Oral Acute Toxicity of Chemical Compounds used for Flower/fruit Thinner of Aapple against Buff-tailed Bumblebee, Bombus terrestris (Hymenoptera: Apidae)
2013
Kim, D.W., Andong National University, Andong, Republic of Korea | Jung, C.U., Andong National University, Andong, Republic of Korea
Pollination is the important process for fruiting. However too much fruit bearing results in lower quality fruit production. Thus the flower and fruit thinning is crucial and use of the chemical agents are increasing because the flower and fruit thinning is laborious and costly. At the same time, use of commercially produced buff-tailed bumblebee, Bombus terrestris in apple is increasing. We tested the feeding acute toxicity of potential chemical flower/fruit thinning agents (Lime sulfur, ATS, Carbaryl, NAD, NAA, BA) against the bumblebees. When treated with the recommended concentration of 2ml 50% sugar solution, carbaryl and lime sulfur showed 60% and 76% mortality respectively, while no mortality was observed in ATS, NAA, BA and NAD treatment. LC50 values for carbaryl and lime sulfur were 543 and 1631ppm 48 HAT. In feeding amount assay, sugar solution mixed with lime sulfur was least fed (52% of the control) followed by ATS (75%) and carbaryl (77%). LD50 values for carbaryl was estimated as 0.37ug a.i./bee and for lime sulfur as 2.74ug a.i./bee. Further experiments on contact and residual toxicity, and larger scale field study could contribute to the development of safe flower/fruit thinning chemical agents and pollinator protection program.
显示更多 [+] 显示较少 [-]