The Changes in Susceptibility Status of The Old and of The Newly Registered Chickpea (Cicer Arietinum L.) Cultivars With Respect to the Blight Disease Caused By the Pathotypes of Ascochyta Rabiei (Pass.) Lahr.

Abstract

Blight disease, caused by Ascochyta rabiei (Pass.) Labrousse (teleomorph=Didymella rabiei), is one of the most important biotic stress factors affecting chickpea produc-tion worldwide. The high variation in disease severity among different chickpea cul-tivars and the decrease in the resistance of the cultivars over time make it necessary to test the cultivars regularly. The aim in this research was to determine and evalu-ate the changes in the susceptibility of chickpea cultivars, which were developed in different years and widely cultivated, against A. rabiei pathotypes in Turkey. A three -replication pot experiment was conducted in a randomized plot design in the climate chamber in 2021. Fifteen registered chickpea cultivars (including one susceptible and one susceptible control cultivar) and four pathotypes of chickpea blight disease agent A. rabiei were used in the study. While Pathotype-IV was determined as the most aggressive, it was followed by the Pathotype-III, Pathotype-II, and Pathotype-I, respectively. The Azkan cultivar, included as a Tolerant (T) control in the experiment, had the Mid-Susceptible/Susceptible (MS/S) values, which can be explained by the decrease in resistance over time. However, it is opined that the main reason for the better resistance values of Akcin-91, registered in 1991, and Gokce, registered in 1997, was provoked by the genetic basis of these cultivars, when compared to the recently registered cultivars.