Evaluating the impacts of refuge width on source-sink dynamics between transgenic and nontransgenic cotton - art. no. 3
Evaluating the impacts of refuge width on source-sink dynamics between transgenic and nontransgenic cotton - art. no. 3
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DOI：
10.1093/jis/4.1.3
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发表时间：
2004-01-01
影响因子：
2.2
通讯作者：
Hankins, G
中科院分区：
文献类型：
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作者：
Caprio, MA;Faver, MK;Hankins, G
Bt转基因作物的抗性管理部分依赖于在无毒避难所中产生足够数量的易感昆虫。模拟模型表明，源-汇动态可以与避难所的结构相互作用，影响这些地区的昆虫生产。我们测试的假设，改变隔离庇护所和转基因棉花通过操纵嵌入棉田内的庇护所的宽度会改变密度的Heliothis virescens和Helicoverpa zea产卵在避难所。在两年的时间里，对三类避难所宽度进行了测试：它们包括窄（16 - 24米宽）、中等（32 - 48米宽）和宽（80 - 96米宽）避难所。两种生境之间的隔离度随着避难所宽度的增加而增加。1996年，以H. virescens，H.玉米没有区别，但一个显着增加的卵密度和显着降低的相对产量（避难所产量相比，从直接周围的Bt-棉花的产量）被发现作为避难所宽度增加。1997年，用H. virescens与H.玉米使用ELISA测试。H.随着避难所宽度的增加，绿僵菌卵的数量增加，而绿僵菌密度则显著下降。随着离避难所距离的增加，virescens卵。避难所宽度对H.玉米卵，也不是一个回归的斜率的蛋密度和距离避难所显着不同的零。我们认为这些差异反映了两种昆虫生物学上的差异。
Resistance management for Bt-transgenic crops relies in part on the production of sufficient numbers of susceptible insects in non-toxic refuges. Simulation models suggested that source-sink dynamics could interact with the structure of refuges to impact the production of insects in these areas. We tested the hypothesis that altering isolation between refuges and transgenic cotton by manipulating the width of refuges embedded within cotton fields would alter the density of Heliothis virescens and Helicoverpa zea eggs oviposited in refuges. Three categories of refuge widths were tested over two years: they included narrow (16- 24m wide), medium (32- 48m wide) and wide (80- 96m wide) refuges. Isolation between the two habitats increased as refuge width increased. In 1996, eggs of H. virescens from H. zea were not distinguished, but a significant increase in the density of eggs and a significant decrease in relative yield ( refuge yield compared to the yield from immediately surrounding Bt-cotton) was found as refuge width increased. In 1997, eggs from H. virescens were analyzed separately from H. zea using an ELISA test. The density of H. virescens eggs increased with increasing refuge width, and there was a significant decline in density of H. virescens eggs with increasing distance from the refuge. In contrast, there was no impact of refuge width on the density of H. zea eggs, nor was the slope of a regression of egg density and distance from the refuge significantly different from zero. We suggest that these differences reflect differences in the biology of the two insects.