Development of transgenic wheat (Triticum aestivum L.) expressing avidin gene conferring resistance to stored product insects

Background: Wheat is considered the most important cereal crop all over the world. The wheat weevil Sitophilus granarius is a serious insect pests in much of the wheat growing area worldwide and is responsible for significant loss of yield. Avidin proteins has been proposed to function as plant defense agents against insect pests. Results: A synthetic avidin gene was introduced into spring wheat (Triticum aestivum L.) cv. Giza 168 using a biolistic bombardment protocol. The presence and expression of the transgene in six selected T-0 transgenic wheat lines were confirmed at the molecular level. Accumulation of avidin protein was detected in transgenic plants compared to non-transgenic plants. Avidin transgene was stably integrated, transcribed and translated as indicated by Southern blot, ELISA, and dot blot analyses, with a high level of expression in transgenic wheat seeds. However, no expression was detected in untransformed wheat seeds. Functional integrity of avidin was confirmed by insect bioassay. The results of bioassay using transgenic wheat plants challenged with wheat weevil revealed 100 % mortality of the insects reared on transgenic plants after 21 days. Conclusion: Transgenic wheat plants had improved resistance to Sitophilus granarius.