Pan Hongsheng, Liu Bing, Lu Yanhui, Desneux Nicolas
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
French National Institute for Agricultural Research (INRA), Sophia-Antipolis, France.
PLoS One. 2014 Apr 4;9(4):e94190. doi: 10.1371/journal.pone.0094190. eCollection 2014.
Understanding the effects of weather on insect population dynamics is crucial to simulate and forecast pest outbreaks, which is becoming increasingly important with the effects of climate change. The mirid bug Apolygus lucorum is an important pest on cotton, fruit trees and other crops in China, and primarily lays its eggs on dead parts of tree branches in the fall for subsequent overwintering. As such, the eggs that hatch the following spring are most strongly affected by ambient weather factors, rather than by host plant biology. In this study, we investigated the effects of three major weather factors: temperature, relative humidity and rainfall, on the hatching rate of A. lucorum eggs overwintering on dead branches of Chinese date tree (Ziziphus jujuba). Under laboratory conditions, rainfall (simulated via soaking) was necessary for the hatching of overwintering A. lucorum eggs. In the absence of rainfall (unsoaked branches), very few nymphs successfully emerged under any of the tested combinations of temperature and relative humidity. In contrast, following simulated rainfall, the hatching rate of the overwintering eggs increased dramatically. Hatching rate and developmental rate were positively correlated with relative humidity and temperature, respectively. Under field conditions, the abundance of nymphs derived from overwintering eggs was positively correlated with rainfall amount during the spring seasons of 2009-2013, while the same was not true for temperature and relative humidity. Overall, our findings indicate that rainfall is the most important factor affecting the hatching rate of overwintering A. lucorum eggs on dead plant parts and nymph population levels during the spring season. It provides the basic information for precisely forecasting the emergence of A. lucorum and subsequently timely managing its population in spring, which will make it possible to regional control of this insect pest widely occurring in multiple crops in summer.
了解天气对昆虫种群动态的影响对于模拟和预测害虫爆发至关重要，随着气候变化的影响，这一点变得越来越重要。盲蝽象是中国棉花、果树和其他作物上的一种重要害虫，主要在秋季将卵产在树枝的枯死部分以便越冬。因此，次年春天孵化的卵受环境天气因素的影响最大，而非寄主植物生物学特性。在本研究中，我们调查了温度、相对湿度和降雨这三个主要天气因素对在枣树（枣属）枯死枝条上越冬的盲蝽象卵孵化率的影响。在实验室条件下，降雨（通过浸泡模拟）是越冬盲蝽象卵孵化所必需的。在没有降雨的情况下（未浸泡的枝条），在任何测试的温度和相对湿度组合下，很少有若虫成功羽化。相比之下，模拟降雨后，越冬卵的孵化率显著提高。孵化率和发育率分别与相对湿度和温度呈正相关。在田间条件下，2009 - 2013年春季，越冬卵孵化出的若虫数量与降雨量呈正相关，而与温度和相对湿度无关。总体而言，我们的数据表明降雨是影响越冬盲蝽象卵在枯死植物部分的孵化率以及春季若虫种群数量水平的最重要因素。它为精确预测盲蝽象的羽化以及随后及时控制其春季种群数量提供了基础信息，这将使得在夏季对这种广泛发生在多种作物上的害虫进行区域控制成为可能。
