Electropenetrography (EPG) was used to study the feeding preference of Brevicoryne brassicae Linnaeus (Hemiptera: Aphididae) on Brassica napus L. We assessed the probing behaviors of B. brassicae on three B. napus cultivars (Qinyou10, Zhongheza88, and Qinyou79) at three developmental stages (two leaf, four leaf, and six leaf stages). The four leaf treatment had a shorter duration of pathway phase and a longer time to first intracellular stylet punctures on Qinyou10 compared to other cultivars, and the longest total ingestion duration on Qinyou10 and the shortest on Qinyou79, indicating a preference for Qinyou10 over Qinyou79. This cultivar preference is also reflected in the field with higher aphid densities on Qinyou10 in the previous investigation. In the two leaf treatment, we found a longer total probing duration and a shorter non-probing duration on Zhongheza488 compared to Qinyou10. In the six leaf treatment, we found a longer duration in time to the first probe, more probes, and longer duration of non-probing on Qinyou10 compared to other cultivars. However, phloem associated behaviors were not significantly influenced by cultivar in the latter two treatments. We conclude that future research should focus on phloem associated behaviors on the four leaf stage of B. napus in order to evaluate cultivars resistant to B. brassicae.

abstract in chinese:利用昆虫刺探电位图谱技术 (EPG) 评估甘蓝蚜在油菜植株上的取食偏好性。我们选取三个油菜品种 (秦优10, 中核杂488以及秦优79) 分别在二叶期、四叶期和六叶期对甘蓝蚜的取食行为进行研究。结果显示:四叶期, 相比于其它品种, 蚜虫在秦优10上展示了更短的路径期以及需要更长的时间才出现第一次细胞内口针穿刺, 特别是在三个品种中, 蚜虫在秦优10上的取食期最长, 在秦优79上的取食期最短, 说明相比于秦优79, 甘蓝蚜更喜欢在秦优10上取食。蚜虫在秦优10上显示的偏好性也正好匹配我们以前的田间调查的结果, 即秦优10上的蚜虫密度更高。在二叶期, 我们发现在中核杂488上蚜虫比在秦优10上探测的时间更长, 非探测的时间更短。在六叶期, 相比于其它品种, 蚜虫在秦优10上需要更长的时间才开始刺探并且产生大量的非刺探间隔, 和较长的非刺探时间。然而, 在二叶期和六叶期, 与韧皮部相关的行为在三个品种间没有显示出统计上的差异。所以, 我们认为将来的研究应该聚焦于蚜虫在四叶期油菜上的韧皮部相关行为来评估品种对蚜虫的抗性。