The occurrence of genetic male sterility and development of highly sterile lines have been reported. The male sterility was not accompanied by any visible chromosomal aberration. It behaved as recessive and was governed by multiple factors. It was hypothesised that three major genes with additive effect were operating to produce highly sterile forms while less sterile forms would be dependent on one or two genes. The expression of male sterility was also influenced by modifying factors and environments.

Combining ability studies with respect to grain quality characteristics viz., beta-Carotene, total carotenoids, protein content, 250-grain weight, grain hardness and grain yield were carried out from a 13x13 diallel cross set in pearl millet [Pennisetum typhoides (Burm S&H)].The parents versus hybrids comparison indicated significant heterosis for all the traits under study. In general the hybrids having higher grain yield had bold hard grains with more carotene but low protein content, although a few hybrids combined high yield with an average protein percentage. The relative proportions of the general and specific combining ability variances indicated predominance of non-additive genetic variance with respect to all the traits. The per se performance of parents provided a fairly good indication of their combining ability in most cases. Parents possessing desirable grain quality characteristics were identified. Breeding implications are discussed.

The objectives of the study were to estimate the genetie eomponents of varianee, prediet the response to selection and to evaluate observed response to selection using two populations namely, PSB 7 and PSB 3, of pearl millet (Pennisetum americanum [L.] Leeks). The observed response was studied using four methods of seleetion based on single and multitrait eriteria in three types of families, namely SI, half-sib (HS) and full-sib (FS) families. One hundred SI, HS and I'S families eaeh were developed in PSB 7 and PSB 3. Plants within a population were pollinated with bulk pollen of other population to develop HS famihes. Grosses were made between a pair of plants using one plant from eaeh of the two populations to develop FS famihes. Data were recorded on days to flower, plant height, tiller number, spike length, spike girth, seed yield per plant and spike weight. Additive genetie varianee estimates were significant for all traits. The estimates of dominanee and additive X location and dominanee X loeation interaetion components were not significant, except additive X loeation component in PSB 7 for seed yield and spike weight. The genotypie eomponent of varianee among SI families and SI X location interactions were signifieant exeept SI X location interactions in PSB 7 for days to flower, spike length and spike girth.Twenty-four strains were developed by lntermating superior families identified on the basis of four selection methods in eaeh of the six types of families.A part of a thesis submitted by the senior author in partial fulfilment of the requirements for a Ph. D. degreeThe seleetion methods were high seed yield (YS) per se; index seleetion (IS) for high tiller number and long and thiek spike; truncation seleetion (TS) for high yield among the families having days to flower and plant height lower than the population mean; and visual seleetion (VS) after eompletion of flowering for good vigour, uniformity in plant height and good infloreseenee attributes. YS and IS were found to be superior to TS and VS with respect to observed genetie gains for seed yield. That advance was higher in seleetion among SI families as compared with FS and HS families. In general, a good agreement was noted between observed and expected responses. Expected genetie gain from FS reciprocal (R) recurrent seleetion was higher than the average gain from HS-R selection.

Genetic and cytoplasmic effects on chlorophyll content in pearl millet were studied using a complete 10-parent diallel cross under two dates of sowing. Chlorophyll a, chlorophyll b and chlorophyll a + b were not affected by the sowing dates. The estimation of components of genetic variance indicated a predominantly non-additive gene action in the inheritance of chlorophylls. Reciprocal cross differences and maternal effects were pronounced in several cross combinations.

A comparative study of peroxidase and acid phosphatase of anthers was carried out on sorghum to characterize five male steriles and their maintainers. Differences in presence/absence and intensity of bands were obsen.'ed for the isozyme patterns of all the male steriles and their corresponding maintainers. The better expression of enzymes in sterile anthers emphasized the role they play in breaking down various metabolites that are otherwise important for formation of fertile anthers.