B烟粉虱危害对葫芦科3种寄主植物生长发育的影响

采用直尺测量和烘箱烘干及分光光度法测定B烟粉虱为害后西葫芦、瓠瓜、丝瓜的生长指标及叶绿素含量,比较葫芦科不同种类寄主植物被B烟粉虱为害后在生长发育方面的差异,探讨B烟粉虱对寄主植物生长影响差异的机制。结果表明,B烟粉虱为害对3种葫芦科寄主生长有明显的不利影响,与各自无虫对照植株相比,西葫芦株高、茎粗、叶面积和单位面积干重均显著降低。与对照植株相比,西葫芦受害30天后,株高、茎粗和叶面积的抑制率分别为35.08%、4.38%和20.73%;单位面积干重较对照降低了31.86%。受害的丝瓜与对照植株相比仅株高明显降低,抑制率为31.47%;而茎粗、叶面积、单位面积干重均没有明显降低。瓠瓜受害30天后,株高和节间距与对照相比显著增加,株高抑制率为-28.69%,节间距抑制率为-42.63%,但茎粗和单位面积干重较对照显著降低。生化测定结果发现,B烟粉虱危害后,3种寄主植物叶片叶绿素含量均显著下降,其中以西葫芦最为显著,与对照相比,叶绿素a含量降低了68.22%,叶绿素b含量降低了64.63%。

Effect of Bemisia tabaci B Infestation on Growth of Three Cucurbitaceae Host Plants

In this study, the effect of Bemisia tabaci B infestation on the growth and development of zucchini, pepo and towel gourd were investigated through measuring the growth indexes and chlorophyll content of these three Cucurbitaceae host plants by ruler measurement, oven drying and spectrophotometry after B. tabaci infestation. The results showed that feeding of B. tabaci B had a significant negative effect on the growth of all the three Cucurbitaceae host plants. After 30 d of infestation, the plant height, stem diameter and leaf area of zucchini all significantly decreased, with an inhibition ratio of 35.08%, 4.38% and 20.73%, respectively, compared with the uninfested plants, and the dry weight was 31.86% lower than that of the control. Plant height of the affected towel gourd significantly reduced compared with that of uninfested control plants, and the inhibition rate was 31.47%, while the stem diameter, leaf area and dry weight of towel gourd were not significantly affected after B. tabaci infestation. Similarly, the stem diameter and dry weight of pepo all obviously decreased compared with that of the control plants, however, the plant height and internode length of pepo increased, with an inhibition rate of -28.69% and -42.63%, respectively. Biochemical assays showed that the leaf chlorophyll content of the three host plants decreased significantly after B. tabaci B infestation, especially the zucchini, of which the chlorophyll a and b content decreased by 68.22% and 64.63%, respectively.