Field Screening of Mungbean Genotypes and the Role of Total Soluble Sugars and Phenols against Powdery Mildew Resistance

Powdery mildew of mungbean caused by Erysiphe polygoni DC may cause yield loss up to 20–40%. Mungbean (51) genotypes were screened in three consecutive seasons under natural epiphytotic conditions. Out of 51 genotypes, TM-96-2 exhibited highly resistance, nine as resistance, five as moderately resistance, 16 as susceptible and 20 as highly susceptible reactions for powdery mildew. On the basis of field screening, two resistant and 10 susceptible genotypes were selected for the study of relationship between induced resistance mechanism with total soluble sugars and phenol contents in plants. The resistant genotypes contained high level of phenols than the susceptible genotypes while, susceptible genotypes contained high level of total soluble sugars than the resistant genotypes.