Screening of Kharif onion varieties against Pythium spp. and Alternaria porri

摘要

Onion (Allium cepa L.) is one of the commonly used vegetable cum spices in India. Around 34.93 lakh tonnes of onion were exported from India during the year 2016-17. Damping-off and purple blotch caused by Pythium spp. and Alternaria porri (Ellis) Cifare the widespread fungal diseases consequences yield loss ranging from 2.5 to 97 per cent in onion. Being an important export-oriented vegetable; the diseases reduce the economic yield of the crop. Keeping this in view, the present experiment was carried out to identify the resistant varieties of onion during the Kharif season. The field experiment was laid out in the randomized block design with nineteen onion varieties and replicated twice. Results from the experiment revealed that none of the evaluated genotypes were found under immune or resistant. However, Phule Samartha was moderately resistant and sixteen varieties viz. Bhima Raj, Bhima Red, Bhima Super, Bhima Dark Red, Bhima Subhra, Bhima Safeda, Arka Niketan, Arka Kalyan, Arka Pragati, N-2-4-1, Baswant-780, NHRDF Red (L-28), Agrifound Dark Red, Pusa White Flate, Pusa White Round and N-53 were under the category of moderately susceptible and two varieties viz. Sukha Sagar and Bhima Sweta were susceptible to fungal diseases like damping-off and purple blotch. The variety, namely Bhima Raj was found significantly superior with respect to yield.