Effect of greenhouse on the occurrence. and damage caused by, Drosophila suzukii Matsumura in bayberry orchards

Author of the article:LI Ru-Yi1** XIONG Yan1** LI Cheng-Yun1 LI Ming-Yue1 HU Chun-Hua1 LI Hong-Yan2 JIANG Shao-Kun2

Author's Workplace：1. Yunnan Agricultural University, Kunming 650201, China; 2. Agricultural and Science-Technology Bureau of Shiping County, Shiping 662200, China

Key Words：Drosophila suzukii, bayberry orchard, greenhouse, occurrence, damage

Abstract：[Objectives]  To evaluate whether greenhouses can reduce the damage caused by the spotted wing Drosophila (SWD), Drosophila suzukii, to bayberry, Myrica rubra, crops. [Methods]  Greenhouses were built in bayberry orchards one month before the fruit ripened. Adults were trapped using a sweet lure (sugar + vinegar + alcohol + water) to investigate population dynamics and their daily activity patterns both inside and outside greenhouses. Fresh and fallen fruits were collected regularly both inside and outside greenhouses and taken to a laboratory for further examination. Some fruits were immersed in salty water (5%) to determine the Drosophila (including D. suzukii, D. melanogaster and the other Drosophila species) infestation rate and others were kept in the laboratory until insects emerged to determine the D. suzukii infestation rate. [Results]  There was no significant difference in the infestation rate, or population dynamics, inside and outside greenhouses before fruits ripened but the infestation rate of fruits inside greenhouses was significantly lower than that outside as fruits began to ripen. Field observations showed that activity peaks of D. suzukii both inside and outside greenhouses were in the early morning (7:00-9:00) and late evening (17:00-19:00). [Conclusion]  Growing bayberry in greenhouses can reduce the damage caused by SWD to bayberry fruits.