Soybean Plant Height Research Articles

Overexpression of GmNF-YA14 produced multiple phenotypes in soybean

Soybean is an important oil crop, and more and more soybean gene functions have been reported; however, one soybean gene with multiple functions is rarely seen. The NF-YA subfamily plays a broad regulatory role in plant growth and development, and GmNF-YA14 (Glyma.14G010000) is one of them. We found that the expression level of GmNF-YA14 in the root of soybean seedlings was significantly increased after a one-hour treatment with 200 mM salt. The transgenic soybean was obtained by Agrobacterium-mediated method, and all experiments were carried out using transgenic soybean homozygous lines. Under a 200 mM salt treatment, the leaf chlorophyll content of overexpressed GmNF-YA14 transgenic soybean seedlings was significantly decreased compared to the control. Moreover, the first flowering time of overexpressed GmNF-YA14 transgenic soybean was shortened by more than six days compared to the control, and the growth period structure changed significantly. Overexpressed GmNF-YA14 transgenic soybean plants had two or three branches, whereas control soybean plants had eight or nine branches. Compared to the control, the number of main stem nodes and plant height of overexpressed GmNF-YA14 transgenic soybean plants were significantly reduced. The 100-seed weight of GmNF-YA14 transgenic soybean line OE-8 was significantly higher than that of the control. Transcriptome analysis indicated that the multiple phenotypes of the overexpressed GmNF-YA14 transgenic soybean may be related to the mitogen-activated protein kinase (MAPK) signaling pathway. These results indicated that compared to the control, overexpressed GmNF-YA14 transgenic soybeans had changes in salt stress tolerance, growth period, plant type, and 100-seed weight, and these changes may be related to the MAPK signaling pathway.

Genome-wide survey identified superior and rare haplotypes for plant height in the north-eastern soybean germplasm of China

The proper and efficient utilization of natural genetic diversity can significantly impact crop improvements. Plant height is a quantitative trait governing the plant type as well as the yield and quality of soybean. Here, we used a combined approach including a genome-wide association study (GWAS) and haplotype and candidate gene analyses to explore the genetic basis of plant height in diverse natural soybean populations. For the GWAS analysis, we used the whole-genome resequencing data of 196 diverse soybean cultivars collected from different accumulated temperature zones of north-eastern China to detect the significant single-nucleotide polymorphisms (SNPs) associated with plant height across three environments (E1, E2, and E3). A total of 33 SNPs distributed on four chromosomes, viz., Chr.02, Chr.04, Chr.06, and Chr.19, were identified to be significantly associated with plant height across the three environments. Among them, 23 were consistently detected in two or more environments and the remaining 10 were identified in only one environment. Interestingly, all the significant SNPs detected on the respective chromosomes fell within the physical interval of linkage disequilibrium (LD) decay (± 38.9 kb). Hence, these genomic regions were considered to be four quantitative trait loci (QTLs), viz., qPH2, qPH4, qPH6, and qPH19, regulating plant height. Moreover, the genomic region flanking all significant SNPs on four chromosomes exhibited strong LD. These significant SNPs thus formed four haplotype blocks, viz., Hap-2, Hap-4, Hap-6, and Hap-19. The number of haplotype alleles underlying each block varied from four to six, and these alleles regulate the different phenotypes of plant height ranging from dwarf to extra-tall heights. Nine candidate genes were identified within the four haplotype blocks, and these genes were considered putative candidates regulating soybean plant height. Hence, these stable QTLs, superior haplotypes, and candidate genes (after proper validation) can be deployed for the development of soybean cultivars with desirable plant heights.

The Technical Parameters of Seaweed Biostimulant Spray Application as a Factor in the Economic Viability of Soybean Production

Application of biostimulant in the form of a spraying requires appropriate selection of technical parameters. One of the key factors in ensuring that the liquid is sprayed correctly is the choice of suitable spray nozzles. This study investigated selected technical parameters of seaweed biostimulant spray applications as a factor for plant biometrics, crop quality and yield, and the economic viability of production. This objective was achieved by conducting a two-year field experiment involving spraying soybean plants with a biostimulant containing seaweed extract. The spraying was carried out with two types of nozzles (standard and air-injector), for which the droplet size and the degree of plant coverage were tested at 4.0 MPa. The surface tension of the spray liquid and the area and volume of the droplets were tested. The height of soybean plants, the height and the position of the first pod, the number of pods, seed yield, and the weight of 1000 seeds were measured. The physical properties of the liquid sprayed on the plants and the type of nozzles used were factors affecting the height of the first pods, plant height, and protein content. The application of biostimulants using standard nozzles is more economically advantageous compared to nozzles with an air-injector.

Formation of the height of soybean plants using organic cultivation technology

Formation of the height of soybean plants using organic cultivation technology

Efeito do desbaste das árvores de eucalipto sobre rendimento da soja em sistemas de integração lavoura-pecuária-floresta

ABSTRACT: The aim of the study was to evaluate the effects of integrated crop-livestock-forestry (ICLF) systems and the thinning of eucalyptus trees on the agronomical performance of soybean. Treatments consisted of cultivation under: crops under full sunlight (CFS) conditions; ICLF with triple-row tree configuration (ICLFT) in which trees were submitted to selective thinning in the fifth year after planting through removal of 50% of trees while maintaining triple-row bands; and ICLF with single-row tree band configuration (ICLFS) in which the lateral rows of the triple-row tree bands were subjected to systematic thinning at the fourth year after planting. The physiological and agronomical variables of the soybean crop were evaluated at the R5 and R8 reproductive stages during the eighth harvesting season (2018/2019). Soybean sampling was carried out at five random positions in the CFS and in four transects at distances of 3, 6, 10 and 15 m from the tree bands in both the north and south faces of the ICLF systems. There were no differences between soybean grown under the ICLF and CFS systems with respect to specific leaf area, plant density, lodging index and mass of a thousand grains. However, the ICLF increased dry leaf mass and leaf area index and reduced soybean plant heights. Soybean productivity was reduced by 26% in ICLF-T and 14% in ICLF-S, that is, a 12% reduction in the productivity loss with systematic thinning. It is concluded that ICLF reduces soybean productivity in the effective grain production area of the system, regardless of the degree of thinning, although systematic thinning by removing the lateral tree lines to conversion of triple-rows into single-rows minimizes the loss of soybean grain yield.

Effects of Flooding Duration and Growing Stage on Soybean Growth Based on a Multi-Year Experiment

Flood stress on crops severely constrains food production. From 2011 to 2018, a plot test was conducted to investigate the effects of flooding duration and growth stage on soybean plant height, the number of solid pods, 100-grain weight, yield, and dry matter mass, and their interannual variation. The results showed that the soybean indicators were significantly influenced by the year, flooding duration and growth stage, and their interaction. Under the same flooding duration and growth stage, the smallest plant height, number of solid pods, 100-grain weight, and dry matter mass were observed in 2016; and the largest plant height, number of solid pods, yield, and dry matter mass were observed in 2011. The soybean critical flooding duration for the number of solid pods, yield, and dry matter mass was 3 days, and that for 100-grain weight was 6 days. The flooding duration had no significant effect on plant height. The flooding-sensitive growth stage for soybean plant height and dry matter mass was the seedling stage, and that for the number of solid pods, 100-grain weight, and yield was the flowering-podding stage. When investigating the effects of flooding stress on soybeans, the impacts of interannual variation such as high temperatures and drought on soybean growth and yield should be integrated.

Effect of cashew (Anacardium occidentale) biochar on soil chemical properties and agronomy of soybean (Glycine max L. merril)

The experiments were conducted at the Teaching and Research Farm, Faculty of Agriculture, Nasarawa State University, Keffi, Shabu-Lafia during the 2018 and 2019 cropping seasons to evaluate the effects of different levels of biochar on soil properties, growth and yield of soybean. The experiments were laid in Randomized Complete Block Design (RCBD) with three replications. Biochar at the rates of 0, 4, 8 and 12 tons/ha were incorporated into the ridges of soybean at planting. The results showed that soil organic matter, organic carbon, total nitrogen, potassium, available phosphorus, calcium, sodium and base saturation decreased with soil layers. Soil pH (4.67 and 4.69), magnesium (1.52 and 1.62 cmol/kg), exchangeable acidity (0.67 and 0.75 cmol/kg) and cation exchange capacity (5.18 and 5.23 cmol/kg) increased with soil depth. Biochar at the rate of 12 tons/ha showed consistently the highest values of soil properties over other rates. The results also showed that biochar at the rate of 8 tons/ha recorded significantly (p<0.05) the tallest soybean plant height at 8 weeks (40.4 and 42.7 cm) and 10 (43. 0 and 49.2 cm) after planting in 2018 and 2019 cropping seasons respectively while the highest number of branches (4.5 and 4.5) was recorded in 2018 cropping season only. The results further revealed that biochar at the rate of 8 tons/ha recorded the highest weight per 100 seed (16.9 and 14.9 g) and seed yield (1304.0 and 1316.7 kg) per hectare in both cropping seasons. From the results of this study, it can be concluded that biochar at the rates of 12 and 8 tons/ha positively influenced soil and soybean plant parameters evaluated. Therefore, biochar at the rate of 8 tons/ha is considered as the optimum rate for sustainable soybean production in the study area.

Evaluation of Rearing Factors Affecting Clanis bilineata tsingtauica Mell Larvae Fed by Susceptible Soybean Variety NN89-29 in Spring and Autumn Sowing.

Clanis bilineata tsingtauica Mell is a nutritious edible insect. In the present study, soybean variety NN89-29 susceptible to leaf-feeding insects was used as the experiment material to evaluate the rearing factors affecting the production of C. bilineata tsingtauica in spring and autumn sowing. We artificially inoculated C. bilineata tsingtauica eggs to soybean plants, and the relevant indexes of larvae and soybean plants were recorded. The main results from spring sowing were as follows: (1) Larval number, single larval weight and plot-larval weight were all higher in the V6 stage (sixth trifoliolate) than those in the R3 stage (beginning pod) of inoculated eggs. (2) Larval number, single larval weight and plot-larval weight significantly decreased under higher planting density. Meanwhile, the soybean plant height and internode length increased, while the main stem node number of soybean decreased under higher planting density. (3) Single larval weight and plot-larval weight were not significantly affected by different numbers of eggs inoculated, but the larval number was significantly affected. Under autumn sowing conditions: (1) The larvae production and soybean plant growth were not significantly affected by covering the top of the net house with plastic film to isolate rainwater. (2) More eggs inoculated were associated with higher plot-larval weight. Conversely, fewer eggs inoculated resulted in a higher proportion of single larvae weight more than or equal to 6 g (≥6 g). Compared to spring sowing, the low biomass of autumn-sown soybean plants did not provide sufficient food for C. bilineata tsingtauica growth, and competition for food resulted in lower larval number, single larval weight and plot-larval weight.

Response of Soybean (Glycine max (L.) Merr.) and Weed Control with Postemergence Herbicides and Combinations of Cytokinin Mixtures

A field study was conducted in 2015 and 2016 in Stoneville, MS, to evaluate the influence of cytokinin products on soybean injury and weed control when combined with common POST soybean herbicide treatments. Cytokinin treatments included no cytokinin mixture and two formulated cytokinin mixtures (kinetin-1 and kinetin-2) applied at 0.000227 kg ai ha−1. Herbicide treatments were no herbicide, glyphosate at 1.37 kg ae ha−1 alone and in combination with S-metolachlor at 1.42 kg ai ha−1 or fomesafen 0.395 kg ai ha−1. The addition of cytokinin treatments had no impact on soybean injury, plant height, or yield. Glyphosate plus fomesafen provided the greatest level of Palmer amaranth control, between 84 and 67%., 7 days and 28 days after treatment, respectively. Barnyardgrass control with glyphosate plus fomesafen was antagonized by one of two cytokinin products. To prevent possible reductions in herbicide efficacy, tank mixtures with cytokinin products should not be applied to soybean in POST herbicide applications.

Identification of endophytic fungi with ACC deaminase-producing isolated from halophyte Kosteletzkya Virginica

ABSTRACT Seashore mallow (Kosteletzkya virginica), as a noninvasive perennial halophytic oilseed-producing dicot, is native from the Gulf to the Atlantic coasts of the U.S. The purpose of our research was to investigate 1-aminocyclopropane-1carboxylic acid deaminase (ACCD) producing endophytic fungi from K.virginica. A total of 59 endophytic fungal strains, isolated from roots in K.virginica of seedlings, were grouped into 12 genera including in Penicillium, Aspergillus, Fusarium, Trichoderma, Rhizopycnis sp., Ceriporia Donk, Trametes sp., Schizophyllum commune sp., Alternaria, Cladosporium, Cylindrocarpon, and Scytalidium according to sequences of ITS. The ACD activity of 10 endophytic fungi isolated was detected. T.asperellum had the highest ACC deaminase activity among all 10 isolated genera of fungal strains, followed by T. viride. Dry weight and fresh weight of plant, plant height, root length, SOD activity, and chlorophyll content of wheat and soybean inoculated with T.asperellum or T. viride was increased compared with non-inoculated control plants under non salt or salt stress. Further analysis showed that T.asperellum or T.viride strains induced downregulation of the expression of ethylene synthesis-related genes such as ACC oxidase (ACO) and ACC synthase (ACS), thereby reducing ethylene synthesis and damage to plants under salt stress. These endophytic fungi can be used as alternative bioinoculants to increase crop yield in saline soil.

Pengaruh Posisi Pemangkasan Daun Jagung Dalam Sistem Tumpang Sari Terhadap Pertumbuhan dan Hasil Kedelai

This study aims to determine the effect of corn leaf pruning on soybean growth and yield in an intercropping system. This research was carried out on farmers' land in Simpang Village, Berbak District, Tanjung Jabung Timur Regency from July - October 2020. This research was carried out using a Randomized Block Design (RBD) with 5 replications. Pruning treatments based on the position of the leaves on the stem were : without pruning (control/p0), pruning 3 leaves at a position near the soil surface (p1), pruning 3 leaves at a position below the cob (p2), and pruning 3 leaves at a position above the cob (p3). The variables observed included soybean plant height (cm), number of pods per plant, number of filled pods per plant, weight of 100 dry seeds (g), and soybean dry seed yield. The results showed that the highest soybean plant height was obtained without pruning and pruning 3 corn leaves near the soil surface, but produced the lowest number of pods per plant, number of filled pods, and the lowest soybean dry seed yield. The number of pods per plant, the number of containing per plant, and the highest soybean dry seed yield were obtained at pruning of 3 leaves under the cob and 3 leaves of corn above the cob. In corn, the highest yield was obtained by pruning 3 leaves below the cob and 3 leaves above the cob. The diversity of soybean dry seed yields in this study was determined jointly by the diversity of the number of pods per plant, the number of filled pods per plant, and the weight of 100 dry seeds. Partially, only the number of pods contained per plant and the weight of 100 dry seeds significantly played a role in determining the amount of dry soybean yield, while the number of pods per plant had no significant role in determining the diversity of dry seed yields. Land use with corn and soybean intercropping system can increase land productivity so that it is more efficient with LER value > 1 in all positions of corn leaf pruning. Keywords: pruning, intercropping corn, soybean

An APETALA2/ethylene responsive factor transcription factor GmCRF4a regulates plant height and auxin biosynthesis in soybean.

Plant height is one of the key agronomic traits affecting soybean yield. The cytokinin response factors (CRFs), as a branch of the APETALA2/ethylene responsive factor (AP2/ERF) super gene family, have been reported to play important roles in regulating plant growth and development. However, their functions in soybean remain unknown. This study characterized a soybean CRF gene named GmCRF4a by comparing the performance of the homozygous Gmcrf4a-1 mutant, GmCRF4a overexpression (OX) and co-silencing (CS) lines. Phenotypic analysis showed that overexpression of GmCRF4a resulted in taller hypocotyls and epicotyls, more main stem nodes, and higher plant height. While down-regulation of GmCRF4a conferred shorter hypocotyls and epicotyls, as well as a reduction in plant height. The histological analysis results demonstrated that GmCRF4a promotes epicotyl elongation primarily by increasing cell length. Furthermore, GmCRF4a is required for the expression of GmYUCs genes to elevate endogenous auxin levels, which may subsequently enhance stem elongation. Taken together, these observations describe a novel regulatory mechanism in soybean, and provide the basis for elucidating the function of GmCRF4a in auxin biosynthesis pathway and plant heigh regulation in plants.

GmIAA27 Encodes an AUX/IAA Protein Involved in Dwarfing and Multi-Branching in Soybean.

Soybean plant height and branching affect plant architecture and yield potential in soybean. In this study, the mutant dmbn was obtained by treating the cultivar Zhongpin 661 with ethylmethane sulfonate. The dmbn mutant plants were shorter and more branched than the wild type. The genetic analysis showed that the mutant trait was controlled by a semi-dominant gene. The candidate gene was fine-mapped to a 91 kb interval on Chromosome 9 by combining BSA-seq and linkage analysis. Sequence analysis revealed that Glyma.09g193000 encoding an Aux/IAA protein (GmIAA27) was mutated from C to T in the second exon of the coding region, resulting to amino acid substitution of proline to leucine. Overexpression of the mutant type of this gene in Arabidopsis thaliana inhibited apical dominance and promoted lateral branch development. Expression analysis of GmIAA27 and auxin response genes revealed that some GH3 genes were induced. GmIAA27 relies on auxin to interact with TIR1, whereas Gmiaa27 cannot interact with TIR1 owing to the mutation in the degron motif. Identification of this unique gene that controls soybean plant height and branch development provides a basis for investigating the mechanisms regulating soybean plant architecture development.

Respons Pertumbuhan dan Serapan N Tanaman Kedelai (Glycine max L. Merrill) dengan Pemberian Bradyrhizobium sp. dan Kapur di Tanah Mineral Masam

People's purchasing power for animal protein has decreased and has shifted to processed soy foods as one of the foods containing vegetable protein during the Covid-19 pandemic due to the economic recession. Soybeans are a source of high vegetable protein so they require a lot of Nitrogen (N). To fulfill the demand for soybeans, soybean cultivation can be carried out in acidic mineral soils with a low pH. Acidic mineral soil with a low pH causes it difficult for N nutrients to be available and the bacteria <em>Bradyrhizobium</em> sp. difficult to symbiosis with soybean plants. The aim of this study was to increase the growth and N uptake of soybean plants on acid mineral soils by inoculating <em>Bradyrhizobium</em> sp. and lime. The research was conducted in Jati Kesuma Village, Namorambe, Deli Serdang on a plot size 200 x 200 cm using a factorial randomized block design (RAK) with 2 factors. The first factor was the inoculating of <em>Bradyrhizobium</em> sp inoculants consisting of without inoculant; BGR 3 inoculant; and LP 3 inoculant. The second factor was liming consisting of without liming and liming with a dose of 1.06 kg/plot (pH 4.9 to 5.5). The results showed that <em>Bradyrhizobium</em> sp. BGR 3 inoculant tended to increase soybean plant height on acid mineral soil, but LP 3 inoculant was able to increase shoot root ratio and tended to increase N uptake 62.86% on acid mineral soil. The addition of lime was able to increase the growth of soybean plants on acidic mineral soil and increased N uptake 4.08%. The combination of LP 3 inoculant and without liming was able to increase shoot root ratio of soybean 133,33% on acid mineral soils.

Silicon Enhances Plant Vegetative Growth and Soil Water Retention of Soybean (Glycine max) Plants under Water-Limiting Conditions.

Silicon has been implicated as a factor affecting the degree of resistance to abiotic stresses in several plant species. However, the role of silicon in soybean (Glycine max) under water-limiting conditions is not yet fully understood. This study was conducted to evaluate the effects of silicon application on the vegetative growth of two soybean cultivars (Asgrow 5332 and Progeny 5333) grown under water-limiting conditions. Silicon was provided by adding silicate to the soil. Water-limiting treatments were imposed on plants at two vegetative growth stages for 20 days by irrigating with a reduced amount of water (66% or 33% of the required water). Silicate application enhanced plant height, leaf area, and total dry weight of soybean plants. Significant increases in root volumes were observed in both the silicate-treated cultivars compared to the control plants under water-limiting conditions (33% irrigation). Net photosynthesis and stomatal conductance were decreased, but the quantum efficiency of photosystem II (Fv’/Fm’) did not change under the same irrigation condition, which indicates photosynthesis downregulation through stomatal limitation. Silicate-treated plants in both cultivars had higher water use efficiency as compared to control plants under water-limiting conditions (irrigated with 66% or 33% of required water). Under water-limiting conditions, the soil moisture content was significantly higher in pots containing silicate than in those without added silicate, suggesting that silicon application improves water holding capacity. Taken together, the results from this study indicate that silicon application can improve the vegetative growth of soybeans under low water conditions by increasing the water use efficiency of plants and enhancing the soil’s ability to retain moisture.

Identification of Low-Light-Resistant Germplasm and Related Loci of Soybean

Low-light stress will lead to abnormal soybean growth and a subsequent yield reduction. Association mapping is a useful alternative to linkage mapping for the detection of marker–phenotype associations. This study aimed to evaluate low-light-resistant soybean accessions and identify markers associated with low-light resistance. We assessed the plant height, stem diameter, number of bean pods, and cotyledon height of soybean plants under low and normal light conditions. These traits were evaluated in 185 soybean accessions, and the accessions 11HX-020, 11HX-025, 11HX-029, 11HX-064, 11HX-127, 11HX-166, 11HX-183, and 11HX-216 showed stable performance under low-light conditions. These 185 accessions were genotyped with 639 single-nucleotide polymorphism (SNP) markers and 98 simple sequence repeat (SSR) markers. A total of 75 markers—i.e., traits associated with low-light resistance—were identified. These associated markers were distributed on 14 linkage groups (LGs) of soybean, and some markers were associated with two or more traits. According to the results, excellent germplasm material and low-light-resistance related markers can be used for low-light resistance breeding of soybean and will help identify the low-light resistance genes.

Identification and characterization of long-InDels through whole genome resequencing to facilitate fine-mapping of a QTL for plant height in soybean (Glycine max L. Merr.)

With the development of sequencing technology, insertions-deletions (InDels) have been increasingly reported to be involved in the genetic determination of agronomical traits. However, most studies have focused on the identification and application of short-InDels (1–15 bp) for genetic analysis. The objective of this study was to deeply deploy long-InDels (>15 bp) for the genetic analysis of important agronomic traits in soybean. A total of 13 573 polymorphic long-InDels were identified between parents Zhongpin 03-5373 (ZP) and Zhonghuang 13 (ZH), which were unevenly distributed on 20 chromosomes of soybean, varying from 321 in Chr11 to 1 246 in Chr18. Consistent with the distribution pattern of annotated genes, the average density of long-InDels in arm regions was significantly higher than that in pericentromeric regions at the P=0.01 level. A total of 2 704 (19.9% of total) long-InDels were located in genic regions, including 319 large-effect long-InDels, which resulted in truncated or elongated protein sequences. A previously identified QTL (qPH16) underlying plant height was further analyzed, and it was found that 26 out of 35 (74.3%) long-InDel markers located in the qPH16 region showed clear polymorphisms between parents ZP and ZH. Seven markers, including three long-InDels and four previously reported SNP markers, were used to genotype 242 recombinant inbred lines derived from ZP×ZH. As a result, the qPH16 locus was narrowed from a 960-kb region to a 477.55-kb region, containing 65 annotated genes. Therefore, these long-InDels are a complementary genetic resource of SNPs and short-InDels for plant height and can facilitate genetic studies and molecular assisted selection breeding in soybean.

Performance of soybean crop in response to palisadegrass pasture desiccation and nitrogen fertilization under integrated crop-livestock system

The desiccation (burn down) time of high-biomass pasture in no-tillage system and nitrogen (N) fertilization of pasture and soybean can influence the crop performance under crop-livestock system. The objective of this study was to evaluate the effect of desiccation times of palisadegrass pasture combined with three N fertilization levels of pasture and two N fertilization levels of soybean on crop yield, yield components and grain oil and protein concentration. Three N rates in the U. brizantha cv. BRS Piatã pasture were evaluated (0; 150 and 300 kg ha-1 of N as urea) in three different experiments. In each experiment, five pasture desiccation periods (60; 45; 30; 15 and 1 days before soybean sowing) and two levels of N fertilization of soybean (30 kg ha-1 of N distributed as urea at sowing + a control without urea) were evaluated. A randomized complete block design with five replications was used for each experiment. After statistical analysis of each experiment, a joint analysis of the three experiments was performed, allowing the comparison of the three rates of N in the pasture. The time interval between Urochloa brizantha pasture desiccation and soybean sowing did not influence soybean yield, yield components or the grain oil and protein concentrations, regardless of N fertilization of pasture and soybean. N fertilization of pasture induced a taller soybean plant height, insertion height of first pod, increased lodging, and reduced yield, but did not change the grain oil and protein concentration, regardless of the pasture desiccation time and N fertilization of soybean. Soybean grain yield was negatively affected by N fertilization of the crop, regardless of fertilization levels and desiccation times of the previous pasture

Identification of superior haplotypes in a diverse natural population for breeding desirable plant height in soybean

Key messagePlant height of soybean is associated with a haplotype block on chromosome 19, which classified 211 soybean accessions into five distinct groups showing significant differences for the target trait.Genetic variation is pivotal for crop improvement. Natural populations are precious genetic resources. However, efficient strategies for the targeted utilization of these resources for quantitative traits, such as plant height (PH), are scarce. Being an important agronomic trait associated with soybean yield and quality, it is imperative to unravel the genetic mechanisms underlying PH in soybean. Here, a genome-wide association study (GWAS) was performed to identify single nucleotide polymorphisms (SNPs) significantly associated with PH in a natural population of 211 cultivated soybeans, which was genotyped with NJAU 355 K Soy SNP Array and evaluated across six environments. A total of 128 SNPs distributed across 17 chromosomes were found to be significantly associated with PH across six environments and a combined environment. Three significant SNPs were consistently identified in at least three environments on Chr.02 (AX-93958260), Chr.17 (AX-94154834), and Chr.19 (AX-93897200). Genomic regions of ~ 130 kb flanking these three consistent SNPs were considered as stable QTLs, which included 169 genes. Of these, 22 genes (including Dt1) were prioritized and defined as putative candidates controlling PH. The genomic region flanking 12 most significant SNPs was in strong linkage disequilibrium (LD). These SNPs formed a single haplotype block containing five haplotypes for PH, namely Hap-A, Hap-B, Hap-C, Hap-D, and Hap-E. Deployment of such superior haplotypes in breeding programs will enable development of improved soybean varieties with desirable plant height.

Identification of Genomic Regions Associated with Vine Growth and Plant Height of Soybean.

Vining growth (VG) and high plant height (PH) are the physiological traits of wild soybean that preclude their utilization for domesticated soybean breeding and improvement. To identify VG- and PH-related quantitative trait loci (QTLs) in different genetic resources, two populations of recombinant inbred lines (RILs) were developed by crossing a cultivated soybean, Zhonghuang39 (ZH39), with two wild soybean accessions, NY27-38 and NY36-87. Each line from the two crosses was evaluated for VG and PH. Three QTLs for VG and three for PH, detected in the ZH39 × NY27-38 population of the RILs, co-located on chromosomes 2, 17 and 19. The VG- and PH-related QTL in the ZH39 × NY36-87 population co-located on chromosome 19. A common QTL shared by the two populations was located on chromosome 19, suggesting that this major QTL was consistently selected for in different genetic backgrounds. The results suggest that different loci are involved in the domestication or adaptations of soybean of various genetic backgrounds. The molecular markers presented here would benefit the fine mapping and cloning of candidate genes underlying the VG and PH co-localized regions and thus facilitate the utilization of wild resources in breeding by avoiding undesirable traits.