Studies On The Activities Of PAL,PPO And POD Of The Grafted Balsm Pear Seedlings And Their Effects Of Cultivation

The cleft grafting,approaching and cutting grafting were applied in grafting Bixiu balsm pear on Shuanyi luffa in this study. The survive rate, activities of POD, PPO and PAL and yield between grafting seedlings and seedling from seeds, the ability of resistance against flood and Fusarium oxysporum, effects of low and high temperature on yield also were studied. The results are as following:1. Among cleft grafting, approaching and cutting grafting, approaching had higher survive rate than others when scions with 2 leaves, but it cost too much and had a complex process. In contrast, cleft grafting is a better grafting when seedling with cotyledon only, the survive rate was up to 95.7% that just lower 6.1% than approaching.2. The activities of POD, PPO and PAL of grafting seedlings were higher than seedling from seeds'.3 After inoculated, the activity of PPO raised highly and it was 8 times higher than non-inoculated. But POD became lower and PAL's activity raised.4 The seedlings form seeds suffered from Fusarium oxysporum badly and senesced early. Then, the grafted seedlings were harvested earlier and the period of harvest lasted almost one month longer than seedlings form seeds did.5. In adversity, the ions change less in grafted seedlings. In the low temperature, the conductance became higher in both grafted seedlings or not, but seedlings form seeds were harmed more badly than grafted seedlings. All the above showed that besides the concentration of ions, rootstocks contributes to the resistance. The activity of POD,PAL,PPO of grafted seedling were higher than seedling from seed when they flooded or not, and the enzyme activity of grafting was not signified. So the grafting was higher ability of resistance than seedling from seed.6. In 2007, the grafting was applied mainly widely in Sichuan and the area was more than 1.3×10~7m~2. So grafting became the main cultivation method.