Study On Micro Propagation Of Walnut

Walnut (Juglans regia L.) originated from southeast of Europe and west of Asia, China is one of walnut original habitats. The walnut is the fine economical arbor and regarded as one of the four dried fruits in the world because of the fruit and lignum uses. It was cultivated widespread in the world because of its economical, ecological and social efficiency, but there are many difficulties in extending of the superior walnut varieties.During the propagation of walnut tissues, the chosen explants appears to high pollution rate, the walnut buds turning brown serious, low reproducibility of the next generations, the seedling taking little and weak roots as well as the micro-grafts as the graft methods leading to the low survival rate and so on, this paper has studied that different walnut tissues as the explants, the factors inducing the walnut somatic cell become embryo and micrografting technology. Test result as follows:1.1 The most suitable medium in primary culture is DKW+6-BA1.0mg/L+IBA0.1 mg/L+Vc5.0 mg/L+ agar 6.0g/L+ sugar 30 g/L.1.2 Selecting material from the middle of May to the first ten days of June, the pollution rate are lower than 5%, approached to 3.1%; Selecting material in May and in August could reduce the browning rate, and reach the lowest in August. The rate is 25.64%.1.3 The browning rate of 8-week-old seedlings directly from seed is only 17.2%, one-year-old is 26.3%, but the grown-up trees reach 48.5%.1.4 The antioxidant and sorbent test result indicated that Vc5mg/L might make browning rate the lowest (8.87%).1.5 The test results of continuative cultivate indicated that the most effective concentration of 6-BA is 1.0 mg/L and the corresponding concentration of IBA is between 0.01-0.05 mg/L. Cultivation of lustihood for the test-tube plantlet test result indicated that the DKW culture medium attached 0.25 mg/L6-BA and 0.03 mg/L IBA is the most suitable culture medium. The suitable transfer cycle is 25~30d. The most suitable pH for the growth and the multiplication of the walnut test-tube plantlet is 5.8.1.6 The suitable culture medium for radication is 1/2DKW+IBA3.0mg/L+ 2.0g/LAC+...