Genetics of cytoplasmic-nuclear male sterility and identification of molecular markers of fertility restorer genes in pearl millet (pennisetum glaucum (l.) It. Br.)D VYadavauthorThe present investigation was undertaken to determine the inheritance of five diverse CMS systems (Al, Ad, AqP, As and A,), allelic relationship of fertility restorer genes in A1 and A4 CMS systems, genetic linkage between the fertility restorer genes of the Al and A4 CMS systems, and identification of molecular markers linked to fertility restoration of these two CMS systems in pearl millet. The plant material for the study consisted of isonuclear A-lines of the five diverse male-sterility-inducing cytoplasm in three diverse nuclear genetic backgrounds (SIB, 5054B and !CMB 88004) and six pollen parents restoring the male fertility of hybrids based on any one, two or three male-sterile cytoplasm. The segregation patterns of male-fertile (F) and male-sterile (S) plants were studied in Fz, BCI [A x (A x R)] and BC2 [R x (A x R)] populations produced from A r l< crosses. bzs produced from some of the (A x R) x (B x R) crosses. and testcrosses obtained by crossing A-lines with individual plants of (B x R)-derived F2 and BCI populations. The FI hybrids and BC2 populations produced from A x R crosses for all the five CMS systems had all plants hlly fertile across the two test environments of summer and rainy seasons, indicating that male-fertility is dominant over male-sterility. The segregation patterns for F and S plants observed in the F2 and BCI populations were tested for X' goodness of fit for monogenic, digenic and trigenic ratios to determine the number of genes involved in the fertility restoration of each of the five cytoplasmic-genic male-sterility (CMS) systems. A summary of the results obtained in segregating populations and testcrosses included in the present study conducted at 1C'RISAT-l'atanchcru is gikcn below.MilletsGenetics and GenomicsAgriculture-Farming, Production, Technology, Economics2005Chaudhary Charan Singh Haryana Agricultural University;Department of Plant BreedingThesis