like leaf spot, southern blight, and stem rot. Traditionally, growers use conventional boom sprayers, which often leads to overuse and wastage of agrochemicals. However, advances in computer technologies have enabled the development of precision or variable-rate sprayers, both ground-based and drone-based, that apply agrochemicals more accurately. Historically, crop disease scouting has been labor-intensive and costly. Recent innovations in computer vision, artificial intelligence (AI), and remote sensing have transformed disease identification and scouting, making the process more efficient and economical. Over the past decade, numerous studies have focused on developing technologies for peanut disease scouting and sprayer technology. The current research trend shows significant advancements in precision spraying technologies, facilitating smart spraying capabilities. These advancements include the use of various platforms, such as ground-based and unmanned aerial vehicle (UAV)-based systems, equipped with sensors like RGB (red–blue–green), multispectral, thermal, hyperspectral, light detection and ranging (LiDAR), and other innovative detection technologies, as highlighted in this review. However, despite the availability of some commercial precision sprayers, their effectiveness is limited in managing certain peanut diseases, such as white mold, because the disease affects the roots, and the chemicals often remain in the canopy, failing to reach the soil where treatment is needed. The review concludes that further advances are necessary to develop more precise sprayers that can meet the needs of large-scale farmers and significantly enhance production outcomes. Overall, this review paper aims to provide a review of smart spraying techniques, estimating the required agrochemicals and applying them precisely in peanut fields. Full article

Subtilases (SBTs), known as serine proteases or phytoproteases in plants, are crucial enzymes involved in plant development, growth, and signaling pathways. Despite their recognized importance in other plant species, information regarding their functional roles in cultivated peanut (Arachis hypogea L.) remains sparse. We identified 122 AhSBT genes in the STQ peanut genome, classifying them into six subgroups based on phylogenetic analysis. Detailed structural and motif analyses revealed the presence of conserved domains, highlighting the evolutionary conservation of AhSBTs. The collinearity results indicate that the A. hypogea SBT gene family has 17, 5, and 1 homologous gene pairs with Glycine max, Arabidopsis thaliana, and Zea mays, respectively. Furthermore, the prediction of cis-elements in promoters indicates that they are mainly associated with hormones and abiotic stress. GO and KEGG analyses showed that many AhSBTs are important in stress response. Based on transcriptome datasets, some genes, such as AhSBT2, AhSBT18, AhSBT19, AhSBT60, AhSBT102, AhSBT5, AhSBT111, and AhSBT113, showed remarkably higher expression in diverse tissues/organs, i.e., embryo, root, and leaf, potentially implicating them in seed development. Likewise, only a few genes, including AhSBT1, AhSBT39, AhSBT53, AhSBT92, and AhSBT115, were upregulated under abiotic stress (drought and cold) and phytohormone (ethylene, abscisic acid, paclobutrazol, brassinolide, and salicylic acid) treatments. Upon inoculation with Ralstonia solanacearum, the expression levels of AhSBT39, AhSBT50, AhSBT92, and AhSBT115 were upregulated in disease-resistant and downregulated in disease-susceptible varieties. qRT-PCR-based expression profiling presented the parallel expression trends as generated from transcriptome datasets. The comprehensive dataset generated in the study provides valuable insights into understanding the functional roles of AhSBTs, paving the way for potential applications in crop improvement. These findings deepen our understanding of peanut molecular biology and offer new strategies for enhancing stress tolerance and other agronomically important traits. Full article

In peanut cultivation in the Tokachi region of Hokkaido, Japan, it is essential to complete the harvest by early October to prevent frost damage. Therefore, cultivation methods that can accelerate the flowering period are necessary. It is understood that planting density can influence the timing of flowering, with crops often flowering earlier at higher densities. This study aimed to investigate whether growing peanuts at higher densities could advance the flowering period and, consequently, enhance yield. The Japanese peanut variety, Tachimasari, was cultivated in 2022 and 2023 at a conventional planting density of 5.8 plant m⁻² (D5.8) and at density conditions of 8.7 plant m⁻² (D8.7) and 11.6 plant m⁻² (D11.6). The D8.7 and D11.6 plants reached the peak of flowering 2.8 and 5.1 days earlier, respectively, and the end of flowering 3.7 and 8.0 days earlier than the D5.8 plants. Although the total number of flowers was higher in D5.8, pod fertility was greater in D8.7 and D11.6, where plants were able to reduce the occurrence of ineffective flowers and immature pods. Consequently, higher seed yields were observed in D8.7 (2709 kg ha⁻¹) and D11.6 (2754 kg ha⁻¹), where lower individual productivity was offset by higher planting densities, compared to the conventional density condition of D5.8 (2169 kg ha⁻¹). Full article

The lateral organ boundaries domain (LBD) genes, as the plant-specific transcription factor family, play a crucial role in controlling plant architecture and stress tolerance. However, the functions of AhLBD genes in the peanut plant (Arachis hypogea L.) remain unclear. In this study, 73 AhLBDs were identified in the peanut plant and divided into three groups by phylogenetic tree analysis. Gene structure and conserved protein motif analysis supported the evolutionary conservation of AhLBDs. Tandem and segment duplications contributed to the expansion of AhLBDs. The evolutionary relationship analysis of LBD gene family between A. hypogaea and four other species indicated that the peanut plant had a close relationship with the soybean plant. AhLBDs played a very important role in response to growth and development as well as abiotic stress. Furthermore, gene expression profiling and real-time quantitative qRT-PCR analysis showed that AhLBD16, AhLBD33, AhLBD67, and AhLBD72 were candidate genes for salt stress, while AhLBD24, AhLBD33, AhLBD35, AhLBD52, AhLBD67, and AhLBD71 were candidate genes for drought stress. Our subcellular localization experiment revealed that AhLBD24, AhLBD33, AhLBD67, and AhLBD71 were located in the nucleus. Heterologous overexpression of AhLBD33 and AhLBD67 in Arabidopsis significantly enhanced tolerance to salt stress. Our results provide a theoretical basis and candidate genes for studying the molecular mechanism for abiotic stress in the peanut plant. Full article

Aluminum (Al³⁺) toxicity in acidic soils reduces root growth and can lead to a considerable reduction in peanut plants (Arachis hypogea L.). The caseinolytic protease (Clp) system plays the key role in abiotic stress response. However, it is still unknown whether it is involved in peanut response to Al³⁺ stress. The results from this study showed that Adenosine 5′-triphosphate (ATP)-dependent caseinolytic protease proteolytic subunit 6 (AhClpP6) in peanut plants was involved in the Al³ stress response through its effects on leaf photosynthesis. The AhClpP6 expression levels in the leaf and stem significantly increased with the Al³⁺ treatment times. Knockdown AhClpP6 peanut lines accumulated significantly more Al³⁺ when exposed to Al³⁺ stress, which reduced leaf photosynthesis. Furthermore, in response to Al³⁺ treatment, knockdown of AhClpP6 resulted in a flattened shape of chloroplasts, disordered and flattened thylakoid, and accumulating more starch grains than those of the wild-type (WT) peanut lines. Taken together, our results suggest that AhClpP6 regulates Al³⁺ tolerance by maintaining chloroplast integrity and enhancing photosynthesis. Full article

Casparian strip membrane domain proteins (CASPs), regulating the formation of Casparian strips in plants, serve crucial functions in facilitating plant growth, development, and resilience to abiotic stress. However, little research has focused on the characteristics and functions of AhCASPs in cultivated peanuts. In this study, the genome-wide identification and expression analysis of the AhCASPs gene family was performed using bioinformatics and transcriptome data. Results showed that a total of 80 AhCASPs members on 20 chromosomes were identified and divided into three subclusters, which mainly localized to the cell membrane. Ka/Ks analysis revealed that most of the genes underwent purifying selection. Analysis of cis elements suggested the possible involvement of AhCASPs in hormonal and stress responses, including GA, MeJA, IAA, ABA, drought, and low temperature. Moreover, 20 different miRNAs for 37 different AhCASPs genes were identified by the psRNATarget service. Likewise, transcriptional analysis revealed key AhCASPs responding to various stresses, hormonal processing, and tissue types, including 33 genes in low temperature and drought stress and 41 genes in tissue-specific expression. These results provide an important theoretical basis for the functions of AhCASPs in growth, development, and multiple stress resistance in cultivated peanuts. Full article

Peanut is a staple crop suitable for mechanized harvest and a source of plant proteins and fatty acids. It is widespread in Asia and North America, while there is limited cultivation in Europe despite potentially favorable climatic conditions. To test the adaptability of peanut in the Mediterranean area, a two-year field trial was carried out with one Spanish-type and one Virginia-type genotype cultivated under two water regimes (full irrigation and half irrigation supply). In order to test the response to fertilization management, three treatments were carried out, including an unfertilized control, a N-fertilized treatment, and a N-fertilized treatment inoculated with a commercial mixture of plant-growth promoting microorganisms, including two Bacillus species, Trichoderma and arbuscular mycorrhizal fungi (AMF). Microbiological soil analysis assessed the robustness of bacilli and their viability in soil. The Virginia-type genotype showed a better adaptability, with a positive response to irrigation and biofertilization. In particular, the inoculated treatment led to the highest agricultural crop water productivity, with important implications for sustainability. The impact of agronomic strategies was evaluated also in relation to storage proteins. The expression of 7s vicilin fraction showed a variability associated with water supply. Full article

Diseases contribute to attainment of less than 50% of the local groundnut potential yield in Kenya. This study aimed to evaluate the agronomic characteristics (flowering and germination), disease incidence, yield performance (biomass, harvest index, 100-pod, 100-seed, and total pod weight), and aflatoxin accumulation in six peanut varieties. A field experiment was conducted using four newly improved peanut varieties: CG9, CG7, CG12, and ICGV-SM 90704 (Nsinjiro), and two locally used varieties: Homabay local (control) and 12991, and in a randomized complete block design with three replications. The disease identification followed the International Crop Research Institute for the Semi-Arid Tropics (ICRISAT) rating scale and further isolation of fungal contaminants was conducted by a direct plating technique using potato dextrose agar. The aflatoxin levels in the peanuts were determined after harvesting using the ultrahigh performance liquid chromatography and fluorescence detection (UHPLC-FLD) technique. ICGV-SM 90704 showed the least average disease incidence of 1.31 ± 1.75%, (P < 0.05); the lowest total aflatoxin levels (1.82 ± 1.41 μg kg⁻¹) with a range 0.00–0.85 μg kg⁻¹ for total aflatoxins and a range 0.00–1.24 μg kg⁻¹ for Aflatoxin B₁. The locally used varieties (12991 and the control) revealed the highest disease incidence (5.41 ± 8.31% and 7.41 ± 1.88%), respectively. ICGV-SM 90704 was the best performing among all the six varieties with an average total pod weight (9.22 ± 1.19 kg), 100-pod weight (262.93 ± 10.8 g), and biomass of (27.21 ± 5.05 kg) per row. The 12991 variety and the control showed the least total pod weight (1.60 ± 0.28 and 1.50 ± 1.11 kg, respectively) (P = 0.0001). The newly improved varieties showed lower disease rates, low levels of aflatoxins, and higher yields than the locally used varieties. Full article

Enzymatic hydrolysis of lignocellulose materials has been identified as the rate-limiting step during anaerobic digestion. The application of pretreatment techniques can influence the biodegradability of lignocellulose substrate. This study combined Fe₃O₄ nanoparticles, which serve as a heterogeneous catalyst during anaerobic digestion, with different particle sizes of Arachis hypogea shells. Batch anaerobic digestion was set up at mesophilic temperature for 35 days. The results showed that 20 mg/L Fe₃O₄ additives, as a single pretreatment, significantly influence biogas and methane yields with an 80.59 and 106.66% increase, respectively. The combination of 20 mg/L Fe₃O₄ with a 6 mm particle size of Arachis hypogea shells produced the highest cumulative biogas yield of 130.85 mL/gVS_added and a cumulative methane yield of 100.86 mL/gVS_added. This study shows that 20 mg/L of Fe₃O₄ additive, combined with the particle size pretreatment, improved the biogas and methane yields of Arachis hypogea shells. This result can be replicated on the industrial scale to improve the energy recovery from Arachis hypogea shells. Full article

A two-year (2020–2021) field experiment was conducted to investigate the impact of particular nanoparticles and biofertilizers on the growth, yield, and biochemical attributes of peanuts (Cv. Giza 6). Before planting, the seeds were inoculated with two biofertilizers, mycorrhiza and phosphorine, and were considered the main plot. The subplot contained foliar sprays of nanoparticles, i.e., 200 ppm boron (B), 200 ppm calcium (Ca), their combination (Ca+B), and the control (no spray). The results revealed that mycorrhiza significantly increased 100-seed weight (70.45 g), seed yield (1.9 ton/ha), biological yield (7.5 ton/ha), crop growth rate (CGR) (2.9 g day⁻¹ m⁻²), branching number (12.5), and protein content (22.96) compared with the control or phosphorine. Among the nanoparticles, Ca+B maximally improved plant height, CGR, 100-seed weight, shelling percentage, seed yield, oil content, and seed protein, while plants treated with B exhibited maximum seed nitrogen, pods per plant, and biological yield compared to other treatments. Overall, plants treated with Ca and B nanoparticles and mycorrhiza exhibited remarkable improvement in their growth, yield, and biochemical attributes, suggesting that nanotechnology and biofertilization are steps toward environmentally friendly, progressive farming. This study laid the basis for further elucidation of the molecular mechanism of plants in response to these nanoparticles and biofertilizers. Full article

Intercropping improves land utilization with more crops grown together; however, shorter crops in intercropping experience stress, being shaded by the taller crops. Systematic changes in phenotype, physiology, yield, and gene regulation under shade stress in peanut are largely unknown, although shade responses have been well analyzed in model plants. We exposed peanut plants to simulated 40% and 80% shade for 15 and 30 days at the seedling stage, flowering stage, and both stages. Shade caused the increased elongation growth of the main stem, internode, and leaf, and elongation was positively associated with auxin levels. Shade stress reduced peanut yield. Further comparative RNA-seq analyses revealed expressional changes in many metabolism pathways and common core sets of expressional regulations in all shade treatments. Expressional downregulation of most genes for light-harvesting and photosynthesis agreed with the observed decreased parameters of photosynthesis processes. Other major regulations included expressional downregulation of most core genes in the sucrose and starch metabolism, and growth-promoting genes in plant hormone signal pathways. Together, the results advance our understanding of physiological and molecular regulation in shade avoidance in peanut, which could guide the breeding designing in the intercropping system. Full article