Suitability And COI Gene Polymorphism Analysis Of Phenacoccus Solenopsis

Phenacoccus Solenopsis is an important invasive pest which has seriously threat to agriculture of our country in recent years. Phenacoccus Solenopsis originated in North American, since it was introduced into China in 2008, it has spread to Guangdong and other nine provinces, which has a great proliferation risk and potential enormous harm. Phenacoccus Solenopsis has the characteristic of strong reproductive capacity, rapid diffusion and hazardous characteristics, which can caused potentially huge threat to China’s cotton industry. In order to grasp the possibility of an outbreak of the pest in our country, we should do inspection and quarantine work timely and accurately, do prevention and control work effectively. In this study, we study on the suitbility of Phenacoccus Solenopsis in China and COI gene polymorphism analysis. We use BIOCLIM model to analyze the suitable area of Phenacoccus Solenopsis in our country. The mt COI of Phenacoccus Solenopsis which have been found in Hainan, Guangdong, Guangxi, Yunnan, Jiangxi, Hunan, Zhejiang and Hubei were sequenced. We constructed the phylogenetic trees, and contrast the genetic distance of each geography populations. In this way, we can establish the effectively molecular detection system of Phenacoccus Solenopsis, to provide technical support for accurate molecular identification in quarantine work. We determined five kinds of chemical and microbial pesticides on cotton hibiscus mealybug virulence, provide a reference for Phenacoccus Solenopsis chemical control. The main findings are as follows:1. In this study, we use the BIOCLIM model to analyze the suitable areas of Phenacoccus Solenopsis in our country and the distribution possibility of each place is also evaluated. The results showed that P. solenopsis had a wide range of potential distribution in China. The high potential distribution area was the vast area in south of the Yellow River, including South China, Central China and North China. The medium and low potential distribution area were part of some provinces including Hebei, Liaoning, Shanxi, Inner Mongolia, Ningxia, Gansu, Xinjiang and Tibet. These potential distribution areas established three major cotton producing areas in China. The middle and lower reaches of Yangtze River cotton producing area and the middle and lower reaches of the Yellow River cotton producing area were the high potential distribution area, the northwest cotton producing area was the low potential distribution area.2. In this study, the mt COI of Phenacoccus Solenopsis which have been found in Hainan, Guangdong, Guangxi, Yunnan, Jiangxi, Hunan, Zhejiang and Hubei were sequenced. We landed in Gene Bank to contrast sequences, constructed the phylogenetic trees, and contrast the genetic distance of each geography populations.In this way, we can establish the effectively molecular detection system of Phenacoccus Solenopsis, to provide technical support for accurate molecular identification in quarantine work. In this study, by study on genetic differentiation of Phenacoccus Solenopsis populations, the results show that the identity of Phenacoccus Solenopsis COI sequences is high. The interspecific differentiation has not appeared. Phenacoccus Solenopsis which invaded in China belong to the same genetic clades with the pest from India and Pakistan, but the relations between Florida is far. Due to the time of introduction is short, in the mitochondrial genome level only a small amount of bases variation of Phenacoccus Solenopsis from different regions of China. The genetic differentiation has not appeared.3. We determined the virulence of five insecticides to Phenacoccus Solenopsis by bioassay, the results showed that after 48 h, the lethal bioassay LC50 of imidacloprid, acetamiprid, chlorpyrifos, nitenpyram, avermectin used with third-instar of Phenacoccus Solenopsis were 0.83,1.45,55.11,6.62 and 2.05 ppm. In this way, we can explain that the five agents of Phenacoccus Solenopsis prevention effects are good, all of them can be used in chemical control of Phenacoccus Solenopsis. Among these five insecticides, avermectin can be the best choice in chemical control of Phenacoccus Solenopsis.