The Molecular Identification And Analysis On Resistance To Aphids Of Transgenic Ubi::Hpa1_10-42 Wheat Plants

Aphids as one of the major pests could cause severe damage to the yield and qualityof wheat in the world. It could damage to crops not only by feeding directly，but also byspreading much virus. The using of chemical pesticide could control aphids over a periodof time, but it may cause that environment was severly polluted, a large number of aphidswere killed. So it also endangered the life of people and animals. In addition, because oflong-period and limit of resistant sources, it was difficμlt to get the resistant varieties bytraditional breeding method. Consequently, with the development and application of plantgene engineering, the molecular breeding method has gained more and more attentionwhich took anti-insect genes cloning and transformation as the core.The Hpa1_10-42gene was transferred into Yangmai16by particle bombardment.Transgenic wheat plants were identified by PCR, Southern blotting and RT-PCR, theresistance to aphids was tested, and the changes of activity of POD and CAT and contentsof soluble protein and tannin acid were analyzed. We also evaluated the Hpa1_10-42geneinfluence to agronomic trait and quality of transgenic wheat plants. The major results areas follows:1．The PCR and Southern blot results showed that the alien Hpa1_10-42was integratedwith different copies and was inherited in transgenic wheat lines. The PPT resistanceidentification and RT-PCR analysis results indicated that the foreign gene Hpa1_10-42wasnomorally expressed in transgenic wheat plants.2．Aphids grow and reproduced naturally without using any pesticides in Yangmai16andT2transgenic wheat plants which were tested positive by PCR. In order to evaluate theresistance to aphids of transgenic wheat plants, the number of aphids was investigated at fullincidence period in the plants. The results showed that the resistance to aphids of transgenicwheat plants was significant higher than Yangmai16, and reached the highly significant level.This showed that the integration of foreign Hpa1_10-42gene increased the resistance to aphidsof transgenic wheat plants.3．The change of physiological and biochemical index was studied in Yangmai16andtransgenic wheat lines. The result showed that the POD and CAT activity and tannin acid content were significantly higher than Yangmai16, but the content of soluble protein weresignificantly lower than Yangmai16. These provided a foundation for the study aboutmechanism of resistance to aphids.4．In order to study the influence of Hpa1_10-42genes insertion, agronomic trait andquality index were determined in T2transgenic wheat plants. It was shown that plant heightof all transgenic lines decreased significantly than the control, but spike length, spikeletnumber and grain weight highly significantly increased. In addition, there was no significantdifference in internode length under spike and flag leaf width between all transgenic lines.Two lines of amylose, amylopectin and total starch content were significantly higher thanYangmai16, and one line had no significant difference. The content of protein had nosignificant difference in all transgenic lines. This showed that insertion of foreign Hpa1_10-42gene had influence on some agronomic and quality traits.In a word, aphid-resistant transgenic wheat plants were screened out by moleculardetection, resistance identification and the measuring to agronomic trait and quality index.Meanwhile, the change of physiology and biochemistry indexes was analyzed. These resultslay a foundation for researching the mechanism of wheat resistance to aphids.