Fertility Restoration in Male Sterille ✕ Maintainer Hybrids of Pearl Millet
- K. N. Rai and
- C. T. Hash
Effects of environment and parental nuclear genotype may cause considerable difficulties in the identification of maintainer lines (Blines) and in the classification of different sources of cytoplasmic male-sterility (cms) in pearl millet [Pennisetum glaucum (L.) R. Br.]. We studied the pollen shedding pattern as a measure of fertility restoration in A ✕ B hybrids of pearl millet by crossing seven cytoplasmic male-sterile lines (A-lines) with the B-lines of each of the A-lines at the ICRISAT Center in the dry and rainy seasons for 2 yr. Five of the A, system A-lines (i.e. A ✕ B parental crosses) were stable for male-sterility, whereas one was sterile in the dry season but produced a low frequency of pollen shedders in the rainy season. The non-Al system A-line (PT 732A) produced a low frequency of pollen shedders in both dry and rainy seasons. In comparison, almost all the non parental A ✕ B hybrids were uniformly or predominantly fertile across all the tests. The seed set data under selfing were generally supportive of the pollen fertility pattern. These results indicate that isonuclear lines or hybrids should be used for the reliable classification of cms sources in pearl millet. Fertility restoration pattern of hybrids in our study does not provide adequate evidence for differentiating the cytoplasm of PT 732A from that of Tift 23A1. A higher proportion of B-lines produced sterile hybrids on 81A than on other A-lines, indicating that 81A is a more efficient tester than other A-lines used in this study for identifying B-line sources.
Copyright © . .