Ascochyta blight of chickpea: present status and future priorities

Ascochyta blight (Didymella rabiei (Kovach.) v. Arx) is an important disease of chickpea (Cicer arietinum L.) in most of the chickpea-growing countries of South Asia, the Middle East, the Mediterranean region and North Africa. It is especially important in countries that have adopted the winter-sown chickpea technology, where winter conditions that favour the growth of the crop are also ideal for the development of disease epidemics. Research has been carried out on the disease and the pathogen since it was first described on chickpea in 1911. These studies have centred on the pathogen, its biology, survival, spread and control. There are indications that the teleomorph of the pathogen may be playing a role in its variability and long distance spread. There are conflicting reports on the role of infected seed and debris in the survival and spread of the pathogen. Studies on strategies for control have focused largely on host resistance, but durable sources of resistance have not so far been identified. Emphasis is being shifted to integrated management of the disease. Despite the volume of research on ascochyta blight, some gaps still exist in our knowledge of the disease, especially in the areas of its spread, regional distribution and importance, epidemiology, mechanisms of pathogenic variability and genetics of host plant resistance.