Abstract: Plant lectins have been shown to be toxic to sap-sucking pest such as wheat aphids.In order to obtain the potential lectin gene and aphid-resistant wheat germplasm,a sNTL (synthesized Narcissus tazetta lectin) gene was synthesized using the Gene Shuffling method and the transgenic wheat lines were produced to check the resistance to aphid.In this study,a sNTL gene encoding mannose binding lectins was synthesized according to the codon preferences of wheat genes,and driven by constitutive and phloem-specific rbcs promoter in the constructs.The sNTL gene was transferred into two wheat cultivars (Zhongyou 9507 and Fengyou 6) by particle bombardment transformation.After selected by BASTA and differentiation,twenty-eight T₀ transgenic plants were generated.The integration and transcription of the sNTL gene were confirmed by PCR and RT-PCR analysis respectively.Insect bioassay on detached leaf segments reveal:the aphid mortality of sNTL transgenic wheat lines ranged from 53.1% to 59.4%.The highest aphid mortality was found in sNTL transgenic line zy9-4,and the rate was 24.8% higher than that of the Zhongyou 9507 control,followed by fy4-2 with 14.1% higher aphid mortality and 33.4% lower aphid growth rate than that of the Fengyou 6 control.Insect bioassay in isolated field showed that aphids number per tiller of transgenic lines zy9-4,zy9-8,fy4-2 and fy4-4 were decreased by 51.4%,45.1%,58.7% and 76.9% respectively compared with corresponding control plants.The sNTL transgenic lines were found to be highly resistant to aphids compared to the corresponding control plants.Therefore,sNTL is a strong biotechnological candidate for use in efforts to produce aphid-resistant wheat using genetic modification approachs.

Key words: sNTL gene, Transgenic wheat, Wheat aphid, Insect resistance

CLC Number: 

• Q78

• S435.12