PHYSIOLOGICAL AND MORPHOLOGICAL FEATURES DETERMINING THE PERFORMANCE OF THE SORGHUM LANDRACES OF NORTHERN NIGERIA

Sorghum landraces from contrasting districts of northern Nigeria were grown during the 1990 rainy season to describe their physiological and morphological features. Changes in their dry matter production and yi eld could be predicted from thermal time to flowering (based on respon se to a fixed daylength) and partitioning indices. Many other morpholo gical and physiological features, such as light-extinction coefficient , light-use efficiency, plant height, lear area and leaf number, were either stable or varied systematically with time to flowering. Grain y ields of early maturing lines were limited by low light interception f rom flowering to physiological maturity and those of later maturing li nes by highly site-specific drought stress.