Studies on Antifungal Effect of Some Essential Oils and Seed Dressing Fungicides Against Fusarium Sambucinum Causing Dry Rot of Potato

Abstract

Potato (Solanum tuberosum L.) is one of the most important food and cash crop grown worldwide. The center of origin is south America (Peru). It is belonged to Solanaeace family. Potato is consumed as staple food in more than forty countries in the world and rank fourth amongst all food crops. Potatoes are rich sources of starch, vitamins, especially C and B1 and minerals and contain 20.6% carbohydrates, 2.1% protein, 0.3% fat, 1.1% crude fiber and 0.9% ash. Being the second largest producer. India produced 45.34 million tons potato (12.32 % of world production) followed by 95.99 million tons China (24.17% of world production) and Russian federation produced 30.20 million ton (8.20% of world production). Hence nearly 45% of global potato production place in these three largest potatoes producing countries. In India the major Rabi Potato producing states are Uttar Pradesh, West Bengal, Bihar, Gujarat, Madhya Pradesh, Punjab, Assam, Chhattisgarh, Jharkhand and Haryana. All India production of Potato in 2019-20 is estimated to be 508.57 lakh tons. Potato in infected by a number of soil and tuber borne diseases and pest. Among all, dry rot (Fusarium sambucinum) is destructive disease of potato. The most common symptoms were appearing wrinkled skin developed white tuffs or pustules of the fungus, turning pink on posture to light. The tubers, when cut exposed, cavities in internal sues found filled with mycelium of the pathogen which considerably reduces market value of edible tuber. In present investigation different plant leaf essential oils and fungicides was tested management of disease in-vitro, pot and storage condition. An experiment was conduct for the efficacy of two plant leaf essential oil Cymbopogon citratus and citrus limon at 250, 500, 750, 1000 ppm concentration. And two fungicides Carbendazim and Azoxystrobin at 50, 150, 250 ppm concentration against Fusarium sambucinum. 100% inhibition of mycelium growth of pathogen was recorded in Cymbopogon citratus and citrus limon essential oil at 1000 ppm concentration at 144 hrs. of incubation at 26±2℃. In fungicide, 100% inhibition of mycelial growth was recorded in Carbendazim at 50, 150, 250 ppm followed by 87.27 % inhibition of mycelial growth was recorded in Azoxystrobin at 250ppm. A combination of practices such as seed treatments with essential oils, fungicides and addition of organic amendments for management of dry rot under pot condition. The minimum percent disease incidence 15.87% was recorded in potato tuber treatment with Carbendazim 50%WP @ 250 ppm and maximum percent disease incidence was recorded in 42.31% Potato tuber treatment with Cymbopogon citratus leaf essential oil @ 1000 ppm and soil Application with vermicompost @ 100g/kg soil in pot condition. An experiment was also conducted for management of dry rot of potato under storage condition. The lowest percent disease incidence was recorded in 11.1 % in Potato tuber treatment with Carbendazim 50%WP @ 250 ppm and the maximum percent disease incidence recorded in 37.78% Potato tuber treatment with Citrus limon leaf essential oil @ 250 ppm in storage