Varietal Screening and Management of Basal Rot Disease of Onion

Onion (Allium cepa L.) belongs to the family Amaryllidaceae. It is known as common onion, bulb onion or biennial herb, and is one of the most important vegetable crops in India. However, the crop faces numerous diseases attack, resulting in losses to both quantity and quality. Among the diseases, the basal rot caused by Fusarium oxysporum f. sp. cepae, is one of the most significant soil-borne diseases. This work aimed to screen various onion varieties for resistance against basal rot in pots under glasshouse condition as well as to assess the efficacy of fungicides against the pathogen under both in vitro and in vivo conditions. It was observed that all onion varieties screened were highly susceptible while Bhima red was just susceptible; none of the varieties were resistant to basal rot. Under in vitro conditions the Fungicides Carbendazim and Tebuconazole, of the given concentration, were cent per cent effective in inhibiting mycelial growth of Fusarium oxysporum f. sp. cepae. For the field condition, the module of [carbendazim (2 g/kg) followed by tebuconazole (0.1 %) followed by azoxystrobin (0.1 %)] was the most effective.