Soybean Genotypes Research Articles

Identification of Best General and Specific Combiners for Soybean Improvement

The present study on general combining ability effects and specific combining ability effects involves 15 parents viz., lines RKS 18, RKS 113, AUKS 199, AUKS 200, AUKS 212, RVSM 2011-35, JS 20-98, AUKS 202, AUKS 208, AUKS 218, JS 21-72, NRC 165 and tester JS 20-34, NRC 138, SL 958 with their 36 F1 hybrid through Line x Tester mating system. The present investigation was undertaken using Randomized Block Design with three replications. The combining ability effects were estimated for thirteen characters viz., days to 50% flowering, days to maturity, plant height, number of branches per plant, number of pods per plant, pod length, number of seeds per pod, 100-Seed weight, seed yield per plant, biological yield per plant, harvest index, protein content and oil content. The result showed that gca effects of parents and sca effects of hybrids were significant differed. Among the parents, AUKS 212 was found to be good general combiner based on the per se performance and gca effects for seed yield and other contributing traits and four hybrids AUKS 113 x SL 958, RVSM 2011-35 x NRC 138, AUKS 199 x JS 20-34 and NRC 165 x JS 20-34 were superior high sca effects for seed yield and yield contributing traits. These crosses can be utilized in future breeding programmes and exploitation of better segregants through pedigree method or single seed descent method in advance generations for improvement of yield and yield attributes coupled with quality traits sound soybean genotypes.

Genetic Analysis of Yield, Protein, and Oil Traits in Soybean Diallel Crosses for Enhanced Crop Quality and Productivity

The study was conducted at Sakha Research Station, ARC, Egypt, during three successive seasons from 2021 to 2023. A half diallel cross of fifteen F1 and F2 generations in addition to the six soybean parental genotypes namely, Japanese 13, Giza 111, Crawford, H18L54, Nc92-2231 and Linford were evaluated to determine the genetic behavior of yield and its components traits in both F1 and F2 generations, as well as seed protein and oil contents in F1. Results indicated that mean squares of General Combining Ability (GCA) and Specific Combining Ability (SCA) were significant and highly significant for all the studied characters of soybean genotypes in F1’s and F2’s, except SCA for 100-seed weight in F2’s only. The GCA/SCA ratios were less than unity in all traits, indicating that, the non-additive gene effects seemed to be responsible for the inheritance of these traits. The parental genotypes; H18L54, Nc 92-2231 and Linford seemed to be excellent combiners for days to flowering and maturity; however, Giza 111 and Japanese 13 were good combiners for seed yield. Meanwhile, Giza 111 was a good combiner for protein and oil content; also, H18L54 and Nc 92-2231 were good combiners for protein content. The crosses C7, C9, C10, C11 and C13 were earlier for maturity date, and also showed the most negative significant desirable Ŝij effects. The best (Ŝij) values in F2 were shown in the C1, C5, C8 and C15 crosses for seed yield/plant, these crosses also had the highest seed yield values in F2. The crosses; C5 and C8 showed significant to highly significant positive heterotic effects relative to the better parent for protein% and seed yield per plant. In addition three crosses; C13, C14, and C15 had highly significant positive heterotic effects relative to the better parent for oil % and seed yield per plant.

Stomatal Density Variation Within and Among Different Soybean Cultivars Across Various Growth Stages

Stomata regulate CO2 and water vapor exchange between leaves and the atmosphere, serving as a vital indicator of climate change resilience. Therefore, understanding the difference in stomatal numbers and patterns among different soybean cultivars across growth stages is essential to comprehending the complex mechanisms underlying soybean adaptation to climate change. The accurate measurements of stomatal density in soybean leaves are essential to understanding the complexity of stomatal density by environmental conditions. We demonstrated that the five epidermal sections and five microscopic images taken from both sides of each epidermal section at each leaf position (tip, middle, and bottom) were sufficient for stomatal measurements. Furthermore, we investigated variations in stomatal density among leaflet locations (left, right, and central) and leaf position across different growth stages. Notably, while there was no significant variation between the two leaves of the vegetative cotyledon (VC) stage and among the three leaflets of the V1 (first trifoliate) to V4 (fourth trifoliate) growth stages, leaves of the VC stage exhibited the lowest stomatal density, whereas those of the V4 stage exhibited the highest stomatal density. These findings could serve as a valuable tool for evaluating stomatal density, analyzing physiological differences under adverse climatic conditions, and phenotyping a large-scale population to identify the genetic factors responsible for stomatal density variations in soybean genotypes.

Characterisation of the Phenotypic Reaction of Brazilian Soybean Genotypes to Sclerotinia sclerotiorum Under Controlled Conditions

ABSTRACTWhite mould is a disease caused by the fungus Sclerotinia sclerotiorum, and it is considered one of the most devastating diseases in soybean crops, causing huge losses in productivity. In this study, we aimed to contribute to the genetic control of this disease by characterising the phenotypic reaction of 67 Brazilian soybean genotypes to S. sclerotiorum under controlled conditions. Plants were artificially inoculated with mycelium discs when they reached the four‐node phenological stage. Symptoms of white mould developed in all soybean genotypes. The resistance reaction was characterised by measuring the length of lesions on the main stem at 7 days after inoculation. Of the 67 genotypes evaluated, nine showed greater resistance to S. sclerotiorum, including 17S‐01443‐L8, 16S‐00630‐L4, GER_00003, 13S‐00001‐L2/FPS 2457 RR, BMX Torque I2X, P95Y02 IPRO, 17S‐00842‐L5, HO Pirapó IPRO and TMG 2359 IPRO. Twenty‐three genotypes showed an intermediate response, while 35 genotypes showed greater susceptibility to S. sclerotiorum. Further studies should be conducted under field conditions with the soybean genotypes that showed greater resistance response to S. sclerotiorum under controlled conditions.

A Novel Solid Media-Free In-Planta Soybean (Glycine max. (L) Merr.) Transformation Approach

Soybean’s lengthy protocols for transgenic plant production are a bottleneck in the transgenic breeding of this crop. Explants cultured on a medium for an extended duration exhibit unanticipated modifications. Stress-induced somaclonal variations and in vitro contaminations also cause substantial losses of transgenic plants. This effect could potentially be mitigated by direct shoot regeneration without solid media or in-planta transformation. The current study focused primarily on developing a rapid and effective media-free in-planta transformation technique for three soybean genotypes (Wm82) and our newly developed two hybrids, designated as ZX-16 and ZX-3. The whole procedure for a transgenic plant takes the same time as a stable grown seedling. Multiple axillary shoots were regenerated on stable-grown soybean seedlings without the ectopic expression of developmental regulatory genes. An approximate amount of 200 µL medium with a growth regulator was employed for shoot organogenesis and growth. The maximal shoot regeneration percentages in the Wm82 and ZX-3 genotypes were 87.1% and 84.5%, respectively. The stable transformation ranged from 3% to 8.0%, with an average of 5.5%. This approach seems to be the opposite of the hairy root transformation method, which allowed transgenic shoots to be regenerated on normal roots. Further improvement regarding an increase in the transformation efficiency and of this technique for a broad range of soybean genotypes and other dicot species would be extremely beneficial in achieving increased stable transformation.

Morpho-physiological traits and stress indices reveal divergence in early-stage salt stress response in elite soybean germplasm

This study assessed the salt stress response of seventy soybean genotypes by exposing seedlings to sodium chloride (NaCl) concentrations of 0, 75, 100, and 125 mM. Salinity stress significantly reduced root length, shoot length, fresh and dry root/shoot weight, and root/shoot ratio. A total of 62 genotypes germinated at 125 mM, showing significant phenotypic variation in traits such as root length, shoot length, fresh shoot weight, and dry shoot weight. Pearson’s correlation analysis revealed a strong positive correlation between most morpho-physiological traits, suggesting their interdependence. Eight salinity tolerance indices i.e., Fresh Weight Stress Tolerance Index (FWSI), Dry Weight Stress Tolerance Index (DWSI), Root Length Salinity Index (RLSI), Shoot Length Salinity Index (SLSI), Salinity Tolerance Index (STI), Salinity Susceptibility Index (SSI), Tolerance Index (TI), and Percent Reduction (PR) were calculated to assess genotypes response. Na+ concentration and antioxidant activities significantly increased under salt stress compared to the control. The activities of antioxidant enzymes, as well as the levels of reactive oxygen species (ROS) such as H2O2 and O2−, were markedly higher under salt stress compared to the control. Hierarchical cluster analysis grouped genotypes into six clusters, with clusters V and VI comprising genotypes exhibiting higher salt tolerance based on high FWSI, DWSI, and STI values, and low PR, SSI, and TI values. Eight salinity tolerance indices, including Fresh Weight Stress Tolerance Index (FWSI), Dry Weight Stress Tolerance Index (DWSI), Root Length Salinity Index (RLSI), and Salinity Tolerance Index (STI), were used to evaluate the genotypes’ responses. The study revealed that the average FWSI value for all genotypes under treatments was 54.20 ± 12.93. The highest FWSI was recorded for the genotype Black (92.52), followed by NIBGE-224 (84.70) and NIBGE-183 (81.05). In contrast, Malakand-96 had the lowest FWSI (28.49), followed by SPS-10 (32.74) and SPS-08 (34.55). PGRA-91 had the highest STI (0.83), followed by SPS-9 (0.75) and NIBGE-115 (0.72), while NIBGE-335, SPS-24, and Malakand-96 had the lowest STI values. Positive correlations were observed between root length and shoot length (0.69**), shoot length and fresh shoot weight (0.63**), and other related traits. Overall, this study identified promising soybean genotypes with varying degrees of salt tolerance. These findings can be utilized in breeding programs to develop salt-tolerant soybean varieties for salinity-affected agricultural lands.

Genetic Diversity and Population Structure Analysis of Soybean [Glycine max (L.) Merrill] Genotypes Using Agro-Morphological Traits and SNP Markers

Background/Objectives: Understanding the genetic diversity of soybean genotypes can provide valuable information that guides parental selection and the design of an effective hybridization strategy in a soybean breeding program. In order to identify genetically diverse, complementary, and prospective parental lines for breeding, this study set out to ascertain the genetic diversity, relationships, and population structure among 35 soybean genotypes based on agro-morphological traits and Single Nucleotide Polymorphic (SNP) marker data. Methods/Results: Cluster analysis, based on agro-morphological traits, grouped the studied genotypes into four clusters. The first two principal components accounted for 62.8% of the total phenotypic variation, where days to 50% flowering, days to 95% maturity, grain yield, shattering score, and lodging score had high and positive contributions to the total variation. Using the SNP marker information, mean values of 0.16, 0.19, 0.067, and 0.227 were obtained for minor allele frequency (MAF), polymorphic information content (PIC), observed heterozygosity (Ho), and expected heterozygosity (He), respectively. Using different clustering approaches (admixture population structure, principal component scatter plot, and hierarchical clustering), the studied genotypes were grouped into four major clusters. Conclusions:The agro-morphological and molecular analysis results indicated the existence of moderate genetic diversity among the studied genotypes. The traits identified to be significantly related to yield provide valuable information for the genetic improvement of soybeans for yield.

Morphological Characterization-based Optimal Trait Selection for Improving Yield and Stability of Soybean (Glycine max L. Merrill)

The present investigation was convened during kharif, 2022 (July–October), rabi-Summer 2023 (January–May) and kharif, 2023 (July–October) at J.N.K.V.V., Jabalpur, Madhya Pradesh, India to characterize 165 diverse soybean germplasm lines in pursuance of DUS (Distinctness, Uniformity, and Stability) guidelines focusing on integrating optimal morphological traits to pre-fine soybean crop improvement. The study revealed significant variation among soybean genotypes. The hypocotyl color, controlled by a monogenic trait, was found in 77 genotypes, closely associated with violet flower color, whereas non-pigmented hypocotyls present in 88 genotypes were linked to white flowers. Growth habits were categorized as determinate (59), semi-determinate (103), and indeterminate (3), demonstrating that semi-determinate genotypes offer balanced resource allocation and reduced lodging. Most genotypes displayed medium flowering time (159) and medium plant height (134). Leaf shape was predominantly pointed ovate (121), with lanceolate leaves associated with higher number of seeds-1 pod. The presence of dark green leaves in 108 genotypes indicated higher chlorophyll content and enhanced photosynthetic efficiency to strengthen plant type. Semi-erect growth habit was prevalent in 152 genotypes, providing better soil coverage and moisture retention, while 13 genotypes showed erect growth. Pod pubescence was observed in 106 genotypes, offering protection against pests. These traits are found stable across the environment and may be used as an identification key for different varieties and donor germplasm lines.

Impact of flooding at the early reproductive growth stage on soybean yield and seed composition

AbstractFlooding stress is a growing threat to global soybean [Glycine max (L.) Merr.] production as the frequency and intensity of extreme precipitations are increasing due to climate change. Soybean is highly sensitive to flooding and substantial yield losses are observed due to a cascade of negative physiological responses induced by hypoxia. Hence, there is a pressing need for the development of flood‐tolerant genotypes. This study evaluated the grain yield and seed protein and oil content of 31 soybean genotypes over 2 years under both non‐flooding and flooding conditions, where flooding entailed a 4‐day partial water submergence during the early reproductive growth stages R1/R2. Mixed‐effects linear models were utilized to assess the impact of flood damage scores (FDSs, 1–4 scale) on observed phenotypes, as well as differences in observed phenotypes between tolerant, moderate, and susceptible genotypes across flooding and non‐flooding treatments. No significant impact of FDS was observed for seed protein and oil content. In addition, no significant differences in these phenotypes were observed between flooding and non‐flooding treatments across the various genotype categories. On average, for each unit increase in FDS, grain yield decreased by 432.7 kg ha−1 (17.4%). Tolerant genotypes experienced roughly 33% yield losses between flooding and non‐flooding treatments, while moderate and susceptible genotypes experienced 44% and 51% yield losses, respectively. The advancements in genomics and phenomics are promising for the identification and incorporation of novel flood‐tolerant alleles through plant breeding, potentially mitigating flooding‐induced yield losses across diverse environmental conditions.

The effect of sowing dates on the yield of soybean (Glycine max (L.) Merr.) accessions differing in maturity schedules under the climate conditions of Irkutsk Province

Background. Soybean is the main supplier of complete vegetable protein and oil. Prior to the emergence of new early-ripening cultivars, this crop was not cultivated in Irkutsk Province. Its introduction into the area requires a detailed study of agricultural practices, primarily the choice of optimal sowing dates. Materials and methods. Soybean cv. ‘Barguzin’, late-ripening under the conditions of Irkutsk Province, and early-ripening accession 15 served as the research objects. Field studies were carried out in 2019–2021. There were four sowing dates, from the first ten-day period of May through the first ten-day period of June. Results and conclusion. Cv. ‘Barguzin’ appeared highly productive under the climate of Irkutsk Province (its average seed yield in 2019–2021 was 2.7 t/ha), but its productivity was significantly influenced by weather conditions and sowing dates (seed yields varied from 1.4 to 3.6 t/ha). The optimal sowing times for this cultivar are the first and second ten-day periods of May. Early-ripening accession 15 was characterized by more stable yield values in the studied years (average productivity was 2.4 t/ha, minimum 1.9 t/ha, and maximum 3.2 t/ha). The preferred sowing times for this accession are the second and third ten-day periods of May. The case study of two soybean genotypes differing in maturation schedules revealed the need for individual selection of sowing dates. It was shown that the early-ripening soybean genotype imposed less stringent requirements on the choice of sowing dates.

High-protein soybean lines with stable seed protein content under heat and drought stresses

A significant factor determining the value of soybean is protein content, in addition to its importance as an oilseed. Increasing the seed protein content in soybean will make it a more valuable food and feedstock and enhance its importance in the international market. Due to this reason, developing high-protein soybean varieties is gaining increased industrial interest. To ensure profitable production, the stability of the high-protein trait needs to be verified under environmental stresses. The objectives of this study were to test whether the high-protein soybean genotypes can maintain their high seed protein content under heat and drought stresses imposed during seed filling and to assess the changes in their oil composition under stress conditions. The changes in seed protein and oil contents and oil composition of the high-protein lines NLM09–77, N14-7017, and N16-9924 under heat and drought stresses were assessed and compared against those of a recently released high-yielding, high-protein variety Benning HP; elite cultivars NC-Dunphy, NC-Raleigh, and NC-Dilday; low-protein breeding lines N11–9228 and N09-2505; heat-tolerant line DS25-1; and heat-susceptible line DT97-4290. We found that the high-protein genotypes NLM09–77, N16–9924, N14-7017, and Benning HP maintained their high seed protein contents under heat and drought stresses (46–55 %). Among them, NLM09–77 and N14-7017 were unique with no apparent negative relationship between the seed protein and oil contents. In terms of oil composition, N14-7017, NLM09-77, and Benning HP were similar to the elite cultivars NC-Dunphy and NC-Dilday. Additionally, the high-protein genotypes N14-7017, NLM09-77, and Benning HP did not exhibit any yield drag (2993–3150 kg ha−1vs 3289–3368 kg ha−1 for the elite cultivars). Taken together, our study demonstrates the usefulness of the advanced breeding lines NLM09–77 and N14-7017 and cultivar Benning HP for developing new varieties with enhanced nutritional value under climate change-associated stresses.

Assessment of genetic diversity by phenological traits, field performance, and Start Codon Targeted (SCoT) polymorphism marker of seventeen soybean genotypes (Glycine max L.).

The Egyptian-farmed soybeans have a wide range of genetic diversity which is most important in plant improvement programs in order to develop new higher yielding soybean genotypes. The present study is designed to determine the genetic variability among seventeen genotypes of cultivated soybean (Glycine max L.) by examining the phenotypic level at the seedling stage, field performance over two years 2022/2023 and genetically using Start Codon Targeted (SCoT) markers. Results indicated that the SCoT markers, 100 seed weight, and tip angle (TA) traits were positively correlated with H2L12, DR 101, H15L5, and H117 genotypes. In addition, the number of branches per plant and plant height were associated with H113, H32, Crowford, H129, and D7512035. Furthermore, the length of the first internode (LFI), root width (RW), root length (RL), and shoot length (SL) were more associated with Giza 111, NC105, and Hutcheson. The hierarchical cluster analysis (HCA) and its associated heatmap explored the differences among the genotypes. It showed that all examined parameters were clustered into four distinct clusters. The obtained results showed that genotypes NC105, H30, D75_12035, and H2L12 have promising phenological and morphological traits besides tracking the inheritance of nearby genes surrounding the ATG translation start codon since they are in a monoclades. The obtained results will help the breeder plan appropriate selection strategies for improving seed yield in soybeans through hybridization from divergent clusters.

Morphological Assessment of Drought Stress Tolerant Soybean Genotypes in Bangladesh

Soybean (Glycine max (L.) Merr) is the most important commercial grain legume and oil seed crop which represents the most important plant source of vegetable oil and protein in the world. The water stress tolerance of the fifty soybean genotypes was evaluated in a glasshouse at the Bangladesh Institute of Nuclear Agriculture (BINA). The study was carried out to identify the drought tolerant soybean genotype(s) for improving yield under rainfed conditions in Bangladesh. Drought stress was induced by withholding water completely from 21 days after emergence. The water stress was continued until wilting symptom persisted on plant overnight. Water stress caused an overall reduction in some morphological and yield contributing characters such as plant hight, number of branches plant-1, internode length, pod plant-1, seeds pod-1, hundred (100) seeds weight and finally the seed yield of soybean. The studied genotypes were categorized into four groups based on their yield reduction under drought stress conditions. Five genotypes YESOY-4, PK-416, Shohag, SBM-09 and Binasoybean-6 were categorized as tolerant (<35% yield reduction), fourteen genotypes were categorized as moderately tolerant (35%-60% yield reduction), twenty five genotypes were categorized as moderately susceptible (61%-80% yield reduction) and rest six genotypes were categorized as susceptible (>80% yield reduction). These five genotypes YESOY-4, PK-416, Shohag, SBM-09 and Binasoybean-6 study further for developing drought tolerant soybean verities which may be helpful for quality oil seed production.

Evaluation of Early Maturing Soya Bean (Glycine max.) Genotypes for Pod Shattering Resistance and High Yielder at Western Tigray, Ethiopia

Pod shattering is occurring after the pods reached maturity which can cause considerable yield loss in soya bean crop. The aims of this study were to evaluate the pod shattering resistance and the performance of the agronomic traits of several soybean genotypes. Field experiment was conducted at Humera district during 2018 cropping season using sixteen soya bean genotypes. Treatments were evaluated with RCBD and replicated three times. Pod shattering, number of branches, seed per pod, pod per plant, hundred seed weight and seed yield was shows a significant (P<0.01) variation among genotypes. While; there was not a significant variation among genotypes in terms of the number of days from planting to flowering and maturity. The mean pod shattering was ranged from scale1.25 to 4. Maximum amount of pod shattering was measured in the genotypes PI423959 (4), PI506764 (3.75) and PI417085 (3.25). However, minimum amount of pod shattering was measured in the genotypes of PI417116 (1.25), Desha (1.75) and PI417132 (2). Highest yield was obtained from the genotypes PI714116 (19.29kg/ha) and PI417132 (16.54kg/ha). However, lowest yield was obtained from the genotypes Williams (check) (6.7kg/ha) followed by PI223963 (8.53 kg/ha) and Nova (check) (9.86 kg/ha).

Differential Drought Responses of Soybean Genotypes in Relation to Photosynthesis and Growth-Yield Attributes.

Water scarcity leads to significant ecological challenges for global farming production. Sustainable agriculture depends on developing strategies to overcome the impacts of drought on important crops, including soybean. In this present study, seven promising soybean genotypes were evaluated for their drought tolerance potential by exposing them to water deficit conditions. The control group was maintained at 100% field capacity (FC), while the drought-treated group was maintained at 50% FC on a volume/weight basis. This treatment was applied at the second trifoliate leaf stage and continued until maturity. Our results demonstrated that water shortage exerted negative impacts on soybean phenotypic traits, physiological and biochemical mechanisms, and yield output in comparison with normal conditions. Our results showed that genotype G00001 exhibited the highest leaf area plant-1 (483.70 cm2), photosynthetic attributes like stomatal conductance (gs) (0.15 mol H2O m-2 s-1) and photosynthetic rate (Pn) (13.73 μmol CO2 m-2 s-1), and xylem exudation rate (0.25 g h-1) under drought conditions. The G00001 genotype showed greater leaf greenness by preserving photosynthetic pigments (total chlorophylls (Chls) and carotenoids; 4.23 and 7.34 mg g-1 FW, respectively) in response to drought conditions. Soybean plants accumulated high levels of stress indicators like proline and malondialdehyde when subjected to drought stress. However, genotype G00001 displayed lower levels of proline (4.49 μg g-1 FW) and malondialdehyde (3.70 μmol g-1 FW), indicating that this genotype suffered from less oxidative stress induced by drought stress compared to the other investigated soybean genotypes. Eventually, the G00001 genotype had a greater yield in terms of seeds pod-1 (SP) (1.90) and 100-seed weight (HSW) (14.60 g) under drought conditions. On the other hand, BD2333 exhibited the largest decrease in plant height (37.10%), pod number plant-1 (85.90%), SP (56.20%), HSW (54.20%), gs (90.50%), Pn (71.00%), transpiration rate (59.40%), relative water content (34.40%), Chl a (79.50%), total Chls (72.70%), and carotenoids (56.70%), along with the maximum increase in water saturation deficit (290.40%) and malondialdehyde content (280.30%) under drought compared to control conditions, indicating its higher sensitivity to drought stress. Our findings suggest that G00001 is a promising candidate to consider for field trials and further evaluation of its molecular signature may help breeding other elite cultivars to develop drought-tolerant, high-yielding soybean varieties.

Evaluation of Agronomic Performance and Resistance to Cercospora (Cercospora sojina) Leaf Spot of Selected Soya bean Genotypes in Western Tigray, Ethiopia

Aim of the current study was to evaluate soya bean genotypes for yield and yield traits and cercospora (Cercosporasojina) leaf spot disease under field condition. Field experiment was conducted at Humera district during 2018 cropping season using 16soya bean genotypes. Treatments were evaluated with RCBD and replicated three times. Number of days from planting to days of flowering and days of maturity, number of pod per plant, pod shattering, seed yield and cercospora leaf spot disease were showed a significant (P<0.01) variation among genotypes. All varieties were moderately resistance to pod shattering except PN13-1 (3.1) was moderately susceptible and Parc-3, Parc-5 and PN13-10were resistance. Highest yields were recorded from genotypes PN13-2 at 20.32q/ha and PN13-9 at 19.77q/ha. On the other hand, the lowest yields were recorded from genotypes PN13-3 at 7.49q/ha and PN13-1 at 9.95q/ha. Genotypes PN13-2 and PN13-7 have been identified as displaying resistance to Cercospora leaf spot. Highest disease severity recorded in genotypes Awassa 04 and PN13-1. Further research is needed in future to cover a wide range of environments and genotypes to screen high yielder and cercospora leaf spot disease resistance.

Seed inoculation with Rhizobium japonium bacteria improved fatty acid composition of different soybean (Glycine max L.) genotypes

BackgroundSoybean is an important crop for food security as it fulfills global oil requirements. Seed inoculation with bacteria is frequently used to increase its production; however, it could change the seed composition. Nevertheless, the genotypes respond differently to the bacteria. Therefore, it is necessary to assess the impact of Rhizobium bacteria on the seed composition. MethodsThis two-year (2018 and 2019) study investigated the effects of seed inoculation with Rhizobium japonicum on fatty acid composition of different soybean genotypes. Three frequently cultivated soybean genotypes, i.e., ‘Gapsoy16′, ‘Traksoy’, and ‘İlksoy’ were included in the study. The seeds were either inoculated with R. japonicum or sown without inoculation. The fatty acid profile, i.e., saturated fatty acids (palmitic and stearic acid) and unsaturated fatty acids (oleic, linoleic, linolenic, and arachidic acids) was determined, and the collected data were analyzed by single and multivariate analysis. ResultsSeed inoculation with R. japonicum significantly altered the fatty acid composition of different genotypes; however, varied effects were recorded for the genotype. Linoleic acid, oleic acid, and palmitic acid made up ∼ 33 % of total fatty acids in seeds. Linoleic acid contents varied between 30.78–34.02 %, whereas oleic acid contents ranged between 27.85–31.04 %. Similarly, palmitic acid contents differed between 15.53–16.93 %. The ‘İlksoy’ and ‘Gapsoy’ had the highest contents of palmitic and oleic acids, respectively. Overall, inoculation of bacteria increased the composition of unsaturated fatty acids and lowered saturated fatty acids. ConclusionSeed inoculation with R. japonicum increased the essential fatty acid composition in ‘Traksoy’ genotype. However, ‘İlksoy’ genotype recorded a decrease in unsaturated fatty acids. Therefore, ‘Traksoy’ can be inoculated with R. japonicum to improve fatty acid profile.

Intercropping Some Soybean Genotypes with Corn for Producing Soybean Seeds, Quality and Land Equivalent Ratios

Intercropping Some Soybean Genotypes with Corn for Producing Soybean Seeds, Quality and Land Equivalent Ratios

Deciphering the genetic basis of salinity tolerance in a diverse panel of cultivated and wild soybean accessions by genome-wide association mapping

Key messageIn a genome-wide association study involving 269 cultivated and wild soybean accessions, potential salt tolerance donors were identified along with significant markers and candidate genes, such as GmKUP6 and GmWRKY33.Salt stress remains a significant challenge in agricultural systems, notably impacting soybean productivity worldwide. A comprehensive genome-wide association study (GWAS) was conducted to elucidate the genetic underpinnings of salt tolerance and identify novel source of salt tolerance among soybean genotypes. A diverse panel comprising 269 wild and cultivated soybean accessions was subjected to saline stress under controlled greenhouse conditions. Phenotypic data revealed that salt tolerance of soybean germplasm accessions was heavily compromised by the accumulation of sodium and chloride, as indicated by highly significant positive correlations of leaf scorching score with leaf sodium/chloride content. The GWAS analysis, leveraging a dataset of 32,832 SNPs, unveiled 32 significant marker-trait associations (MTAs) across seven traits associated with salt tolerance. These markers explained a substantial portion of the phenotypic variation, ranging from 14 to 52%. Notably, 11 markers surpassed Bonferroni’s correction threshold, exhibiting highly significant associations with the respective traits. Gene Ontology enrichment analysis conducted within a 100 Kb range of the identified MTAs highlighted candidate genes such as potassium transporter 6 (GmKUP6), cation hydrogen exchanger (GmCHX15), and GmWRKY33. Expression levels of GmKUP6 and GmWRKY33 significantly varied between salt-tolerant and salt-susceptible soybean accessions under salt stress. The genetic markers and candidate genes identified in this study hold promise for developing soybean varieties resilient to salinity stress, thereby mitigating its adverse effects.

Beneficial or detrimental? How nickel application alters the ionome of soybean plants

The use of nickel (Ni) in agriculture may represent one of the most significant cases of plant hormesis ever reported, as plants exhibit both positive and negative responses depending on the level of exposure to this element. For a more comprehensive understanding of this effect, the next step is to conduct studies on the dynamics of pre-existing chemical elements in the system (ionomic profile), especially when introducing Ni as a novel nutrient for the plants. This micronutrient is of particular interest to the fertilization of leguminous plants, such as the soybean, due to its additional effects on the biological nitrogen fixation process. This study thus evaluated the influence of five doses of Ni (0.0, 0.5, 1.0, 3.0, and 9.0 mg of Ni kg−1) on the ionomic profile of soybean genotypes using modern quantification techniques. The results revealed that the addition of Ni reduced the concentration of cationic micronutrients manganese (Mn), iron (Fe), zinc (Zn), and copper (Cu), while it increased the concentration of macronutrients nitrogen (N) and magnesium (Mg). The application of Ni also resulted in a reduction of the potentially toxic element aluminum (Al). Correlations were also observed for these elements, indicating that Ni could be a controlling agent in elemental absorption and translocation. The ionome of the leaf tissues exhibited the most significant alterations, followed by the grains, nodules, and roots. Exogenous agronomic doses of Ni proved beneficial for the growth and production of soybean plants, although a genotypic effect was observed. The treatment with 9.0 mg of Ni kg−1, resulted in a new ionomic profile related to toxicity, demonstrating suboptimal plant development. Thus, the application of Ni in appropriate doses had a significant impact on the ionomic profile of soybeans, improving plant development and implying resistance to potentially toxic elements such as Al.