Defense responses of transgenic MINELESS and wild-type oilseed rape (Brassica napus L.) against aphids

The endogenous protein complex myrosinase and glucosinolates form a defense system in cruciferous plants against insect pests. Transgenic ablation of myrosin cells produced MINELESS seeds of Brassica napus used to investigate plant-aphid interactions. In the present study, we conducted a non-choice experiment to test the performance and fecundity of the aphids Brevicoryne brassicae (specialist) and Lipaphis erysimi (generalist) on MINELESS transgenic seedlings and the wild-type cultivar Westar. Feeding preference showed that B. brassicae preferred wild-type seedlings and L. erysimi preferred MINELESS. Progeny of generalist and specialist aphids establish and affect wild-type and MINELESS seedlings differently. Glucosinolate hydrolysis products were higher under the influence of B. brassicae in both wild-type and MINELESS seedlings. In addition, allyl isothiocyanate decreased under the influence of L. erysimi, except 3,4 -epithiobutane nitrile. Infestation by L. erysimi induced the reduction of glucosinolates, whereas B. brassicae had an opposite effect. In conclusion, the present study showed that myrosin cells affected the preference of aphid species for Brassica napus plants.