Fusarium wilt caused by F. oxysporum f. sp. ciceris causes extensive damage to chickpea (Cicer arietinum L.) in many parts of the world. In the central part of India, pathogen race 2 (Foc 2) causes severe yield losses. We initiated molecular marker-assisted backcrossing (MABC) using desi cultivar, Vijay, as a donor to introgress resistance to this race (Foc2) in Pusa 256, another elite desi cultivar of chickpea. To confirm introgression of resistance for this race, foreground selection was undertaken using two SSR markers (TA 37 and TA110), with background selection to observe the recovery of recurrent parent genome using 45 SSRs accommodated in 8 multiplexes. F plants were confirmed with molecular markers and backcrossed with Pusa 256, followed by cycles of foreground and background selection at each stage to generate 161 plants in BCF during the period 2009-2013. Similarly, 46 BCF plants were also generated in another set during the same period. On the basis of foreground selection, 46 plants were found homozygotes in BCF. Among them, 17 plants recorded >91% background recovery with the highest recovery percentage of 96%. In BCF also, 14 hybrid plants recorded a background recovery of >85% with the highest background recovery percentage of >94%. The identified plants were selfed to obtain 1341 BCF and 2198 BCF seeds which were screened phenotypically for resistance to fusarium wilt (race 2) besides doing marker analysis. Finally, 17 BCF and 11 BCF lines were obtained which led to identification of 5 highly resistant lines of Pusa 256 with Foc 2 gene introgressed in them. Development of these lines will help in horizontal as well as vertical expansion of chickpea in central part of India.

Cultivation of the same varieties of mungbean and blackgram across different seasons and locations is constrained by their photo-and thermosensitive behaviour. Developing insensitive genotypes, which can fit well across all seasons, requires robust donors which would provide genes imparting this trait. This study was undertaken to identify such donors in the Vigna species. Forty-eight accessions belonging to 13 Vigna species and eight released cultivars were evaluated under natural field conditions. Among these, two accessions, viz. V. umbellata (IC251442) and V. glabrescens (IC251372) were found photo-and thermo-insensitive as these were able to flower and set pods at temperatures as high as 43.9°C and as low as 2.7°C. Pollen viability studies indicated viable pollen (>75% at 2.7°C and >85% at 41.9°C) and normal pollen tube growth at both the extremes of temperature. The identified V. glabrescens accession has long, constricted pods and dark green, mottled seeds while V. umbellata has smooth, curved pods and shining, oval, large seeds. Both these accessions can be utilized in developing photo-thermo insensitive genotypes in cultivated Vigna species.Key words: photo -thermo insensitivity -V. umbellata -V. glabrescens -wild VignaThe genus Vigna comprises more than 200 immensely variable species. Many of these are agronomically important and depict considerable economic and environmental importance. Amongare cultivated and consumed mostly in south and Southeast Asia and Africa. Many of the above species beside their high protein grains are valued as forage, green manure and cover crops. Mungbean and blackgram are the most popular and economically important crops of the Vigna group. India is the largest producer of these crops in the world and accounts for 65% of acreage and 54% of global production (Pratap et al. 2012). Keeping in view their short crop cycle, low input requirements and ability to survive in a wide range of adverse soil and climatic conditions, there is an ample scope of growing these crops across the seasons (spring, summer, winter and rainy seasons) in different parts of the country as a sole, relay or intercrop (Pratap et al. 2013). There is also a large scope of their further horizontal expansion in large areas, particularly in the rice fallows in peninsular India and in summer cultivation after the harvest of wheat, potato and rapeseed-mustard in Punjab, Haryana, Rajasthan and western Uttar Pradesh. However, the biggest hindrance in horizontal expansion of blackgram and mungbean in India is their photo-and thermo-sensitive nature which necessitates breeding of an array of genotypes for different agro-climatic zones of the country. Most of the varieties of mungbean and blackgram which have been bred till date are suitable only for a particular agro-climatic zone and cropping season. Nevertheless, most of the farmers usually recycle their seeds year after year and also across different seasons being unaware about the suitability of a particular variety in a specific season. In most of the...

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Genetic progress in quantitative traits can be improved by understanding how genes interact and estimating the consequences of combining abilities. As a result, a randomized block design with three replications was used to conduct forty crossings using a line X tester mating design with ten lines and four testers. All of the qualities were shown to be highly variable based on the ANOVA (analysis of variance) results among lines, testers, and hybrids. An estimated predictability ratio showed a high prevalence of nonadditive gene action, which was further confirmed by the lower narrow-sense heritability values for all traits. Most of the characters had high general combining ability and specific combining ability estimates, showing the relevance of both additive and nonadditive gene effects, respectively. For all of these features, however, the specific combining ability variations were greater than the general combining ability variances. Since heterosis breeding can lead to better hybrids, it may be a good idea to do so. For most yield-related parameters, such as fruit diameter, fruit per plant, marketable fruit per plant, yield per plant, marketable yield per plant, and total yield, RKML-26 and RKML-34 were the best general combiners among all lines. So, these lines might be employed as parents in hybridization programme in future to get suitable recombinants for higher fruit yield. However, the best cross combinations for commercial hybrid exploitation were RKML-26 X Pusa purple cluster (PPC) and RKML-2 X Swarna Shyamli. These crosses exhibiting higher per se performance and desirable specific combining ability effects together with either both or at least one parent as a competent combiner would be rewarding for heterosis breeding. Combining traditional breeding methods with biotechnological approaches, according to a new study, is critical for the transfer of favorable genes (traits) into farmed plants.