Sanjeev Gupta

Legumes in the omic era

Ch. 1. Legumes in Omic Era: Retrospects and Prospects Ch. 2. Advances in Functional Genomics in Legumes.- Ch. 3. Advances in Soybean Genomics.- Ch. 4. Advances in Chickpea Genomics.- Ch. 5. Advances in Pigeonpea Genomics.- Ch. 6. Advances in Lentil Genomics.- Ch. 7. Advances in Cowpea Improvement and Genomics.- Ch. 8. Advances in Greengram and Blackgram Genomics.- Ch. 9. Common Bean Genomics and its Applications in Breeding Programs.- Ch. 10. Pulses biofortification in genomic era: multidisciplinary opportunities and challenges.- Ch. 11. Towards Enriching Genomic Resources in Legumes.- Ch. 12. Bioinformatics for Legume Genomics Research.- Ch. 13. Genetics and genomics of resistance to rust and stemphylium blight in lentil.- Ch. 14. Genomics in studying the legume genome evolution.- Ch. 15. Advances in Pea Genomics

Biotechnological Interventions in Host Plant Resistance

abstract Host plant resistance forms an integral part of integrated pest management. Conventional host plant resistance is slow and difficult to achieve due to the involvement of quantitative traits at several loci. However, recent biotechnological interventions have opened up new opportunities for pest control by providing an access to novel molecules, ability to change the level and pattern of expression of genes and development of transgenic varieties with insecticidal genes. Several transgenics have been developed in a number of crop plants including corn, rice, cotton, canola, soybean, tobacco, apple, potato and many others that have genes for δ-endotoxins from Bacillus thuriengiensis Berliner. The economic and environmental impact of adoption of such crops has been huge and it has led to a significant reduction in the global environmental impact of production agriculture. However, the reports on the development of insect resistance to the δ-endotoxins from Bt have raised questions on the sustainability of Bt-based pest management strategies. Gene-pyramiding, which comprises stacking of multiple genes and leads to simultaneous expression of more than one toxin in the transgenic variety, has been advocated as one of the solutions though it is also associated with problems such as development of cross- and multiple resistances. Further, possible environmental and ecological impacts, particularly gene-flow and effect on non-target organisms pose more serious questions and need to be addressed properly before the commercialization of a transgenic variety. This chapter focuses on the recent developments in insect-resistant transgenic varieties and their impact as well as the problems associated with them.

Field characterization of endemic wild Vigna accessions collected from biodiversity hotspots of India to identify promising genotypes for multiple agronomic and adaptive traits

Wild Vigna species possess a reservoir of useful genes that have potential to be utilized in improvement of cultivated mungbean and urdbean. The level of genetic diversity in representative accessions of cultivated and wild Asiatic Vigna species collected from diversity-rich endemic areas of India was investigated using morphological descriptors. Data were recorded on 27 qualitative and quantitative traits in 44 wild and cultivated accessions belonging to 12 Vigna species grown over 2 years and analyzed to compute mean and variances for each trait. Cluster analysis following unweighted pair group method based on arithmetic mean grouped accessions into five clusters with cluster I accommodating most of the accessions. The different accessions showed variation at species level based on morphological descriptors. 3 accessions viz., IC251424 and IC251425 of V. radiata and IC331436 of V. trilobata were superior for multiple traits viz., number of seeds/pod, seed quality and early maturity. Likewise for seed size, IC 298665 of V. unguiculata and PRR 2008-2 of V. umbellata were identified as promising donors while for earliness, 3 accessions of V. trilobata (IC 331545, IC 349701 and JAP/10-7), 1 of V. radiata (IC 251427) and 1 each of V. mungo (IC 251385) and V. unguiculata (IC 298665) were identified as maturing significantly early and therefore, could be used in hybridization programme for introgression of these traits. This evaluation and characterization study on endemic Vigna species provides useful information for improving mungbean and urdbean cultivars through recombination breeding.

Biplot evaluation of test environments and identification of lentil genotypes with durable resistance to fusarium wilt in India

Abstract. Fusarium wilt (caused by Fusarium oxysporum f. sp. lentis) is the most crucial limiting variable for decreasing yield levels of lentils (Lens culinaris Medik.) around the world. A set of 20 diverse lentil genotypes comprising breeding lines and released varieties was evaluated, along with susceptible controls, for resistance to fusarium wilt through natural incidence for two continuous years (2010–11 and 2011–12) in six diverse lentil-growing environments in India. Analysis of variance showed that the effect of genotype (G) and environment (E) for disease incidence was highly significant. Among the three sources of variation, the biggest contribution in disease occurrence was accounted for by environment (54.68%), followed by G × E interaction (17.32%). The high G × E variation necessitated assessment of the genotypes at different locations (environments). GGE biplot analysis of the studied genotypes revealed that genotype PL 101 and released cultivar L 4076 had low levels of disease incidence. The sources of resistance to fusarium wilt have great potential for use in lentil-breeding programs. Another biplot of relationships among environments demonstrated that, among the test locations, Sehore and Faizabad, were the most effective for differentiation of genotypes. On the basis of discriminating ability and representativeness, the Sehore location appeared an ideal testing site for natural incidence of F. oxysporum f. sp. lentis.

Enhancing pulses production in India through improving seed and variety replacement rates

India is the largest producer, consumer and importer of pulses in the world. Pulses are important for the nutritional security of the cereal based vegetarian diet of large population of India. Due to ever increasing population, rising income of people and pulses being the major source of protein in Indian diet, the demand for pulses continues to grow at 2.8% per annum. It is estimated that 27.5 million tonnes of pulses would be required by 2025. Since more than 80% of the area under pulses is under stressed rainfed environment, the quality seed of improved varieties has emerged as the most vital input for enhancing pulses production in India. For ensuring availability of quality seed it was estimated that 39.38 lakh q and 46.87 lakh q quality seed of improved varieties would be required in 2020 and 2025, respectively, at increased seed replacement rate (SRR). The SRR of all the pulses under study showed an increasing trend during the last decade. This could be further increased with vibrant formal and informal seed system involving public and private seed industries and promotion of participatory seed production programmes. Since pulses are grown in diverse agro-climatic situations under severe biotic and abiotic stresses, the varietal diversity in seed chain also assumes greater importance. Seed chain is currently being maintained with 236 improved varieties of six major pulses. However, only 44 of them occupied prominence in seed chain and could contribute significantly to increased pulse production in recent times. There is further need to bring sufficient number of high yielding and disease resistant varieties in seed chain which should adequately represent all pulse growing areas in the country. The present paper discusses the options of yield enhancement in pulses through increased availability of quality seed and strategy for enhancing variety replacement, rate (VRR) and seed replacement rate (SRR) of major pulses, viz., chickpea (Cicer arietinum L.), pigeonpea (Cajanus cajan L.), mungbean (Vigna radiata L. Wilczek), urdbean (Vigna mungo L. Hepper), lentil (Lens culinaris L.) and fieldpea (Pisum sativum L.)

Inheritance of mutant and wild type leaf shape in greengram(Vigna radiata)and blackgram(Vigna mungo)

Leaf shape is an important phenotypic trait in Vigna spp. and to find out the inheritance of different leaf shape types in greengram (Vigna radiata L. Wilczek) and blackgram (Vigna mungo L. Hepper) intervarietal crosses were made among different leaf shape type bearing genotypes of greengram and blackgram during rainy season of year 2007. F2 and F3 populations are grown during rainy season of 2008 and 2009, respectively and they are phenotyped for the trait under study. Mendelian inheritance of ovate leaf shape in greengram and lanceolate leaf shape in blackgram was found to be controlled by single recessive gene in the entire cross combinations. The proposed gene symbols for leaf shape in greengram and blackgram are ov and OV, respectively. Since leaf shape is distinct morphological feature and is in case simply inherited, hence this can be used as potential phenotypic marker in genetic studies.