Integrating Cultivar Resistance with a Single Fungicide Spray to Manage Ascochyta Blight for Increased Chickpea Yields

摘要

Field trials were conducted at 3 Mediterranean environments in Syria, during the cropping seasons of 1997 and 1998, to evaluate the control of chickpea Ascochyta blight with a single fungicide spray on 4 chickpea genotypes. Ascochyta blight disease epidemics were produced at the different locations and plots with the spread of Ascochyta-infected chickpea debris soon after crop germination. The plots were sprayed with a single application of the fungicide, Chlorothalonil at 4 different growth stages, starting from seedling stage to podding growth stage, to determine the effect of the fungicide application timing on Ascochyta blight severity, chickpea grain yield and grain quality. Generally, single applications made before flowering significantly (p<0.05) reduced disease severity in the 2 susceptible genotypes, Ghab1 and Ghab 3. Plot yields of these genotypes were also significantly greater than the untreated controls when applications were made at seedling or vegetative growth stages. There was no significant difference in disease severity and grain yield , between the untreated control and time of application on the resistant genotypes, F 90-96 and F 85-88. The timing of application had a significant effect on pod infection but generally no effect on seed weight. There were no significant effects of seed infection by Ascochyta rabiei . The results suggest that single fungicide sprays made before flowering are most effective in Ascochyta blight control under Mediterranean conditions and can also result in higher grain yield s than applications made at the reproductive phase of the crop.