Search Results (22)

Production of a healthy crop of protein- and oil-rich soybean seeds requires a significant amount of nitrogen. Under ideal conditions, most of this nitrogen comes from the root nodules, where a symbiotic relationship with Bradyrhizobium japonicum fixes nitrogen from the atmosphere. Thus, growers generally think of soybeans as not needing nitrogen fertilization. However, a lack of B. japonicum or other unfavorable field conditions can produce inefficient nodulation, which leads to reduced vigor and yield under conditions of low soil nitrogen availability. Thus, additional resources for identifying nitrogen deficiency in soybean and strategies for the rescue application of nitrogen are needed. To generate a gradient of nitrogen deficiency, we applied different amounts of nitrogen (in the form of urea) to nodulation-deficient soybeans grown in sandy fields in South Carolina. Comparison of the ground truth data and aerial imagery suggest that leaf nitrogen deficiency can be effectively identified in the field based on plant height and color. Side dressing nitrogen fertilizer in the form of urea to nitrogen-deficient plots at the R1 stage was shown to rescue plant growth and increase crop yield. We conclude that identification and fertilization of patches of soybeans with low nitrogen content is a feasible strategy to increase soybean productivity. Although additional studies are needed to expand these results to other soil conditions, we recommend that nitrogen-deficient soybeans be treated with 40–50 pounds per acre (45–56 kg per hectare) of nitrogen at or before flowering to restore yield potential. Full article

Small noncoding RNAs are recognized as crucial regulators of seed germination, but their role in seed aging remains unclear. To address this, we performed RNA sequencing (RNA-seq) on barley (Hordeum vulgare L.) seeds with varying viability levels after long-term storage in hermetically sealed containers since the 1972 harvest. This globally unique material, characterized by genetic homogeneity and contrasting germination capacities, enabled an in-depth analysis of microtranscriptomic changes during germination. We identified 62 known miRNAs from 11 families and 234 novel miRNAs, with miR159, miR168, and miR166 showing consistently high expression across all germination stages and viability groups. Differential expression analysis revealed 28 miRNAs whose abundance varied significantly with seed viability and germination phase. Functional predictions supported by quantitative reverse transcription PCR (qRT–PCR) and degradome-based target identification indicated that these miRNAs regulate key developmental and metabolic pathways. Several isomiRs exhibited sample-specific expression, suggesting the viability-dependent activation of distinct molecular mechanisms. Gene Ontology analysis highlighted processes related to nucleic acid binding, nuclear organization, and cytoplasmic metabolism as central during germination. We propose that miRNA profiles may reflect an “epigenetic inheritance”—a molecular memory of aging stored in seeds—rather than solely a response to current conditions. This concept may help explain aging-related phenotypes such as delayed germination and reduced vigor, warranting further investigation. Full article

Plant extracellular vesicles are non-self-replicating particles released by living plant cells and delimited by a lipid bilayer. They contain a large amount of lipids, RNA, and proteins. Seed vigor plays an important role in agricultural production and preservation of germplasm resources. Extracellular vesicles with cross-species communication with bioactive molecules can resist pathogens, exhibit anti-aging properties, and perform other functions; however, its potential influence on seed vigor has not been reported. In this study, rice seeds with different germination percentages were used to extract extracellular vesicles, endogenous proteins, and RNA. Protein qualitative identification and miRNA differential analysis were performed to analyze the regulatory mechanism of extracellular vesicles on seed vigor. Results: The profiles of four miRNA families were found to be significantly different: osa-miR164, osa-miR168, osa-miR166, and osa-miR159. Protein correlation analysis predicted that extracellular vesicles might mediate the synthesis of the seed cell wall; glyoxic acid cycle and tricarboxylic acid cycle; non-specific lipid transfer; mitochondrial quality control; and other biological processes to regulate rice seed viability. In addition, cupin protein, phospholipase D, aldehyde dehydrogenase, seven heat shock proteins (especially BiP1 and BiP2), protein disulfide isomerase-like (PDI), thioredoxin, calnexin and calreticulin, glutathione transferase, and other proteins found in extracellular vesicles were closely related to seed vigor. This provides a novel direction for the study of the regulation mechanism of seed vigor. Full article

Seed coat cracking and green seeds threaten soybean crop production. Seed coat cracking results from a complex interplay of genetic factors, environmental stresses, and crop management practices. Green seeds, linked to water deficit, nutritional deficiencies, and environmental stresses, exhibit reduced quality and viability. The intricate relationships between seed coat integrity and seed permeability, influenced by the lignin content, porosity, and color, play a pivotal role in seed germination, storage potential, and resistance to field stresses. These issues reverberate through the soybean agricultural supply chain. Strategic interventions are crucial to address these abnormalities and ensure soybean productivity. Seed germination and vigor are reduced due to seed coat cracking and green seeds, undermining food security and necessitating additional resources for disease management. The occurrence and identification of green seeds and seeds with cracks in the seed coat were also reported by identifying the genes and QTLs (quantitative trait loci) associated with these characteristics. Herbicides, commonly used in weed management, may offer a strategic approach to mitigating seed coat cracking and green seed occurrence. Understanding the complex interactions between the genetics, environmental factors, and management practices influencing seed abnormalities is essential as global climate change intensifies. This review emphasizes the need for integrated strategies, balanced plant nutrition, and cohesive phytosanitary management to mainly alleviate seed coat cracking and greenish occurrences in soybeans and other plant species. Full article

Soybean (Glycine max) is an economically important cash crop and food source that serves as a key source of high-quality plant-derived protein and oil. Seed vigor is an important trait that influences the growth and development of soybean plants in an agricultural setting, underscoring a need for research focused on identifying seed vigor-related genetic loci and candidate genes. In this study, a population consisting of 207 chromosome segment substitution lines (CSSLs) derived from the crossing and continuous backcrossing of the Suinong14 (improved cultivar, recurrent parent) and ZYD00006 (wild soybean, donor parent) soybean varieties was leveraged to identify quantitative trait loci (QTLs) related to seed vigor. The candidate genes detected using this approach were then validated through RNA-seq, whole-genome resequencing, and qPCR approaches, while the relationship between specific haplotypes and seed vigor was evaluated through haplotype analyses of candidate genes. Phenotypic characterization revealed that the seed vigor of Suinong14 was superior to that of ZYD00006, and 20 total QTLs were identified using the selected CSSLs. Glyma.03G256700 was also established as a seed vigor-related gene that was upregulated in high-vigor seeds during germination, with haplotypes for this candidate gene also remaining consistent with observed soybean seed vigor. The QTLs identified herein can serve as a foundation for future marker-assisted and convergent breeding efforts aimed at improving seed vigor. In addition, future molecular and functional research focused on Glyma.03G256700 has the potential to elucidate the signaling network and key regulatory mechanisms that govern seed germination in soybean plants. Full article

This study was conducted to investigate the antagonistic potential of endophytic and rhizospheric bacterial isolates obtained from Citrullus colocynthis in suppressing Fusarium solani and Pythium aphanidermatum and promoting the growth of cucumber. Molecular identification of bacterial strains associated with C. colocynthis confirmed that these strains belong to the Achromobacter, Pantoea, Pseudomonas, Rhizobium, Sphingobacterium, Bacillus, Sinorhizobium, Staphylococcus, Cupriavidus, and Exiguobacterium genera. A dual culture assay showed that nine of the bacterial strains exhibited antifungal activity, four of which were effective against both pathogens. Strains B27 (Pantoea dispersa) and B28 (Exiguobacterium indicum) caused the highest percentage of inhibition towards F. solani (48.5% and 48.1%, respectively). P. aphanidermatum growth was impeded by the B21 (Bacillus cereus, 44.7%) and B28 (Exiguobacterium indicum, 51.1%) strains. Scanning electron microscopy showed that the strains caused abnormality in phytopathogens’ mycelia. All of the selected bacterial strains showed good IAA production (>500 ppm). A paper towel experiment demonstrated that these strains improved the seed germination, root/shoot growth, and vigor index of cucumber seedlings. Our findings suggest that the bacterial strains from C. colocynthis are suppressive to F. solani and P. aphanidermatum and can promote cucumber growth. This appears to be the first study to report the efficacy of these bacterial strains from C. colocynthis against F. solani and P. aphanidermatum. Full article

Seed aging, a common physiological phenomenon during forage seed storage, is a crucial factor contributing to a loss of vigor, resulting in delayed seed germination and seedling growth, as well as limiting the production of hay. Extensive bodies of research are dedicated to the study of seed aging, with a particular focus on the role of the production and accumulation of reactive oxygen species (ROS) and the ensuing oxidative damage during storage as a primary cause of decreases in seed vigor. To preserve optimal seed vigor, ROS levels must be regulated. The excessive accumulation of ROS can trigger programmed cell death (PCD), which causes the seed to lose vigor permanently. LESION SIMULATING DISEASE (LSD) is one of the proteins that regulate PCD, encodes a small C2C2 zinc finger protein, and plays a molecular function as a transcriptional regulator and scaffold protein. However, genome-wide analysis of LSD genes has not been performed for alfalfa (Medicago sativa), as one of the most important crop species, and, presently, the molecular regulation mechanism of seed aging is not clear enough. Numerous studies have also been unable to explain the essence of seed aging for LSD gene regulating PCD and affecting seed vigor. In this study, we obtained six MsLSD genes in total from the alfalfa (cultivar Zhongmu No. 1) genome. Phylogenetic analysis demonstrated that the MsLSD genes could be classified into three subgroups. In addition, six MsLSD genes were unevenly mapped on three chromosomes in alfalfa. Gene duplication analysis demonstrated that segmental duplication was the key driving force for the expansion of this gene family during evolution. Expression analysis of six MsLSD genes in various tissues and germinating seeds presented their different expressions. RT-qPCR analysis revealed that the expression of three MsLSD genes, including MsLSD2, MsLSD5, and MsLSD6, was significantly induced by seed aging treatment, suggesting that they might play an important role in maintaining seed vigor. Although this finding will provide valuable insights into unveiling the molecular mechanism involved in losing vigor and new strategies to improve alfalfa seed germinability, additional research must comprehensively elucidate the precise pathways through which the MsLSD genes regulate seed vigor. Full article

PEAR proteins are a type of plant-specific DNA binding with one finger (Dof) transcription factors that play a key role in the regulation of plant growth, especially during phloem cell growth and seed germination in Arabidopsis. However, the identification, characteristics and function of PEAR proteins, particularly in woody plants, need to be further studied. In the present study, 43 candidate PEAR proteins harboring the conserved Zf-Dof domain were obtained in Populus yunnanensis. Based on phylogenetic and structural analysis, 10 representative PEAR candidates were selected, belonging to different phylogenetic groups. The functions of PEAR proteins in the stress response, signal transduction, and growth regulation of stem cambium and roots undergoing vigorous cell division in Arabidopsis were revealed based on their expression patterns as characterized by qRT-PCR analysis, in accordance with the results of cis-element analysis. In vitro experiments showed that the interaction of transcription factor (E2F) and cyclin indirectly reflects the growth regulation function of PEAR through light signaling and cell-cycle regulation. Therefore, our results provide new insight into the identity of PEAR proteins and their function in stress resistance and vigorous cell division regulation of tissues in P. yunnanensis, which may serve as a basis for further investigation of the functions and characteristics of PEAR proteins in other plants. Full article

Doubled haploid (DH) technology has become integral to maize breeding programs to expedite inbred line development and increase the efficiency of breeding operations. Unlike many other plant species that use in vitro methods, DH production in maize uses a relatively simple and efficient in vivo haploid induction method. However, it takes two complete crop cycles for DH line generation, one for haploid induction and the other one for chromosome doubling and seed production. Rescuing in vivo induced haploid embryos has the potential to reduce the time for DH line development and improve the efficiency of DH line production. However, the identification of a few haploid embryos (~10%) resulting from an induction cross from the rest of the diploid embryos is a challenge. In this study, we demonstrated that an anthocyanin marker, namely R1-nj, which is integrated into most haploid inducers, can aid in distinguishing haploid and diploid embryos. Further, we tested conditions that enhance R1-nj anthocyanin marker expression in embryos and found that light and sucrose enhance anthocyanin expression, while phosphorous deprivation in the media had no affect. Validating the use of the R1-nj marker for haploid and diploid embryo identification using a gold standard classification based on visual differences among haploids and diploids for characteristics such as seedling vigor, erectness of leaves, tassel fertility, etc., indicated that the R1-nj marker could lead to significantly high false positives, necessitating the use of additional markers for increased accuracy and reliability of haploid embryo identification. Full article

Sucrose phosphate synthase (SPS), a crucial rate-limiting enzyme that catalyzes the synthesis of precursors of sucrose, plays an indispensable role in the regulation of seed potato vigor. Nonetheless, the genes that encode SPS in potato have not undergone complete analysis, and the primary genes responsible for the regulation of seed potato vigor have not been screened and identified. In this study, four StSPS family members were identified by comparing the potato genome database with homologous proteins. Using bioinformatics, the physicochemical properties, subcellular localization, sequence structure, conserved motifs, and phylogenetics of StSPS were analyzed. The expression levels of StSPS in different potato tissues, from dormancy to sprouting in the seed potato tubers, were measured via qRT-PCR. The expression data from the potato genome database and previous transcriptome and proteome studies of dormancy to sprouting were also compared. After combining the analysis of SPS enzyme activity in diverse tuber tissues and the correlation analysis between multiple varieties with different dormancy periods and the expression of StSPS1, the primary gene StSPS1 that might regulate seed potato vigor was identified. This study set a theoretical and experimental groundwork for further verification and clarification of the regulatory function of StSPS1 in alterations in seed potato vigor. Full article

Presoaking seeds in water (hydropriming) or in a solution, usually of polyethylene glycol (PEG) or various salts at low water potential (osmopriming), has been demonstrated to improve the germination of seeds of numerous species including vegetables (carrot, celery, leek, lettuce, tomato), floral plants (cyclamen, primrose, pansy) and others (sugar beet, rape, soybean, sunflower). This treatment allows the germination stricto sensu to occur but prevents the radicle protrusion. Germination of primed seeds is more rapid and uniform than that of unprimed ones. Primed seeds germinate in a wider range of temperatures and are less sensitive to oxygen deprivation. Interestingly, priming also improves the germination of aged seeds. The stimulatory effect of priming persists after redrying and often during storage; however, primed seeds often deteriorate faster during storage or accelerated aging than unprimed ones. A better understanding of the mechanisms involved during priming allows us to suggest markers of the effectiveness of priming. Among these markers, ethylene production during imbibition, cell-cycle processes (DNA replication, ß-tubulin), soluble sugar metabolism (raffinose family oligosaccharides, in particular), reactive oxygen species scavenging through antioxidant systems and energy metabolism are correlated to seed vigor. Global approaches (proteomic, metabolomic or transcriptomic) could also result in the identification of new markers. Full article

Seed-borne fungi are solemn and deleterious pathogens capable of causing significant losses of quantity and quality losses in maize seeds and seedlings. They infect the crop at all points of the production chain from farms to stores. A yield loss of up to 50% can be encountered. Currently, chemical control of the disease is being implemented, though it is accompanied by several negative effects. This study aimed at identifying seed-borne fungi of maize and effective management options. A deep-freezing blotter method and morphological identification of the fungal species were implemented. The seed-borne fungi detected were Fusarium verticillioides, Aspergillus flavus, Aspergillus niger, Penicillium spp., Rhizopus spp., and Curvularia spp. However, in farmer-saved seeds, fungal incidences were significantly higher (p < 0.01) than in certified seeds. To identify more effective management options, the efficacy of water and ethanol-extracted bio-fungicides from three plant species, namely, neem (Azadirachta indica), ginger (Zingiber officinale), and coffee (Coffea arabica) were evaluated. From in vitro assays, ethanol-extracted bio-fungicides have a 100% inhibitory effect on fungal growth, whilst the inhibitory effects of water-extracted bio-fungicides are 55.88% (Azadirachta indica) and 46.31% (Zingiber officinale), followed by 5.15% (Coffea arabica). For the case of an in vivo assay, maize seeds treated with water-extracted bio-fungicides have higher seed germination and seedling vigor percentages. For germination, seeds treated with water-extracted bio-fungicides have higher percentages (neem and ginger (90%) followed by coffee (72.5%)) than ethanol-extracted bio-fungicides (neem (0%), ginger (2.5%), and coffee (0%)). A similar observation is made for seedling weight. Therefore, the tested water-extracted bio-fungicides can be used in treating seeds before sowing them. Further studies on effective methods of extracting bioactive compounds, and improving their shelf life, are recommended. Full article

Drought stress influences the vigor of plant seeds and inhibits seed germination, making it one of the primary environmental factors adversely affecting food security. The seed germination stage is critical to ensuring the growth and productivity of soybeans in soils prone to drought conditions. We here examined the genetic diversity and drought-tolerance phenotypes of 410 accessions of a germplasm diversity panel for soybean and conducted quantitative genetics analyses to identify loci associated with drought tolerance of seed germination. We uncovered significant differences among the diverse genotypes for four growth indices and five drought-tolerance indices, which revealed abundant variation among genotypes, upon drought stress, and for genotype × treatment effects. We also used 158,327 SNP markers and performed GWAS for the drought-related traits. Our data met the conditions (PCA + K) for using a mixed linear model in TASSEL, and we thus identified 26 SNPs associated with drought tolerance indices for germination stage distributed across 10 chromosomes. Nine SNP sites, including, for example, Gm20_34956219 and Gm20_36902659, were associated with two or more phenotypic indices, and there were nine SNP markers located in or adjacent to (within 500 kb) previously reported drought tolerance QTLs. These SNPs led to our identification of 41 candidate genes related to drought tolerance in the germination stage. The results of our study contribute to a deeper understanding of the genetic mechanisms underlying drought tolerance in soybeans at the germination stage, thereby providing a molecular basis for identifying useful soybean germplasm for breeding new drought-tolerant varieties. Full article

Seed vigor and seed germination are very important traits, determined by several factors including genetic and physical purity, mechanical damage, and physiological condition, characterized by maintaining a high seed vigor and stable content after storage. The search for molecular markers related to improvement in seed vigor under adverse condition is an important issue in maize breeding currently. Higher sowing quality of seeds is necessary for the development of the agriculture production and better ability to resist all kinds of adversity in the seeds’ storage. Condition is a very important factor affecting the yield of plants, thanks to the construction of their vitality. Identification of molecular markers associated with seed germination and seed vigor may prove to be very important in the selection of high-yielding maize varieties. The aim of this study was to identify and select new markers for maize (SNP and SilicoDArT) linked to genes influencing the seed germination and seed vigor in inbred lines of maize (Zea mays L.). The plant material used for the research was 152 inbred maize lines. The seed germination and seed vigor were analyzed. For identification of SNP and SilicoDArT markers related to the seed germination and seed vigor, the SilicoDarT technique developed by Diversity Arrays Technology was used. The analysis of variance indicated a statistically significant differentiation between genotypes for both observed traits. Positive (r = 0.41) correlation (p < 0.001) between seed germination and seed vigor was observed. As a result of next-generation sequencing, the molecular markers SilicoDArT (53,031) and SNP (28,571) were obtained. Out of 81,602 identified SilicoDArT and SNP markers, 15,409 (1559 SilicoDArT and 13,850 SNP) were selected as a result of association mapping, which showed them to be significantly related to the analyzed traits. The 890 molecular markers were associated with seed vigor, and 1323 with seed germination. Fifty-six markers (47 SilicoDArT and nine SNP) were significant for both traits. Of these 56 markers, the 20 most significant were selected (five of these markers were significant at the level of 0.001 for seed vigor and at the level of 0.05 for seed germination, another five markers were significant at the level of 0.001 for seed germination and at the level of 0.05 for seed vigor, five markers significant at the level of 0.001 only for seed vigor and five significant at the level of 0.001 only for seed germination also selected). These markers were used for physical mapping to determine their location on the genetic map. Finally, it was found that six of these markers (five silicoDArT—2,435,784, 4,772,587, 4,776,334, 2,507,310, 25,981,291, and one SNP—2,386,217) are located inside genes, the action of which may affect both seed germination and seed vigor. These markers can be used to select genotypes with high vigor and good seed germination. Full article

The identification of seed vigor is of great significance to improve the seed germination rate, increase crop yield, and ensure product quality. In this study, based on a hyperspectral data acquisition system and an improved feature extraction algorithm, an identification model of the germination characteristics for corn seeds was constructed. In this research, hyperspectral data acquisition and the standard corn seed germination test for Zhengdan 958 were carried out. By integrating the hyperspectral data in the spectral range of 386.7–1016.7 nm and the first derivative information of the spectral data, the root length prediction for corn seeds was successfully completed. The data regression model and prediction relationship between the spectral characteristics and seedling root length were established by principal component regression, partial least squares, and support vector regression. The first derivative information of the hyperspectral data was obtained by comparing the prediction model results with the original spectral data, which was preprocessed by Savitzky–Golay smoothing, multiplicative scatter correction, standard normal variate, and curve fitting. The results showed that the prediction model based on the first-order differential spectral data showed better performance than the one based on the spectral data obtained by other processing algorithms. By comparing the prediction results using different data characteristics and regression models, it was found that the hyperspectral method can effectively predict the root length of the seed, with the coefficient of determination reaching 0.8319. Full article