Association of photosynthesis of flag leaves with grain yield in pearl millet (Pennisetumglaucum (L.) R. Br.)

Abstract

The grain yield of pearl millet has increased continuously in past decades through development of hybrids and improved production practices. Elite inbred lines are crucial for innovating new germplasm/traits to break the yield plateau. Hence, 64 inbred lines of pearl millet were evaluated to assess the extent of genetic variability and association among agronomic, physiological and grain yield contributing traits. Analysis of variance showed significant differences among the lines for all the traits indicating sufficient variability for genetic exploitation. The preferred arid adaptation traits, early flowering and high tillering were associated with each other making them amenable for simultaneous selection and these two traits were not associated with grain yield. Hence, for deriving ideotypes suitable for arid adaptation, intensive selection for grain yield in early flowering background was suggested. In productive regions, the plants having greater plant height, larger size of leaves including flag leaf, larger panicle size to accommodate the photosynthates are desirable and these traits were found to be associated among themselves and with grain yield in the current study. Though the maximal photosynthetic efficiency, Fv/Fm was significantly associated with leaf length, flag leaf length, flag leaf width and actual PSII efficiency (Y(II)), these physiological parameters did not significantly associate with grain yield directly and their effects are confounded within the leaf morphological variation.