The Regularity And Prevention Of Geisha Distinctis On Photinia Fraseri

At present, photinia fraseri is an important tree species for landscaping and afforestation; with its wide application, plant disease and insect pest control have been a vital part of its plantation and cultivation. As one of the major insect pests that endanger photinia fraseri, Geisha distinctissima has been paid much attention, in domestic and international researches, in terms of its classification, population, and harms and control as for economic tree species, such as tea plant, etc.; however, there have been scarce reports on its herms and control to photinia fraseri and other main greening tree species. To obtain a systematic understanding and a good mastering of the main biological habits of Geisha distinctissima in the island region of Zhoushan, and provide references for the control of its harms to photinia fraseri, the present study investigated the occurrence regularity of Geisha distinctissima in photinia fraseri in the island region of Zhoushan, and conducted pharmaceutical control experiments on Geisha distinctissima by using 40% methidathion EC, 75% dichlorvos EC, 20% fenvalerate EC and 10% imidacloprid WP. The primary outcomes are as follows:(1)Geisha distinctissima produces a generation per year in the island region of Zhoushan, with eggs overwintering inside the shoots of photinia fraseri, nymphs beginning to hatch in early May, incubating boomingly from middle May to late May, imagoes originating in middle June, and booming from late June to late July, which lasts until late October or early November.(2) There are 4 main ways in which Geisha distinctissima endangers the photinia fraseri: firstly, nymphs and imagoes of Geisha distinctissima pierce-suck the young shoots; secondly, imagoes lay eggs on the shoots, forming a longitudinal notch, subsequently resulting in a decreased sprouting rate in the new shoots the nest year; thirdly, nymphs and imagoes excrete honeydew, attracting aphids, ants, etc., consequently leading to sooty blotch, etc.; fourthly, nymphs leave a large amount of residual white wax floc on the branches when crawling, which has an influence on the photosynthesis of plants and the landscape effect.(3) Outcomes of the field control experiment demonstrated that the correction control effects of the 4 types of pesticides on the 3rd, 7th, 10 th and 15 th day were: 40% methidathion EC, 85.1%, 96.4%, 97.5%, 93.9%; 75% dichlorvos EC, 89.8%, 100%, 96.1%, 93.8%; 10% imidacloprid WP, 80.3%, 82.1%, 84.4%, 79.8%; 20% fenvalerate EC, 86.1%, 94.6%, 96.8%, 94.7%, respectively, indicating that the control effects of 4 types of pesticides followed an order of methidathion EC > fenvalerate EC > dichlorvos EC > imidacloprid WP.(4) From a comprehensive and multidimensional perspective of control effect, safety, price and actual market needs, dichlorvos EC and imidacloprid WP are relatively economical, easy to purchase, and achievable in basic control effect in the control of Geisha distinctissima in photinia fraseri in real production.