Hou Maolin, Lin Wei, Han Yongqiang
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
Environ Entomol. 2009 Aug;38(4):1182-8. doi: 10.1603/022.038.0427.
The Asiatic rice borer Chilo suppressalis (Walker) occurs mainly on rice Oryza sativa L. and water-oat Zizania latifolia (Turcz). Certain ecological and physiological differentiations between rice and water-oat populations have been shown. To determine whether there is host-associated differentiation in supercooling capacity, seasonal changes in supercooling points, glycerol content, and other physiological parameters of naturally occurring C. suppressalis larvae overwintering in rice and water-oat plants were compared over the winter. Supercooling points were low in the winter (November and December), significantly higher in March, and significantly lower in the water-oat population than in the rice population in the winter. Larvae from the water-oat population experienced a significant weight loss from December to March and were heavier than those from the rice population in the winter. Body water content (percentage of fresh weight) was low in the winter and increased significantly in March; no population differences were detected. Hemolymph glycerol content was high in the winter and dropped significantly in March; interpopulation differences were significant in December. Hemolymph trehalose content increased in the winter, and no population differences were detected. Whole body glucose and lipid content varied differently between the rice and the water-oat populations over the winter. It was found that variations in hemolymph glycerol content were responsible for the host-associated seasonal changes in supercooling capacity of overwintering larvae of the Asiatic rice borer.
二化螟Chilo suppressalis（Walker）主要寄生于水稻Oryza sativa L.和茭白Zizania latifolia（Turcz）上。已有研究表明水稻和茭白种群之间存在某些生态和生理分化。为了确定过冷却能力是否存在寄主相关分化，对冬季在水稻和茭白植株上自然越冬的二化螟幼虫的过冷却点、甘油含量和其他生理参数的季节性变化进行了比较。冬季（11月和12月）过冷却点较低，3月显著升高，且冬季茭白种群的过冷却点显著低于水稻种群。茭白种群的幼虫在12月至3月体重显著减轻，且冬季比水稻种群的幼虫更重。冬季虫体含水量（鲜重百分比）较低，3月显著增加；未检测到种群差异。血淋巴甘油含量在冬季较高，3月显著下降；12月种群间差异显著。血淋巴海藻糖含量在冬季增加，未检测到种群差异。整个冬季，水稻和茭白种群的虫体葡萄糖和脂质含量变化不同。研究发现，血淋巴甘油含量的变化是导致二化螟越冬幼虫过冷却能力出现寄主相关季节性变化的原因。
