EFFECT OF CYTOPLASM ON COMBINING ABILITY AND DRY FODDER
YIELD CONTRIBUTING TRAITS IN PEARL MILLET [PENNISETUM GLAUCUM (L.) R. BR.]
R. KUMAR* AND P. SAGAR
Department of Plant Breeding
CCS Haryana Agricultural University,
Hisar-125 004 (Haryana), India
*(e-mail : rameshkrgr@gmail.com)
(Received : 15 January 2015; Accepted : 20 February 2015)
SUMMARY
The effect of cytoplasm on dry fodder yield and combining ability for dry fodder yield and its contributing traits was studied in 144 hybrids. Six male sterile (A) lines [81A and HMS 8A (A1), Pb3l3A (A2), Pb402A (A3), 81A4 and 81A5] representing five different cytoplasm systems and their corresponding maintainer (B) lines were crossed with 12 restorer (R) lines in a line x tester design. The 24 parents (A+B and R) and 144 crosses were grown separately in contiguous block in randomized block design with two replications in six environments, three each (El, E2 and E3) and (E4, E5 and E6) during two years. The data were reported for dry fodder yield (g/plant) and major dry fodder yield contributing characters–plant height (cm), total tillers at maturity and number of leaves per main tiller. Analysis of variance revealed significant differences among genotypes, parents, lines (A, B), testers and hybrids (A x R, B x R). The differences due to A vs. B were non- significant except for dry fodder yield (g/plant) and number of leaves per main tiller; and A x R vs. B x R crosses were significant except for number of leaves per main tiller. Cytoplasmic effects were estimated by comparing A x R and B x R hybrids combination. The results indicated that a few number of cytoplasmic effects was significant. Both positive and negative cytoplasmic effects were observed for three characters viz., dry fodder yield (g/plant), plant height (cm) and total tillers at maturity. The (A x R vs. B x R) x E component of variance exhibited significance for all the characters except for number of leaves per main tiller. The effects were modified by environment and were more pronounced for dry fodder yield, plant height and total tillers and negative cytoplasmic effects exceeded than the positive ones. The negative cytoplasmic effects were preponderant for dry fodder yield and significant only in one environment which was due to cytoplasm and nuclear-genome interaction. Effect of cytoplasm was more or less equally pronounced on general combining ability effects of parents and specific combining ability of crosses. The effect of cytoplasm on general combining ability both positive and negative was highest for lines HMS 8A1, 81A1, Pb402A3 and 81A5. Array mean performance of 81A cytoplasmic iso-hybrids indicated that all the three cytoplasms had same potential; therefore, any of these cytoplasms can be used in hybrid breeding.
Key words: Pearl millet, cytoplasmic effects, combining ability