六个品种小麦对玉米象的抗虫性比较研究

Comparative study on resistance of six varieties of wheat to maize weevil

试验选用产自河北、河南、山东等省的6个小麦品种,分别是良星66、泛麦8号、西农979、郑麦7698、济麦22和矮抗58。从田间获取的样品分别将其水分含量调节为12.5%左右,每16 g粮食感染6头母代玉米象成虫(雌雄比为4∶2),之后检查其子代成虫羽化数量,羽化时间,并计算发育历期和敏感系数。主要结果为:济麦22中的玉米象平均发育历期最短(40.8 d),子代成虫数量最多(46头),对玉米象的敏感系数为9.40;西农979中的玉米象平均发育历期为42.6 d,子代成虫数量为8头,对玉米象的敏感系数为4.98。抗虫性最小的济麦22中玉米象子代成虫羽化初现时间、羽化高峰和终止时间都相应地是最短,抗虫性最大的西农979中害虫初现时间和终止时间有所延长,但并非最大值。良星66中的玉米象羽化终止时间最长,但其抗虫性却小于西农979。由样品感染卵至成虫初现的过程中小麦品种间的重量变化量差异不显著。结果表明:试验小麦品种间对玉米象的抗虫性差异显著,子代成虫出现数量多的小麦品种其敏感系数也相应地小,但羽化时间长短与小麦的敏感系数大小变化趋势不完全一致,小麦感染害虫后重量下降量与其敏感性相关性不明显。

Six varieties of wheat were selected from Hebei, Henan and Shandong provinces, which were LiangXing 66, Fanmai 8, Xinong 979, Zhengmai 7698, Jimai 22 and Aikang 58, respectively. The moisture content of grain was adjusted to 12.5% after sampling from field. Each test sample in weight of 16 grams was infested by six parent weevils which ratio of female to male was four to two. The emergence time and progeny number of adults, weight changes of test sample were checked. And the sensitive coef- ficient was calculated according to the checked data. The results showed that in Jimai22 the mean devel- opment duration of the insect was shortest, for 40.8 days, and the number of progeny was biggest, 46 a- dults. The sensitive coefficient of Jimai22 to the weevil was 9.40. In Xinong979 the mean development duration of the insect was 42. 6 days. The number of progeny was 8 adults. And the sensitive coefficient of Xinong979 was 4.98. The beginning time, peak number time and ending time of adult eclosion for the insect was gotten short for Jimai22 that the resistance to insects was on the lowest level. For Xinong979 that the resistance to insects was on top level, the beginning time and ending time of adult eclosion werebigger than others, but than that of Xinong979, weight of samples in the not the biggest number. For Liangxing66 that the resistance to insects was less the ending time was longer than days from the insect egg infesting that of others. There was a little of change on to beginning time of adult eclosion. The results showed that there were obvious differences in resistance to insects between wheat varieties. The smaller sensitive coefficient was, the more the progeny number was. The eclosion duration was not entirely con- sistent with trends of sensitive coefficient; and there was no obvious correlation between the sensitive co- efficient and the weight change of wheat infested by the insect.