Genetic diversification of landrace-based populations of pearl millet (Pennisetum glaucum L. R. Br.) to enhance productivity and adaptation to arid zone environments

Abstract

In the present investigation, 20 crosses of pearl millet (Pennisetum glaucum L. R. Br.) and their nine parental combinations consisting of four landrace-based and five elite exotic populations were evaluated in four contrasting seasons within arid ecosystem in order to study their response pattern to a wide range of environmental conditions. In most severe drought year, the landrace-based populations outyielded other two groups by a margin of 33-72%. In favourable conditions, exotic elite populations provided significantly higher grain yield than landraces with average degree of superiority being 25-45% across two seasons. The hybridization between landrace-based and elite populations resulted into enhanced adaptation range of crosses, beyond that of their parents. Individual landraces and elite populations differed significantly in their general combining ability (gca) effects though landraces had, in general, more pronounced gcaeffects than elite populations. Landrace Jakharana and elite population ESRC provided their crosses both adaptation to stress conditions and also higher potential productivity. On the contrary, BarPop was established as an appropriate parent for producing cultivars with general adaptation giving high stover yield but with a significant penalty for grain yield. ERajPop appeared more suitable for producing grain type materials while WRajPop emerged suitable to produce dual-purpose materials. The elite populations MC and EC had effects for specific adaptation to drought conditions for grain yield productivity. The popUlations BSEC established as promising parent for grain yield but not for stover yield across environments. Results demonstrated that there are exploitable differences among landraces and elite populations for their ability to produce genetic material with a variety of combinations for grain and stover productivity and with differential adaptation pattern. Implication of these findings in pearl millet breeding for arid zone conditions is discussed.