EFFECTS OF HIGH SOIL SURFACE-TEMPERATURE ON SEEDLING SURVIVAL IN PEARL-MILLET

A field technique to screen pearl millet genotypes for their emergence and survival at high soil surface temperatures is described. Genetic variation in seedling emergence and survival is shown and it is argued that this variation is largely due to tolerance of high temperatures rather than tolerance of soil moisture deficit, although some interact ion occurred. An index for 'thermotolerance' is defined and genotypes are ranked accordingly for this trait, which is shown to be highly her itable. The technique is repeatable and allows a large number of genot ypes to be screened at the same time.