Artificial culture, host infection and pycnidial development of Ascochyta sorghina Sacc

Abstract

Mode of penetration and subsequent development of Ascochyta sorghina Saccardo in the leaf tissues of sorghum (Sorghum vulgare Pers.) were studied under field conditions. Penetration by A. sorghina was observed both directly through the epidermis and indirectly through the stomatal openings in the leaves. The pathogen produced intercellular mycelium, which later became intracellular after death of cells around the infection site through action of toxic metabolites produced by the pathogen. The pycnidia developed through the growth of a subcuticular hyphal crust.