Cao H-H, Pan M-Z, Liu H-R, Wang S-H, Liu T-X
State Key Laboratory for Crop Stress Biology for Arid Areas,Northwest A&F University,Yangling,Shaanxi 712100,China.
Innovation Experimental College,Northwest A&F University,Yangling,Shaanxi,China.
Bull Entomol Res. 2015 Aug;105(4):448-55. doi: 10.1017/S0007485315000322. Epub 2015 Apr 21.
Continuous ingestion of the phloem sap of plants by aphids can remove a significant amount of photoassimilates. Based on our earlier works, we hypothesized that due to the reduced aphid feeding time caused by antibiosis, wheat plants may achieve growth tolerance to aphids. We tested this hypothesis using three wheat cultivars, XY22 (Xiaoyan22), AK58 (Bainongaikang58) and XN979 (Xinong979) and the grain aphid, Sitobion avenae. In the choice test, S. avenae did not show any preference among the three wheat cultivars. However, S. avenae had a lower body weight and a lower intrinsic rate of increase when feeding on XY22 than on AK58 and XN979. The electrical penetration graph results indicated that S. avenae had significantly shorter mean and total phloem ingestion periods on XY22 than on AK58 or XN979. The aphids required a similar time to reach the phloem sap on the three wheat cultivars, but required more time to establish sustained phloem ingestion on XY22. These results suggest that the resistance factors of XY22 may be phloem based. Moreover, XY22 suffered less biomass loss in response to aphid infestation compared with XN979, suggesting that XY22 also had a better growth tolerance to S. avenae than XN979. Wheat resistance level to S. avenae was partially correlated with plant photosynthetic rates, and peroxidase activities. These results confirmed that the limitation in aphid feeding from plant phloem in wheat cultivar XY22 was related to antibiosis but not antixenosis, which caused XY22 tolerance to S. avenae.
蚜虫持续摄取植物韧皮部汁液会消耗大量光合产物。基于我们早期的研究，我们推测由于抗生性导致蚜虫取食时间减少，小麦植株可能对蚜虫具有生长耐受性。我们使用三个小麦品种，即XY22（小偃22）、AK58（百农矮抗58）和XN979（西农979）以及麦长管蚜来验证这一假设。在选择试验中，麦长管蚜在这三个小麦品种之间没有表现出任何偏好。然而，以XY22为食时，麦长管蚜的体重较低且内禀增长率也较低，相比之下，以AK58和XN979为食时则不然。刺探电位图谱结果表明，麦长管蚜在XY22上的平均韧皮部取食期和总韧皮部取食期显著短于在AK58或XN979上。蚜虫在这三个小麦品种上到达韧皮部汁液所需时间相似，但在XY22上建立持续韧皮部取食需要更多时间。这些结果表明，XY22的抗性因子可能基于韧皮部。此外，与XN979相比，XY22在遭受蚜虫侵害时生物量损失较少，这表明XY22对麦长管蚜的生长耐受性也优于XN979。小麦对麦长管蚜的抗性水平与植物光合速率和过氧化物酶活性部分相关。这些结果证实，小麦品种XY22中蚜虫从植物韧皮部取食受限与抗生性有关，而非排趋性，这导致了XY22对麦长管蚜的耐受性。
