›› 1997, Vol. 40 ›› Issue (3): 288-296.

• RESEARCH PAPERS • Previous Articles     Next Articles

A STUDY ON THE MORPHOLOGY AND LIFE HISTORY OF ALLOTHROMBIUM OVATUM (ACARIFORMES:TROMBIDIIDAE)

Zhang Huijie Li Jianshe Xian Shuanshi   

  • Online:1997-08-20 Published:1997-08-20

Abstract: Allothrombiurn ovaturn is an ectoparasitic natural enemy of the cotton aphidAphis gossypii in North China. By laboratory rearing and field observations, it was found that this mite has one generation a year in Shanxi Province and overwinters in egg stage in soil. The developmental durations of egg stage, prelarva, larva, nymphochrysalis, nymph, preadult and adult were found to be 220.3, 19.5, 22.0, 12.0, 13.0, 13.0 and 59.0 days respectively at the mean annual temperature 13.7℃. Its seasonal occurrence was recorded in the field in Shanxi Province. The larvae appear in late spring and early summer, and the nymphs and adults emerge in summer and autumn. The morphology and habits of the developmental stages are described.

Key words: Allothrombiurn ovatum, life history, habit