Management of Ascochyta blight (Ascochyta rabiei (Pass.) Lab.) Disease of Chickpea (Cicer ariatinum L.)

Abstract

Ascochyta blight, caused by the fungus Ascochyta rabiei (recently renamed Phoma rabiei), is a serious disease of chickpeas in world. The fungus can infect all above ground parts of the plant and is most prevalent in areas where cool, cloudy and humid weather occurs during the crop season and attacks the crop at both vegetative and podding stages. Extremely wet conditions favoured disease development and spread. Management strategies are aimed at preventing the occurrence of disease and limiting its spread. Despite extensive pathological and molecular studies, the nature and extent of pathogenic variability in A. rabiei have not been clearly established. Several isolates of A. rabiei were grown in liquid culture medium which secreted phytotoxic compounds of solanapyrone A, B, C and cytochalasin D. The same fungal metabolites were also recovered from extract of naturally blight stricken chickpea plants. Seed treatment and foliar application of fungicides are commonly recommended for disease management, but further information on biology and survival of A. rabiei is needed to devise more effective management strategies. The inheritance studies have indicated involvement of more than one gene in controlling resistance to ascochyta blight. Involvement of two major complementary recessive genes in controlling resistance to ascochyta blight has been reported. A short description of chickpea blight, geographical distribution, disease cycle, symptoms, losses, production of phytotoxins and disease management practices for the control of Ascochyta blight will be discussed in this review article.