Effect of yield potential, drought escape and drought tolerance on yield of pearl millet (Pennisetum glaucum) in different stress environments

Abstract

An experiment was conducted during the rainy season of 1988 and 1989 and the dry season of 1989 and 1990 to study the effectof yield potential, drought escape and tolerance on the grain yield of pearl millet [Pennisetum glaucum (L.) R. Br. emend.Stuntz] under stress. Different types of drought and heat stress occurred, viz moderate and severe post-flowering drought andsevcrepre-flowecing drought, combined with either high or low temperature during grain filling. Yield potential was onlyrelated to yield under stress when pre-flowering drought was combined with low temperatures. Escape was the predominantfactor if temperature was high, except if combined with pre-flowering drought, in which case tolerance became more important.These results show that for stressed environments, selection for yield potential is of limited use. The importance of escapeand tolerance, however, depends on the timing and intensity of stress occurrence. If pearl millet-growing regions can becharaoterized based on occurrence of abiotic stress, breeders can select more efficiently for plant traits that enhancestress adaptation in specific target environments.