The Application Of SSR Molecular Markers In Variety Purity Identification Of Hybrid Rice

Hybrid rice seeds of eight varieties (Nei5You8015,Y Liangyou689, II You7954,Q You1,ZhuLiangyou06, Zhe you12, Zhe you18, Chun you84) were separately collected from5seed productionareaes (Shanghai, Jiangxi, Hainan, Guangxi, Jiangsu). These seeds were used to investigate theapplications of SSR molecular marker in purity identification of hybrid rice seeds. The mainconclusions were drawn as follows.1. The rapid DNA extraction conditions of rice seeds were explored and the key steps wereoptimized in the original extraction method. The optimal DNA extraction conditions of different hybridrice varieties were described as follows:12h was the optimal soaking time for Nei5You8015, II You7954, Q You1, Zhe you12, Zhe you18while20h was the optimal for Y Liang you689, Zhu Liang you06and Chun you84; In addition,15min was the optimal centrifugal time of seed extracts in the firstcentrifugation.2. The original PCR reaction system was optimized and the optimal PCR reaction systems for eightvarieties were ascertained. PCR reaction system (10μl) of Nei5You8015, II You7954, Q You1, Zheyou12, Zhe you18:5μl Mix,1μl DNA,0.25μl Forward primer,0.25μl, Reverse primer,3.5μl H2O.PCR reaction system (10μl) of Y Liang you689, Zhu Liang you06, Chun you84:5μl Mix,1.5μlDNA,0.25μl Forward primer,0.25μl Reverse primer,3.5μl H2O.3.24pairs of primers recommended by National DNA Fingerprinting Indentification Method forRice Cultivars were used for PCR amplification. The effective primers for each variety were screenedand the corresponding standard fingerprints were constructed. The average purity determined by thestandard fingerprints of Nei5You8015, Y Liang you689, II You7954, Q You1, Zhu Liang you06,Zhe you12, Zhe you18, Chun you84was96.3%、97.6%、96.3%、96.1%、96.9%、98.6%、98.2%、97.1%.4. Field plot identifications were conducted in Shanghai, Jiangxi, Hainan, Guangxi, Jiangsu. Thetypical traits of plants of8hybrid varieties were observed from seedling stage to maturation stage.Theaverage purity determined by the field plot identifications of Nei5You8015, Y Liang you689,II You7954, Q You1, Zhu Liang you06, Zhe you12, Zhe you18, Chun you84was97.7%、98.4%、98.3%、97.7%、98.0%、98.9%、99.0%、98.0%. 5. Some conclusions could be drawn from the above results. Purity determined by SSR method wereslightly lower than that by field plot, suggesting that SSR molecular markers were easier to differentiatefalse seeds while field plots were difficult to characterize false plants. Statistics analysis showed thatthere were no significant differences between the results determined by SSR method and those by filedplot. In general, SSR molecular marker method could be used for the rapid identification of seed purity,which is significance for seed companies to acquaint the status of seed quality and sell them earlierly.