Distribution and frequency paraquat resistant populations of Eleusine indica on cornfield in Karo Regency

Abstract

Karo Regency as the largest corn production centre in North Sumatra Province is at risk of having a high frequency of paraquat-resistant populations of Eleusine indica, this is due to the continuous use of paraquat for a long time. This study aims to determine the distribution and frequency paraquat-resistant population of E. indica on cornfield in Karo Regency. Sampling was conducted in March - July 2019. Weed seed samples were taken from six Sub-districts that have the largest corn production in Karo Regency. Resistance tests were conducted in August - September 2019 at the weed resistance research laboratory in the Faculty of Agriculture, Universitas Sumatera Utara. Weed seeds from 72 suspected paraquat-resistant populations and 1 paraquat-sensitive population were planted each with 10 plants / pots and arranged using a Randomized Block Design in four replications. The paraquat dose used is the recommended dose of 600 g.b.a./ha. The application is carried out using an electric knapsack sprayer with teejetnozle and a spray volume of 320 L per hectare. The results of this study indicate that there are 70 populations (97.2%) of the paraquat-resistant category, 1 sample (1.4%) of the paraquat-resistant developing category and 1 population (1.4%) of the paraquat-sensitive category.