Int.J.Curr.Microbiol.App.Sci (2018) 7(6): 1046-1053 1046 Original Research Article https://doi.org/10.20546/ijcmas.2018.706.124 Use of Non-Conventional Chemicals against Early Blight of Potato (Solanum tuberosum) Caused by Alternaria solani Dibakar Panda 1 , Ashish Chakraborty 2 , Ritesh Kumar 2* and Saurav Govind Rao 3 1 Department of Plant Protection, Palli Siksha Bhavana, Visva Bharati, West Bengal, India 2 Department of Plant Pathology, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal, India 3 Department of Plant Pathology, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur, Uttar Pradesh, India *Corresponding author ABSTRACT Introduction Potato (Solanum tuberosum L.) is an important food crop of the world. It is used as vegetable, stock feed and in industries for manufacturing starch, alcoholic beverages and other processed products. Potato is the world's fourth-largest food crop, after maize, wheat and rice. The crop is a native of South American continent from about 7000 to 9000 years ago. It was introduced in India by Portuguese during early 17 th century. It has the global production of 482 lakh tonnes (GoI). Alone, India is producing over 45 million tonnes of potatoes, sharing more than 12% of the global production at an average productivity of 23 tonnes per hectare (2013- 14) which is second only to China (Hussain, 2016). In India, the major Potato growing states are Uttar Pradesh, West Bengal, Bihar, Madhya Pradesh, Gujarat, Punjab, Assam, Haryana, Jharkhand, Chhattisgarh, Karnataka International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 7 Number 06 (2018) Journal homepage: http://www.ijcmas.com An experiment was conducted to find out efficacy of different non-conventional chemicals to manage the early blight disease in potato. Study was carried out with seven chemicals i.e. lithium sulphate, calcium chloride, oxalic acid, salicylic acid, iron sulphate, potassium bicarbonate and ascorbic acid in in vitro condition for their conidial germination efficacy against Alternaria solani. It was observed that, oxalic acid@ 1.0 ppm concentration exhibited highest per cent inhibition of conidial germination (88.89%) over control after 24 hrs. The next best conidial germination inhibition (75.00%) was observed in case of lithium sulphate@ 1ppm concentration. This was followed by potassium bicarbonate, where 71.43% conidial germination inhibition was observed @ 1 ppm concentration. In the field condition, also the oxalic acid @ 1 ml/ lit exhibited best result in terms of percent disease incidence (32.62%), percent disease intensity (24.32%) at 73 DAP and yield of tubers (25.31 t/ha) as compared to control treatment. The overall disease reduction in case of oxalic acid was 42.10% over control which was also highest compared to all other treatments. Keywords Alternaria solani, Early blight, Non- conventional Accepted: 06 May 2018 Available Online: 10 June 2018 Article Info