用RT-PCR和cDNA-AFLP方法研究了两个不同抗性水平的小麦品种在不同危害时间后6个特异选择的基因和全部基因的差异表达.结果表明,在感蚜品种千斤早中,48 hLOX表达最充分,而在抗蚜品种ASTRON中,LOX基因在72 h时才表达最强.AOS基因在感蚜品种千斤早中与LOX表达一致,48 h表达最强,在抗蚜品种ASTRON中,AOS基因持续表达.PDF1.2基因在抗蚜品种ASTRON中持续表达,但在感蚜品种千斤早中仅在48 h有较强的表达.PAL基因在不同时间段内都无明显表达差异.PR-1基因在抗蚜品种ASTRON中,在72、96 h诱导表达,而在感蚜品种千斤早中不表达.BGL2基因在抗蚜品种ASTRON中,48 h后有较强的表达,而在感蚜品种千斤早中也无明显表达.通过cDNA-AFLP分析,进一步验证了不同危害时间、不同品种间的基因差异.从这些差异的基因中分离了10个基因并对其序列进行了分析,结果表明,蚜虫取食诱导的防卫反应涉及十八烷酸途径和病菌相关蛋白.
In order to demonstrate the difference in plant defense response after aphid feeding, six specific genes and differential expression genes in two resistant varieties in different time were analyzed through using RT-PCR and cDNA-AFLP. The results showed that LOX gene expresses highly in 48 h in susceptible variety and strongly induces in 72 h in resistant variety. The gene of AOS is parallel to LOX in susceptible variety, but AOS always expresses in resistant variety. The PDF1.2 expresses all the times in resistant variety, but only 48 h in susceptible variety. There is no difference on PAL gene in two varieties. In resistant variety, PR-1 gene is induced in 72 h and 96 h but no change in susceptible variety. BGL2 expresses strongly after 48 h in resistant variety, but no expression in susceptible variety. The cDNA-AFLP results demonstrated many differential expression genes after aphid feeding from in two wheat varieties. We isolated ten genes randomly and analyzed their sequence. The defense involved octadecanoid pathway and pathogenesis-related proteins.