Study Of Paclobutrazol To Improve Embro Rescue Of Seedless Grape

Because of unique advantages,seedless grapes are widely welcomed by consumers.In this study,stenospermocarpic seedless grapes were chose as female parents,some wine grape varieties were chose as male parent,12 hybrid combinations were set up.On the basis of previous studies,we tried tofurther study the genotypes,sampling time,exogenous use of paclobutrazol on embryo rescue,so as to optimize embryo rescue technology.At the same time,we further classified the deformed seedlings in the process of embryo rescue,and transformed them in order to find a suitable transformation medium,thus to improve the utilization of the deformed seedlings,which will provide the basis for improving the efficiency of embryo rescue.The results of our study are as follows:1.The influence of parental genotypes on embryo rescue.Seedless varieties such as Flame Seedless,Kunxiang Seedless,Fantasy Seedless,when chose these varieties as female parents showed high germination rate and seedling rate,but on the contrary Crimson Seedless and Thompson Seedless were not suitable as female parents.The selection of male parents also had impact on the embryo rescue.When chose Flame Seedless as female parent,Muscat and Beibinghong as male parents,Muscat was better than Beibinghong.When chose Kunxiang Seedless as female parent,Taishan-2 and Beibinghong as male parents,Beibinghong was better than Taishan-2.When chose Fantasy Seedless as female parent,Shine-Muscat,Shuangyou,and Beibinghong as male parents,Shine-Muscat and Shuangyou were better than Beibinghong.2.The effect of exogenous use of PAC on embryo rescue.In the stage of ovule development,chose MM3+1.5mg/L PAC could increase the embryo formation rate.The embryo formation rate of cross Flame Seedless×Beibinghong reached 23.33%,and Kunxiang Seedless× Taishan-2 reached 53.33%.When adding 1?mol/L PAC to the basic medium WPM during embryo germination could increase the germination rate and seedling rate.The germination rate and seedling rate of cross Sultanina Rose×Beibinghong reached 70% and 35% respectively,and the seedling rate of Sultanina Rose×Kunxiang Seedless was 40%.3.When use stenospermocarpic seedless grapes as female parents,the best sampling time of each cross was different.For the sampling time of cross Flame Seedless Seedless ×Muscat,39 days after pollination(DAP)was better,46 DAP was suitable for cross Kunxiang Seedless×Beibinghong,40 DAP was proper for cross Fantasy Seedless×Shine-Muscat,41 DAP might be proper for Ruby Seedless×Beibinghong and Fantasy Seedless×Shuangyou.4.There always were malformed seedlings during the process of embryo rescue,when they were inoculated to the transformation mediums,some of them would grow into normal seedlings again.When inoculating malformed seedlings of cross Flame Seedless Seedless ×Muscat to basic medium WPM,added with 0.2 mg/L IBA showed the highest transformation rate,reached 16.67%,but for cross Kunxiang Seedless×Beibinghong,when the malformed seedlings inoculated to basic medium WPM added with 0.5 mg/L IBA showed the highest transformation rate,reached 40.09%.5.14687 ovules were inoculated in total,1855 embryos were excised,1089 embryos germinated and 450 lines were obtained,the seedling rate reached 3.06%.706 seedlings were hardening off after secondary culture,and 628 seedlings were survived,the survival rate reached 88.95%.In 2017,240 seedlings were survived in total when transplanted 288 seedlings into fields and the survival rate of transplant reached 83.33%.