Generation And Identification Of Transgenic Wheat Plants Expressing Glyoxylate Dehydrogenase And Antifungal Peptide Genes

Wheat is one of the staple food worldwide. The low photosynthetic efficiency is one of the key factors limiting wheat yield. Thus, the improvement of photosynthetic capacity plays a vital role in increasing wheat yield. Fusarium Head Blight(FHB) not only reduces wheat production, but also contaminates grain by fungal-secreted mycotoxins such as deoxynivalenol(DON). Increasing wheat photosynthic efficiency and resistace to FHB has a significant value in argriculture production. Neverthless, because of poor wheat germplasm pool, the improvement reaches the plateau through conventional breeding. Obtaining the high-yield and FHB-resistance cultivars by genetic enginieering provides a brand new way for wheat breeding.This paper transformed glycolate dehydrogenase gene and FHB-resistant genes into Xiangmai 76 through particle bombardment. Several transgenic lines were obtained by PCR identification. The main results are as follows:1. Two minimal gene cassettes each containing glycolate dehydrogenase gene SAR-UBI-Ta CTP-DEF-NOS-SAR and FHB-resistant gene SAR-LEM2-UECH42-D2-HIS-NOS-SAR co-transforming Xiangmai 76. One primary transgenic line carrying both transgenes was obtained through BAR/Bialaphos screening and PCR identification, labling H7. Through cultivation in greenhouse, the T4 transgenic lines were obtained. The RT-PCR indentification proved the exogenous genes expressing in the RNA level, the field single-floret inoculation stated the improving resistance to FHB, and field grain test showed the higher yield of transgenic wheat.2. Two minimal gene cassettes each carrying glycolate dehydrogenase gene SARUBI-Ta CTP-DEF-NOS-SAR and FHB-resistant gene SAR-LEM2-UECH42-D2-HISNOS-SAR co-transforming Xiangmai 76. Three primary transgenic lines were obtained, naming H8, H9, and H11. All transgenic lines contained both transgenes. Through cultivation, the transgenic lines are T2 progeny now.3. Two minimal gene cassettes each containing glycolate dehydrogenase gene SAR-CMPS-Ta CTP-DEF-NOS-SAR and FHB-resistant gene SAR-UBI-EXD4E1-A6-HIS-NOS-SAR co-transforming Xiangmai 76. Through tissue culture and selection of BAR/Bialaphos, two stable inherited primary lines carrying DEF were obtained, marking M3, M11. Now, they are in T2 progeny.4. Two minimal gene cassettes each carrying FHB-resistant genes SAR-UBI-BLFNOS-SAR and SAR-LEM2-HVCHI-G7-NOS-SAR co-transfoming Xaingmai 76. Trough BAR/Bialaphos selection, two transgenic lines having both genes were obtained, labling D5, D11, now they are in T2 progeny; through PMI/Mannose screening, two primary transgenics were harvested, marking D13, D14, now they are in T1 progeny.5. Three minimal gene cassettes each containing FHB-resistant genes SARDUBI35SS-CHS3b-A5-I-S5-CHS3b-A1-I-S1-NOS-SAR, SAR-DUBICMPS-CHS3bA2-I-S2-CHS3b-A3-I-S3-NOS-SAR, SAR-DUBI35SS-CYP51BAC-DNOS-SAR cotransforming Xiangmai 76. Trough PMI/Mannose screening, five different primary transgenics were obatained. Three lines, labling X1, X2, and X7, have two genes CHS3b-A2 and CYP51 BAC. The other two lines, naming X5 and X6, only have CYP51 BAC gene. They are all in T1 progeny now.