PREVALENCE OF EARLY BLIGHT OF TOMATO AND DIFFERENCES AMONG ISOLATES OF ALTERNARIA SOLANI IN PESHAWAR DIVISION

摘要

A survey was conducted in Peshawar division to determine the incidence of early blight of tomato caused by Alternari asolani. High disease incidence (100%) was recorded in Pathwarbala, Sufaid sang, kanderysadin and Shahibala. Regiaftezai and Malakandhir had the lowest (50%) incidence of the disease. Alternaria solani was successfully isolated on PDA medium from the infected tomato leaves of three locations. Comparison of the isolates showed Regilalma isolate to be the most vigorous. The conidia of this isolate were found to be wider than those of the other isolates. All the three isolates grew better at pH 6.0 and 5.5 as compared to pH4.5. Regilalma and Nasir bagh isolates registered more abundant growth than the Malakandhir isolate. These result shows that isolates of Alternaria solani may differ in their growth and virulence over short distances.