Distribution of Oligaphorura ursi in Morchella Cultivation Soil, Screening of Pesticides, and Analysis of Their Effects on Mycelial Growth and Pesticide Residues

To identify the species of Collembola that harm Morchella and to screen for pesticides that are effective in controlling these pests with minimal inhibition of mycelial growth, a five-point sampling method was used to investigate the population of Collembola and its damaging effects on Morchella and to analyze its spatial distribution in the soil. The indoor control efficacy of ten insecticides was determined using the mushroom disc immersion method and the pesticide film method. The most effective insecticides were then selected for field testing. The effect of the best-performing field pesticides on the mycelial growth of Morchella was measured using the Petri dish mycelial growth rate method, and pesticide residues were detected using chromatography. The survey revealed that in three Morchella greenhouses, the average Collembola population was 220,333 individuals/m3. The spatial distribution of Collembola was uniform. The collected Collembola specimens were identified as Oligaphorura ursi from the family Onychiuridae. Through the lab and field screening of pesticides, it was found that 40% phoxim EC, 1.8% abamectin EC, 2.5% lambda-cyhalothrin EW, and 4.5% beta-cypermethrin EC had the best efficacy. Meanwhile, residues of these four pesticides were not detected. Mycelial growth inhibition experiments showed that 2.5% lambda-cyhalothrin EW, 1.8% abamectin EC, and 4.5% beta-cypermethrin EC exhibit low inhibition of mycelial growth and can be used as control pesticides for Collembola on Morchella, providing a technical reference for the green pesticide control of Collembola on Morchella in the study region.