ប្រសិទ្ធិភាពនៃថ្នាំកម្ចាត់ដង្កូវមូរស្លឹក (Cnaphalocrocis medinalis Guenee) លើដំណាំស្រូវនៅសង្កាត់ទឹកថ្លា ក្រុងសិរីសោភ័ណ ខេត្តបន្ទាយមានជ័យ

Abstract

Rice leaf folders are the major insect pests of rice crops. Insecticides are used by farmers to reduce the yield loss caused by rice leaf folders, but there are hundreds of insecticides available on the Cambodian market, which makes choosing the right insecticide difficult. This experiment was conducted (1) to determine the variation of a population of rice leaf folders in six treatments: control and using insecticide treatments, and (2) to determine the type of insecticide that is effective. The treatments were tested on field plots (5m x 4m). There are six treatments, and each treatment was replicated three times in a Randomized Complete Block Design. The treatments were T0 = Control, T1 = Emamictin-benzoate 50WDG, T2 = Cypermethrin 10EC, T3 = Thiacloprid + Isoprocarb 450WP, T4 = Diazinon 50EC, and T5 = Thiamethoxam 350SC. The data was collected by counting the number of rice folder larval populations from 100 hills of rice which is equal to one square meter before and after applying the insecticides. The rice yield per square meter in each plot was also collected. The results showed that the rice leaf folder had severe damage in the tillering stage (about 14 days after transplanting). The most effective insecticide in killing rice leaf folders was Emamictin-benzoate 50WDG (T1) at 87.68%, followed by Diazinon 50EC (T4) at 83.04% and Cypermethrin 10EC (T2) at 81.51%. There was a significant difference if compared with Thiamethoxam 350SC (T5) and Thiacloprid + Isoprocarb 450WP (T3) at 80.95% (p <0.05). As a result, we can conclude that Emamictin-benzoate 50WDG is highly effective and yields the highest yield when used to control rice leaf folders.