Biochemical changes in pigeon-pea leaves infested with Alternaria tenuissima

Biological changes leaves in pigeon pea leave of three cultivars viz., DA-2(Resistant), Prabhat(Moderately resistant) and Bahar(Highly susceptible) infected with Alternaria tenuissima causing leaf blight were studied. The contents of polyphenol, total sugar, nitrogen, phosphorus and potash were recorded in healthy and diseased pigeon pea leaves. These varieties varied in respect of their contents. The total and reducing sugars were significantly more in healthy leaves of resistant variety DA-2. Nitrogen content was more in highly susceptible variety Bahar whereas phosphorus content was distinctly more in healthy leaves of resistant variety. Similarly, the leaves of resistant variety showed clearly higher potash content in healthy and diseased leaves than moderately resistant and highly susceptible varieties. Polyphenol content in healthy leaves was higher in resistant and moderately resistant varieties than susceptible ones. The content was significantly reduced due to disease occurrence. In variety DA-2 and Prabhat, reduction of polyphenol content was low due to disease infection. However, reduction percentage was more in susceptible variety Bahar.