Plant Regeneration Method Of Unfertilized Ovule Of Pumpkin

Promotions of life quality encourage consumers to expand the demand of the pumpkin.But in our country, it is difficult to reach the level of people’s demand because the pumpkin breeding started late, the germplasm resource materials was few, and the breeding speed was slow. Haploid culture technique can quickly obtain pure lines, shorten breeding period.Previous studies have indicated that it is very difficult to induce the regeneration of pumpkin anther, so the study on the regeneration system of the female nucleus of the pumpkin has important significance. The research used ‘Beilihui’ as experimental materials to study the induction of plant regeneration from pumpkin unfertilized ovules. This experiment mainly through the research on different pre-processing, exogenous additives, different ovary slice thickness to select the optimum conditions of ovules swelling and turn green. Through the study of hormone concentration and the ratio of hormones to select the best medium of pumpkin embryogenic callus induction. Through the research of the regeneration method of pumpkin cotyledon node to find out the bud regeneration medium. Lay the foundation for the study of the regeneration plant of pumpkin unfertilized ovules. The main results were as follows:1. Screening of pumpkin unfertilized ovule expanded and turn green medium:(1) Only adding TDZ in the culture medium can significantly increase the rate of the expansion of the ovule on the pumpkin ovary and the sensitivity of the pumpkin to the low concentration TDZ was similar.(2) Adding 4.0 mg·L-12,4-D+1.0 mg·L-16-BA+0.5 mg·L-1NAA(F2), the induction ratio was the highest and the effect of the expansion of the green was better than TDZ.(3)Ag NO3 was 30mg·L-1, the ovules growth rapidly, deep green, and ovule volume was significantly greater than F2 and the induction rate was 100%. The test results shows that the best culture medium for pumpkin unfertilized ovule expanded and turn green medium:MS+0.05 mg·L-1TDZ+1.0mg·L-16-BA+0.5mg·L-1NAA+30mg·L-1Ag NO3.2. At the ambient temperature of 35℃,dark heat treatment 5d, the fertilized seed of the pumpkin was expanded and turned green.3. Addition 4mg·L-1of KT to pretreatment medium and treatment for 2d was conducive to the ovules swelling and turn green.4. The optimum thickness of the pumpkin unfertilized ovary slice was 1.0mm.5. The most suitable culture medium for the induction of callus from the pumpkinunfertilized ovules was MS+1.0mg·L-16-BA+0.5mg·L-1NAA and the induction rate was68.33%.6. Adding 1.0mg·L-16-BA and 0.02mg·L-1IBA in culture medium, pumpkin cotyledons of adventitious bud induction rate was 66.67%, than adding 2mg·L-1and 3mg·L-1KT can significantly improve the induction rate to 100%.