The biochemical changes in cluster bean leaves due to Alternaria blight infection

Abstract

Cluster bean is being grown in India since ancient time. Although believed to be of African origin (Vavilov, 1951), it was domesticated centuries ago in the north-western region of the Indo Pakistan sub-continent (Hymowitz, 1972). Tender green guar pods are important source of nutrition to human being and animals. Alternaria blight is an important disease as it acts as one of the limiting factors in its production. The present investigations and studies were carried on variability of pathogen and its disease management. The biochemical data indicate that the content of protein, total soluble sugar, reducing sugar and chlorophyll in diseased leaf of different varieties gradually and significantly decreased as compared to healthy leaf of same variety. In contrast the total phenol and O-dihydroxy phenol content were significantly increased in diseased leaf samples with the progress of the disease as compared to healthy leaf samples. Protein, total sugar, reducing sugar and chlorophyll contents were decreased with the infection of pathogen in the diseased sample whereas the total phenol and O-dihydroxy phenol were increased with increasing the disease in the diseased leaf sample of different varieties.