Inheritance studies through generation mean analysis for quantitative traits in soybean (Glycine max (L.) Merrill.)

Most of the economically important traits in soybean are quantitatively inherited. The generation mean analysis involving a five-parameter model was carried out in four crosses, viz., Pratap Soya- 2 × LP 5-2, Co 3 × LP 5-2, Co 3 × LP 5-1 and Co 3 × LP 13-1 to investigate additive, dominance and epistatic variance. Therefore, F1, F2 and F3 generations of the above four crosses were evaluated along with their respective parents to estimate the gene action for eleven quantitative traits through generation mean analysis, which provides information about all the gene interactions. The crosses Co 3 × LP 5-1 and Co 3 × LP 13-1 for plant height, Pratap Soya-2 × LP 5-2 for protein content and Co 3 × LP 5-2 for both oil content and seed yield per plant exhibited the adequacy of the additive dominance model. The remaining crosses exhibited epistatic interactions with all other traits. Hence simple recurrent selection can be followed to increase the frequency of desirable genes in the population and the resulted improved population can be used to develop superior lines with desirable genes by pedigree breeding. The crosses Co 3 × LP 5-1 and Pratap Soya - 2 × LP 5-2 were best for further selection programmes with regard to seed yield and quality improvement

Assessment of stableness for male sterility in newly developed CMS lines in sunflower (Helianthus annuus L.)

Diversification of parental lines both CMS and restorer inbreds are the absolute necessities in sunflower heterosis breeding programme for developing hybrids with high yield, high oil content as well as biotic and abiotic stress resistance. A total of 11 inbred lines with high oil content and high yield from TNHSF 239 population and also promising inbreds from a three way cross (TNHSF 239 x Wild 1-3-2) x Morden derivatives were utilized in conversion programme for developing new CMS lines in sunflower. Eleven newly developed CMS lines from BC6 back cross population were evaluated for their stability across three locations namely Coimbatore, Vamban and Chettinad. All the CMS lines except COSF8A and COSF 9A exhibited stable sterility across the locations and all the maintainers showed 100% fertility at all the three locations. Three CMS lines namely COSF 6A, COSF 7A and COSF 12A were identified for their high oil content (40-43%). Hybrids of these CMS lines showed positive heterosis for yield and yield attributing traits. Therefore, newly developed promising CMS lines can be effectively utilized in hybrid breeding programme for developing high yielding and high oil hybrids in sunflower

A record on the insect pests of wild relatives of pigeonpea, mungbean and urdbean

Integrated approaches are being followed for the management of pests in the present world. One of the components in IPM is the use of host plant resistance, which can be easily adopted by the farmers with a cheaper cost. For the identification and development of resistance sources, wild relatives of different cultivated species are being employed. This kind of approaches are being followed in the legume improvement programme also. One of the major limiting factors in pulse production is the pest complex, which inflicts heavy yield loss. The major legume insect pests are the gram pod borer Helicoverpa armigera Hubtter, pod fly Melanagromyza obtusa, spotted pod borer Maruca vitrata Geyer and pod bugs Clavigralla gibbosa Spinola, Riptortus spp. and blister beetle, Mylabris sp. (Durairaj 1999). The gram pod borer is the most devastating pest of pigeonpea, which cause worldwide yield loss of more than $317 million annually (Shanower et al. 1999). As there was low level of resistance in cultivated types of pigeonpea, the search for resistance sources has been included on non-cultivated Cajanus sp. also (Lateef et al. 1981)

IPH 732 - The First Pigeonpea Hybrid for Tamil Nadu, India

Pigeon pea (Cajanus cajan) hybrid IPH732, developed from a cross between male sterile T21 and ICPL87109, was evaluated in multilocational trials during 1990/91 and in adaptive research trials (ART) during the rainy season of 1992. Overall in multilocational trials, ART, station and national trials, IPH732 had a mean yield of 0.94 t/ha, which was 49 and 41% more than ICPH8 and ICPL87, respectively. IPH732 has an indeterminate growth habit, matures in 115-120 days, and is suitable for irrigated and rainfed conditions. It has good cooking quality and seeds contain 22.3% protein. It was released for cultivation in Tamil Nadu as CoH1

Grain Nutrients Variability in Pigeonpea Genebank Collection and Its Potential for Promoting Nutritional Security in Dryland Ecologies

Pigeonpea, a climate-resilient legume, is nutritionally rich and of great value in Asia, Africa, and Caribbean regions to alleviate malnutrition. Assessing the grain nutrient variability in genebank collections can identify potential sources for biofortification. This study aimed to assess the genetic variability for grain nutrients in a set of 600 pigeonpea germplasms conserved at the RS Paroda Genebank, ICRISAT, India. The field trials conducted during the 2019 and 2020 rainy seasons in augmented design with four checks revealed significant differences among genotypes for all the agronomic traits and grain nutrients studied. The germplasm had a wider variation for agronomic traits like days to 50% flowering (67-166 days), days to maturity (112-213 days), 100-seed weight (1.69-22.17 g), and grain yield per plant (16.54-57.93 g). A good variability was observed for grain nutrients, namely, protein (23.35-29.50%), P (0.36-0.50%), K (1.43-1.63%), Ca (1,042.36-2,099.76 mg/kg), Mg (1,311.01-1,865.65 mg/kg), Fe (29.23-40.98 mg/kg), Zn (24.14-35.68 mg/kg), Mn (8.56-14.01 mg/kg), and Cu (7.72-14.20 mg/kg). The germplasm from the Asian region varied widely for grain nutrients, and the ones from African region had high nutrient density. The significant genotype x environment interaction for most of the grain nutrients (except for P, K, and Ca) indicated the sensitivity of nutrient accumulation to the environment. Days to 50% flowering and days to maturity had significant negative correlation with most of the grain nutrients, while grain yield per plant had significant positive correlation with protein and magnesium, which can benefit simultaneous improvement of agronomic traits with grain nutrients. Clustering of germplasms based on Ward.D2 clustering algorithm revealed the co-clustering of germplasm from different regions. The identified top 10 nutrient-specific and 15 multi-nutrient dense landraces can serve as promising sources for the development of biofortified lines in a superior agronomic background with a broad genetic base to fit the drylands. Furthermore, the large phenotypic data generated in this study can serve as a raw material for conducting SNP/haplotype-based GWAS to identify genetic variants that can accelerate genetic gains in grain nutrient improvement