Int.J.Curr.Microbiol.App.Sci (2019) 8(11): 908-919 908 Original Research Article https://doi.org/10.20546/ijcmas.2019.811.106 In Vitro Evaluation of Fungicides against Aspergillus niger causing Collar Rot Disease in Groundnut (Arachis hypogaea L.) Amritpal Singh Sekhon*, Prabhjodh Singh Sandhu, Pankaj Sharma and Rakesh Belludi Department of Plant Pathology, Punjab Agricultural University, Ludhiana, 141004, Punjab, India *Corresponding author ABSTRACT Introduction Groundnut (Arachis hypogaea L.) is an important oilseeds and ancillary food crop in India with 7.4 million tonnes production from 4.7 million ha area and also has good export potential. India is the largest grower and second largest producer of groundnut after China with a national average productivity of about 1552 kg/ha (Anonymous, 2015). Major groundnut growing states in India are Gujarat, Andhra Pradesh, Tamil Nadu, Karnataka, Rajasthan and Punjab. The productivity of groundnut in India is low in comparison to world average may be due to the damage caused by diseases and insect pests. Diseases cause considerable yield losses in groundnut. Fungal, virus and bacterial pathogens attack International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 8 Number 11 (2019) Journal homepage: http://www.ijcmas.com The present study was carried out to evaluate the efficacy of six fungicides against Aspergillus niger using two in vitro methods namely poisoned food technique and paper towel method. Poisoned food technique was carried out by making potato dextrose agar medium poisoned with different concentrations of fungicides followed by inoculation with actively growing culture of A. niger. Among the fungicides tested by using above method, tebuconazole at concentrations of 25, 50, 100 and 200 ppm and azoxystrobin at concentrations of 100 and 200 ppm, completely (100%) inhibited the mycelial growth of A. niger followed by carbendazim 25% + mancozeb 50% (Sprint) @ 200 ppm (94.38%). In paper towel method, two varieties of groundnut namely SG-99 and M-522 were tested. In this method, seeds from previously collar rot infected plants were taken and treated with fungicides, then wrapped between two paper towels and these were kept in incubator. The minimum seed per cent mortality and seed rots due to A. niger was observed in seed treatment with tebuconazole followed by azoxystrobin and carbendazim 25% + mancozeb 50% (Sprint) in both of the tested varieties. In both methods, three fungicides namely tebuconazole, azoxystrobin and carbendazim 25% + mancozeb 50% (Sprint) found most effective against A. niger. Keywords Aspergillus niger, Fungicides, Groundnut, Collar rot, Potato dextrose agar medium Accepted: 10 October 2019 Available Online: 10 November 2019 Article Info