Use Of PCR-RFLP Markerto Detect P.capsici In Squash

The 18s rDNA from the 14 isolate of 12 species of pathogenitic fungus were amplified by using a pair of special primers, and then the amplified production of PCR was digested by 4 kinds of restricted enzymes (EcoR I HaellI Hha I Hinf I). The DNA抯 polymorphism among these isolates was also analyzed. At last we detected the P capsici from disease squash by using the PCR-RFLP detection program. The results are following.I)By using a pair of special primers, all the Phytophthora isolate can be amplified to form a special fragment of I 770bp.2)Being digested by 4 kinds of restricted enzymes and being analyzed by the cluster. the 3 P capsici isolates from the different host of parasite have been proved to be no difference in heredity.3)A special DNA fragment of I 770bp has been gained from the leaves which have been inoculated for 12 hours at the symptom and health border of the stems, leaves and fruits of the disease squash.4)Being digested by the restricted enzymes, the special fragment possesses the completely same restriction fragment patterns with the P. capsici, which is the purpose of detection. The experimental result is valuable for diagnosing the disease early and disease forecasting.