Study on Differentially Lipase Gene Expression against Different Inducers of Defense Response in Scab-Resistant and Susceptible Wheat Cultivars

Fusarium graminearum is the pathogenic agent of Fusarium head blight (FHB), which is a destructive disease on wheat and barley, thereby causing huge economic loss and health problems to human by contaminating foods. Chinese cultivar, sumai3, is one of the few wheat cultivars with resistance to scab. The expression pattern of lipase gene has been studied during wheat defense reaction to fungal extract, spore suspension, toxin (DON) and salicylic acid treatments in Scab-tolerant (Sumai3) and scab-susceptible (Falat) wheat cultivars. Infected spikes are sampled during 0, 3, 6, 12, 24, 36, 72 hours and 7 days after artificial inoculation and subjected to total RNA extraction and cDNA synthesis. Quantitative Real-Time PCR was performed with specific primer to detect expression differences between tolerant and susceptible cultivars. Output data was analysed using REST software, indicated differences in expression level of cultivars during disease expansion cycle. We compared result from four expression pattern against different treatment for obtain the role of lipase gene in SAR cascade. Particulary observed aggregation of lipase transcripts in 6 hours to 7 days against F. graminearum spores suspension and they increased in 24 to 7 days against fungal extract in resistant variety. Also lipase transcripts increased in 6 and 72 hours against DON treatment in resistant variety. These increases observed whereas accumulate of lipase gene decreased in susceptible variety. This evidence can use for discover the SAR element in systemic reaction and can be base of other similar experiment to clear this mechanism.