| 7 crosses between seedless grapes and Chinese wild Vitis ,6 crosses between seedless grapes were carried out from May of 2002 to May of 2003 in order to obtain new grape germplasms of seedless and disease resistance.The effects of sampling dates,basic medium,culture environment on embryo rescue were studied.The plantlets converted from embryo rescue were transplanted and established on the vineyard .In 2004,plant growth regulators:chlormequat,BAP,putrescine,ethephon,appending nourish-ment ,were evaluated at different concentrations and times by spraying berries for promotion of ovules development and plants convertion of three stenospermocarpic grape cultivars(Vitis vinifera L.):"Centennial Seedless","Thompson Seedless"and "Crimson Seedless".The results were as follows: 1. 322 embryo rescue seedlings were obtained from 13 crosses,including 257 seedlings from 7 crosses of seedless grapes×Chinese wild Vitis,65 seedlings from 6 crosses of seedless grapes×seedless grapes.Progenies of hybrids of seedless grapes×Chinese wild vitis including 17 new seedlings from Delight(V.vinifera L.) ×Jiangxi-3(V.hancockii Hance),18 seedlings from Delight ×Jiangxi-2 (V.romanetii Roman.),114 seedlings from Delight ×Shuangyou(V.amurensis Rupr.),32 seedlings from Olmo Seedless(V.vinifera L.) ×Taishan-2(V.adstricta Hance), 26 seedlings from Olmo Seedless ×Gansu-91 (V.piasezkii Maxim.), 15 seedlings from Flame Seedless(V.vinifera L.) ×Pinli-5 (V.qinlingensis P.C.He), 35 seedlings from Flame Seedless ×Heilongjiang Seedling (V.amurensis Rupr.).The percentage of seedlings convertion of embryo rescue differed significantly among crosses. The percentages of seedlings convertion in the crosses of regarding Delight,Olmo Seedless and K????? X????y as female parent seperately were greater.Of Delight ×Shuangyou, the percentage(24.48%) of embryo development was greatest, the percenage of seedling obtainment was 10.86%. 1471 plants of 255 strains were transplanted,601 plants of 211 strains survived from nursery,the percentage surviving from greenhouse and nursery were 67.0% and 83.9% respectively.The survived plants from nursery were established on the vineyard in spring of 2005. 2. The system of embryo rescue was optimized.The effect of different sampling dates to embryos development in a few crosses was studied.Of Delight×Jiangxi-3,the greater percentage of embryo development was obtained by cultured in 58 day than in 50 day after pollination.Of K????? X????y ×Flame Seedless,the effect on embryos development is similar to cultured in 58 and 54 day after pollination.Of Black Monukka ×Centennial Seedless ,the result of embryos development in 54 day is better than in 52 day.Of Flame Seedless ×Heilongjiang Seedling,the result in 50 day is better than 46 day.It was showed that the greater percentage of embryo development was obtained by cultured in the later date during the limited period.The effect of medium and culture environment to embryo rescue was studied.As a result,The greater percentage of embryo development was obtained on ER liquid medium in polycarbonate petri dishes cultured in dark during the stage of ovules development.The addition of 2～5 m mol/L putrescine to ER medium promoted the ovules development of "Delight".While during the stage of embryos germination,1/2MS solid medium supplemented IBA or IAA 0.1～0.2 mg/L with test tubes using as culture vessels and in light environment was preferable.Embryos transferred in germination medium could be converted into plants directly.This was an advanced system because it eliminated the step of transferring convertion medium and simplifed the embryo rescue procedure. 3.The preliminary method was investigated to promote stenospermic grape ovules development with plant growth regulator.The studies were conducted on "Centennial Seedless","Thompson Seedless"and "Crimson Seedless".Treatments consisted of four plant growth regulators(chlormequat, BAP, putrescine, ethephon) appending nourish-ment applied at two different concentrations each,once and twice applied each and three controls,for a total of 19 treatments.The plant growth regulators had no effect on ovules number of per berry.No evidence indicated that the nourishment could stimulate ovule development. The ovule weight and percentage of ovules upper grade 2 of"Centennial Seedless","Thompson Seedless"and "Crimson Seedless"were increased by sigle applied at two weeks pre-bloom and double applied at pre-bloom and post-bloom of 100～1000 mg/L chlormequat.With the treatment of 1000 mg/L chlormequat double applied,the weight and big size ovules percentage increased signifinantly compared to controls in maturation,moreover,the increasing was observed in 50 and 60 day postbloom.The increasing was also significant in maturation and 50 day postbloom of"Crimson Seedless"compared to control.The effect of 100 mg/L BA and 20 mg/L putrescine showed that ovules development of"Centennial Seedless","Crimson Seedless"were promoted.Ethephon had no effect on development of ovules.Treatment above increased the percentage of developed embryos by means of promoting the development of ovules,as the result,raised the percentage of plant convertion.The ovules were biger,the percentage of embryo development was greater.Moreover,the embryos were biger,the percentage of embryo germination was greater,the embryos of primarier than globular stage didn't germinate. |
