云南西双版纳橡胶盔蚧种群动态及影响因子的初步研究

Preliminary studies on population dynamics of the scale insect Parasaissetia nigra on rubber trees and influencing factors in Xishuangbanna

2005年4月至2008年3月连续在云南省西双版纳对橡胶盔蚧(Parasaissetia nigra Nietner)种群密度进行调查,结果表明:橡胶盔蚧周年发生,不同年份相同时期虫口密度存在显著差异(p<0.05)。2007年7月和10月虫口密度达到最高,分别为(108.5±11.9)头/枝和(107.2±5.5)头/枝。各虫态的虫口数量在1年的周期内均呈现3个高峰,若虫高峰为4月、7月和10月(2006年为12月),成虫高峰为1月、6月和10月。在旱季,温度是影响种群的主要因素;在雨季,降水强度和频率是制约种群增长的关键因子。

Investigations on population dynamics of the rubber tree scale insect Parasaissetia nigra were carried out from April 2005 to March 2008 in Xishuangbanna rubber plantation. The results showed that this scale insect occurred in this region year by year. The population density of the scales at the same month was significantly different among different years （One-Way ANOVA, p〈0. 05）. The density reached highest in July and October in 2007, at 108.5± 11.9 and 107.2±5.5 individuals per branch, respectively. There were three density peaks for the scales of various stages. As for the nymphs, the first peak appeared in early April, and the second in the middle of July, and the third in October （December in 2006）. The density peaks of the adult scales occurred in January, June and October, respectively. Analysis combined with climatic factors demonstrated that the temperature was the main factor affecting the population dynamics of the scale insects in dry seasons, and the intensity and frequency of rainfall was the key factor restricting the growth of scale populations in wet seasons.