In this study, the effects of organic silicon (Si) on the toxicity of imidacloprid to a new invasive mealybug, Phenacoccus solenopsis (Hemiptera: Pseudococcidae), infesting Portulaca grandiflora (Caryophyllales: Portulacaceae) plants were evaluated using spotting and dipping methods under laboratory and field conditions to improve management strategies for solenopsis mealybug. | Turkish Journal of Agriculture and Forestry Turk J Agric For (2014) 38: 207-213 © TÜBİTAK doi: Research Article Do organic silicon and imidacloprid synergistically induce toxicity to the new invasive mealybug Phenacoccus solenopsis Tinsley on Portulaca grandiflora plants? 1, 1 2 2 3 1 Jun HUANG * , Juan ZHANG , Daoze WANG , Lili ZHANG , Yijuan XU , Mingjiang LI Flower Research and Development Center, Zhejiang Academy of Agricultural Sciences, Xiaoshan, Hangzhou, . China 2 Plant Protection and Soil Fertilizer of Hangzhou General Station, Hangzhou, . China 3 Red Imported Fire Ant Research Center, South China Agricultural University, Guangzhou, . China 1 Received: Accepted: Published Online: Printed: Abstract: In this study, the effects of organic silicon (Si) on the toxicity of imidacloprid to a new invasive mealybug, Phenacoccus solenopsis (Hemiptera: Pseudococcidae), infesting Portulaca grandiflora (Caryophyllales: Portulacaceae) plants were evaluated using spotting and dipping methods under laboratory and field conditions to improve management strategies for solenopsis mealybug. Results showed significant synergistic effects of organic Si with imidacloprid solution against third-instar P. solenopsis nymphs and adult females. However, the percentage mortalities increased remarkably after P. solenopsis was exposed to 100, 50, and 25 mg of imidacloprid combined with organic Si. For the third-instar nymphs, these values increased to 100%, 100%, and , respectively; for the adult females, these values increased to 100%, 100%, and , respectively. After 5 days, the percentage mortalities reached , , and when the third-instar nymphs were exposed to 100, 50, and 25 mg of imidacloprid solution, respectively. The percentage mortalities reached , , and when adult females were exposed to
