›› 1998, Vol. 41 ›› Issue (4): 382-388.

• RESEARCH PAPERS • Previous Articles     Next Articles

INFESTATION LEVELS OF DIURAPHIS NOXIAMORDVILKO RESPONSE TO PRECIPITATION AND IRRIGATION

Liang Hongbin Zhang Runzhi Zhang Guangxue Wen Yonglin Wang Guoping   

  • Received:1998-02-09 Online:1998-11-20 Published:1998-05-20

Abstract: The infestation levels of Diuraphis noxia Mordvilko were investigated in correlation to the amount of rainfall in 1989-1996 in Xinjiang Uygur Autonomous Region. The effects of simulated rainfall on aphid population were observed both in the field and in the lab. D. noacia was sampled from fields at different irrigation levels. Theresults indicated that aphid infestation was negatively correlated to the amount of rainfall in April and May (r=-0.92), but positively correlated to the amount of rainfall inlate July of previous years (r=0.67). The amount of rainfall (X) in April and May was regressed with aphid population (Y) as Y= 4. 9-0.048X. The aphid population was significantly suppressed by stimulated rainfall in field and in lab experiments. Droughtstressed plants were infested with more aphids than drought-free plants. The percentage of D. Noxia parasitized by Diaeretieua rapae M'Intosh was greater on drought-freeplants than that on drought-stressed plants. (Tacheng Plant Protection Station, Tacheng 834700)Abstract The infestation levels of Diuraphis noxia Mordvilko were investigated in correlation to the amount of rainfall in 1989-1996 in Xinjiang Uygur Autonomous Region. The effects of simulated rainfall on aphid population were observed both in the field and in the lab. D. noacia was sampled from fields at different irrigation levels. Theresults indicated that aphid infestation was negatively correlated to the amount of rainfall in April and May (r=-0.92), but positively correlated to the amount of rainfall in late July of previous years (r=0.67). The amount of rainfall (X) in April and May wasregressed with aphid population (Y) as Y= 4. 9-0.048X. The aphid population was significantly suppressed by stimulated rainfall in field and in lab experiments. Drought-stressed plants were infested with more aphids than drought-free plants. The percentageof D. Noxia parasitized by DiaeretieUa rapae M'Intosh was greater on drought-free plants than that on drought-stressed plants.

Key words: Diuraphis noaxia Mordvilko, precipitation, population dynamic