Combining ability for seedling heat tolerance in pearl millet [Pennisetum glaucum (L.) R. Sr.]

Abstract

Poor establishment of plants in pearl millet [Pennisetum glaucum (L.) R. Br.] resulting in a reduction in grain yield has been frequently observed under high soil temperature and moisture stress conditions during seedling stage [1]. Breeding varieties with seedling heat tolerance is the most effective way to overcome the problem of poor crop establishment due to high soil temperature. Experimental material of this study consisted of eight inbred parents (HMS 1B, HMS 3B, RIB 335/74, 023, 20-K86, FTR 250-2-1, FTR285 and FTR 336) possessing different degree of tolerance to high temperature with diverse origins. The crosses were made in a diallel fashion excluding reciprocals. The resultant 28 hybrids and 8 parents (selfed) were raised in three replicated randomized block design during summer season of 1994 at the Agricultural Research Station, Fatehpur-Shekhawati. Each entry was grown in 2.5 m long single row, with 30 cm space between rows. On the night before sowing, 15 mm of water was applied uniformly to all plots from two parellel sprinkler lines spaced 12 m apart. The rows were opened on the day of sowing to a depth of 50 mm with the sharp edge of a metal rake, 80 seeds were immediately sown by hand and the soil replaced and compacted lightly with the flat edge of a rake to ensure good soil-seed contact. A field technique described by Peacock et al. [1] to screen pearl millet genotypes for seedling heat tolerance has been used in this stUdy.