Browsing by Author "Parajulee, MN"

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Evaluation of Winter Wheat as a Potential Relay Crop for Enhancing Biological Control of Cotton Aphids in Seedling Cotton
(Springer, 2004) Men, XY; Ge, F; Yardim, EN; Parajulee, MN
A 2-year study was conducted to evaluate the role of winter wheat, Triticum aestivum L., as a potential relay crop to conserve arthropod natural enemies and suppress cotton aphids, Aphis gossypii Glover, in seedling cotton. The results suggested that the natural enemies that moved from the adjacent wheat fields to cotton fields with the maturity and harvest of wheat could keep the cotton aphid population at the edges (0-4 m) of cotton fields under the action threshold of 100 aphidS/m(2). Data also suggested that the wheat strip served as a reservoir to conserve arthropod predators and "relayed" its predators to cotton when wheat matured and senesced.
Quantification of Diapausing Fourth Generation and Suicidal Fifth Generation Cotton Bollworm, Helicoverpa Armigera, in Cotton and Corn in Northern China
(Blackwell Publishing, 2005) Ge, F; Chen, F; Parajulee, MN; Yardim, EN
Cotton bollworm, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), is a major pest of cotton and corn crops in northern China. A phenological differentiation between fourth generation cotton bollworms from cotton and those from corn fields was observed in northern China during 1999-2000. The proportion of pupation in late fall was marginally higher in cotton fields compared to that in corn fields; however, the proportions of fall emergence of moths from cotton fields were significantly higher than those from corn fields. The proportion of spring emergence of moths was also significantly higher for larvae collected from cotton (28.0%) than from corn (14.5%). The overwintering duration of females was significantly shorter than that of males in both crops. Moreover, the overwintering duration of bollworm populations from cotton was significantly longer than that from corn. The early spring population of H. armigera came from both cotton and corn fields, but the spring emergence of moths from larvae collected from cotton took about 5 days longer to reach 100% emergence compared to that from corn.