Pearl millet (Pennisetum glaucum (L.) R. Br.) is an important cereal in semi-arid tropics in Africa and India. Conventionally, millet has good amounts of grain minerals compared to other cereals. Estimation of genetic parameters would be useful in developing appropriate breeding and selection strategies. The present study was conducted to evaluate the local pearl millet accessions to assess the magnitude of variability and to understand the heritable component of variation present in the yield and nutritional characters. A field trial was laid under the complete randomized block design (RCBD) with three replications; observation were recorded on eight morphological and seven nutritional characters (as detailed in material and methods) including anti-nutritional properties such as phytate content among 61 genotypes collected from millet collection. The phenotypic coefficient of variation (PCV) was greater than genotypic coefficient of variation (GCV) for all the characters studied; this shows the influence of environmental factors on the characters. The phosphorus content had expressed the highest phenotypic and genotypic variances (845.30 and 772.08, respectively). The magnitudes of phenotypic and genotypic variances were low for the 100 grain weight (0.001 for both phenotypic and genotypic variance). High estimates of genetic coefficient of variation, heritability and genetic advance were exhibited by iron and crude fat content. Heritability is a measure of possible genetic advancement under selection. High heritability was observed for all the traits under study except seed weight which had moderate heritability. High value of heritability coupled with high genetic advance as per cent of mean were recorded for number of productive tillers, crude protein, crude fat, phytate, phosphorus, calcium, iron and zinc content, indicating the important role of additive gene action for the expression of these characters. Therefore, selection based on these characters could bring about desired improvement in yield as well as nutritional quality of pearl millet cultivars.

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Exploitation of hybrid vigour is quite possible in cross-pollinated crops. However, pigeonpea is a grain legume crop with a moderate level of cross-pollination (20-70%), which is mainly aided by insect pollinators. As a first step, hybrids based on genetic male sterility (GMS) were developed in pigeonpea, but the hybrid seed production technique is not farmer-friendly, because in the hybrid seed production plot 50% of the population, which are male-fertile in the female rows, have to be eliminated in time before contamination. This requires skilled labour and is a time-consuming process, which increases the cost of hybrid seed production. Therefore, the objective of this study was to develop cytoplasmic-genetic male-sterile (CGMS) lines in pigeonpea through wide hybridization, which would be very suitable for hybrid seed production. Two CGMS lines, viz. CORG 990052 A and CORG 990047, were developed by interspecific hybridization of Cajanus cajan and C. scarabaeoides. Restorers were identified and three CGMS-based pigeonpea hybrids were developed. The hybrid COPH 3 is found to be promising in Tamil Nadu State, India.

Random amplified polymorphic DNA (RAPD) analysis was applied to pearl millet genotypes in order to assess the degree of polymorphisms within and among genotypes and to investigate if this approach was suitable for genetic studies of pearl millet. 20 genotypes were evaluated using 30 different 10-mer primers of arbitrary sequence. Most of the primers did not reveal any polymorphism; however 12 primers revealed scorable polymorphism between genotypes of pearl millet and these can be further evaluated for use in genetic mapping. Pair-wise comparisons of unique and shared polymorphic amplification products were generated by Jaccard's similarity co-efficient. These similarity co-efficients were employed to construct a dendrogram showing phylogenetic relationships using unweighted paired group method with arithmetic averages (UPGMA). The UPGMA analysis indicated a higher similarity between genotype PT 2835/1 and PT 5552 and lowest similarity index was observed between PT 5554 and PT 2835/1. Analysis of RAPD data appears to be helpful in determining the genetic relationship among 20 pearl millet genotypes. The associations among the 20 genotypes were also examined with Principle components analysis (PCA) from Jaccard's similarity co-efficient and it is more informative to analyze the extreme genotypes.

The range of variation for different characters indicated wide differences among the genotypes both in main and ratoon crop. The phenotypic and genotypic co-efficient of variation was high for stem girth, length of fourth internode, total soluble solids and green stalk yield in main crop. High heritability and high genetic advance as per cent of mean for plant height, stem girth, length of fourth internode, green stalk yield, juice yield and jaggery yield both in main and ratoon crop indicated the presence of additive genes for these characters. Non-additive gene action was predominant for number of internodes in both main and ratoon crop. Juice yield showed strong positive correlation with jaggery yield in both main and ratoon crops. The juice yield had high positive direct effect in both main and ratoon crops. Hence, selection for high juice yield might be effective in achieving higher jaggery yield in sweet sorghum.