Soybean Research

Not AvailableSoybean is the world?s leading oilseed crop, important source of vegetable protein and demand for its seeds is increasing. Breeders have developed several widely cultivated varieties, but the genetic architecture of yield and key agronomic traits is poorly understood. In the present study, four widely cultivated soybean varieties and two exotic lines contrasting for various agro-morphological characters for crossing to develop four F2 populations viz., EC 538828 (PI 416999) x Young, JS 335 x Young, JS 95-60 x Young and JS 93-05 x JS 97-52. Significant differences are observed among the four F2 populations for all qualitative and quantitative characters under study. High coefficient of variation values was observed for many quantitative characters except for days to maturity, indicating presence of higher magnitude of variability for selection of these traits in subsequent generations for developing improved soybean cultivars. Segregation analysis of qualitative characters revealed major gene inheritance with monogenic control (for hypocotyl pigmentation, flower colour, leaf shape, pubescence, pubescence colour, pod colour, pod shattering) and digenic with various epistatic interactions (for growth habit, leaf shape, pubescence, pubescence colour, pod colour, pod shattering, seed lustre) in different crosses. Genetic control of various characters by major genes indicates scope for selection in the progenies of early generations to effectively manipulate these characters. Leaf let shape is found to be monogenic for oblong pointed being dominant over oval leaflet shape, but the ratio of 9:3:4 also observed, when lanceolate leaflet genotypes were crossed with broad leaflet shape parents in F2 population. Both 3:1 ratio and also 13:3 ratios observed for glabrous/pubescence among crosses. Pod shattering is found to be controlled by dominant inhibitory gene action

A Scintillating Journey of Genomics in Simplifying Complex Traits and Development of Abiotic Stress Resilient Chickpeas

Chickpea (Cicer arietinum L.) is an important cool season food legume cultivated in more than 55 countries across the globe. In the context of climate change, productivity of chickpea is hampered by higher incidence of abiotic and biotic stresses. Among abiotic stresses, drought, heat, cold and salinity are the most important yield limiting factors. Advanced genomics technologies have great potential to accelerate mapping, gene discovery, marker development and genomics-assisted breeding. Integration of precise phenotypic data along with sequence information will help in developing cultivars tolerant to various abiotic stresses. In this chapter, we discuss the impact of various abiotic stresses on chickpea production and provide an update on potential strategies to develop stress-tolerant chickpea cultivars. In addition, we also summarize the systematic efforts of simplifying the complex traits in chickpea as well as development of improved varieties with tolerance to abiotic stresses during last decade. In addition, we also highlight the emerging stresses and future strategies to combat the abiotic stresses

MutMap Approach Enables Rapid Identification of Candidate Genes and Development of Markers Associated With Early Flowering and Enhanced Seed Size in Chickpea (Cicer arietinum L.)

Globally terminal drought is one of the major constraints to chickpea (Cicer arietinum L.) production. Early flowering genotypes escape terminal drought, and the increase in seed size compensates for yield losses arising from terminal drought. A MutMap population for early flowering and large seed size was developed by crossing the mutant line ICC4958-M3-2828 with wild-type ICC 4958. Based on the phenotyping of MutMap population, extreme bulks for days to flowering and 100-seed weight were sequenced using Hi-Seq2500 at 10X coverage. On aligning 47.41 million filtered reads to the CDC Frontier reference genome, 31.41 million reads were mapped and 332,395 single nucleotide polymorphisms (SNPs) were called. A reference genome assembly for ICC 4958 was developed replacing these SNPs in particular positions of the CDC Frontier genome. SNPs specific for each mutant bulk ranged from 3,993 to 5,771. We report a single unique genomic region on Ca6 (between 9.76 and 12.96 Mb) harboring 31, 22, 17, and 32 SNPs with a peak of SNP index = 1 for low bulk for flowering time, high bulk for flowering time, high bulk for 100-seed weight, and low bulk for 100-seed weight, respectively. Among these, 22 SNPs are present in 20 candidate genes and had a moderate allelic impact on the genes. Two markers, Ca6EF10509893 for early flowering and Ca6HSDW10099486 for 100-seed weight, were developed and validated using the candidate SNPs. Thus, the associated genes, candidate SNPs, and markers developed in this study are useful for breeding chickpea varieties that mitigate yield losses under drought stress