Research Of Embryoid Sac Regeneration Plants Induction By In Vitro Culture Of The Female Nucleus In Cucurbita Pepo L.

Female nucleus in vitro culture is an important way for creating new breeding resourcesin Cucurbita pepo L. This experiment studied unpollinated ovaries and unfertilized ovules invitro culture on six varieties materials of Cucurbita pepo L. Mainly discussed the influence ofembryoid induction on the hormone type and concentration, cultivation season, the treatmentperiod and the time of the ‘fruit setting king’, the female flower node, ovule cutting methodsand other factors. The domestication transplanting experiment was carried out to improve thesurvival rate of regeneration plant embryo.1. Adding TDZ in MS medium was better than adding6-BA and NAA combination effect.And the most appropriate medium for embryoid induction was MS+30g·L-1Suc+8g·L-1Agar+0.06mg·L-1TDZ. The highest induction rate of unpollinated ovary embryoid wasautumn cultivation, followed by summer mountain cultivation, and the lowest induction ratewas spring cultivation.2. The embryoid induction rate of unfertilized ovules which ovaries processed by the‘fruit setting king’ on the flowering day and one day before flowering were significantlyhigher than on one day after flowering. The highest induction rate was the flowering dayprocessing. In addition, unfertilized ovules treated fourteen days by the ‘fruit setting king’ hadthe highest embryoid induction rate. The embryoid induction rate of middle node femaleflower was up to8.13percent which was significantly higher than that low and high femaleflower node. The high female flower node was a bit difficult to induce embryoids. Theinduction rate level of unfertilized ovules showed a trend that cross cutting> slitting cutting>beak cutting> full ovule. The crosscutting ovule culture embryoid induction rate was up to9.65percent.3. It can been seen that most of the embryo sacs were in the eight nuclear period on theflowering day according to observing the ovary paraffin sections of Cucurbita pepo L.Ovaries on the flowering day were most suitable for embryoid induction.4. MS+30g·L-1Suc+8g·L-1Agar+0.5mg·L-1GA3medium was suitable for embryoids’ root regeneration. Adding GA3in MS medium had an advantage in rooting rate, rooting timeand rooting quality than NAA. The best period for regenerated sac plants domesticating andtransplanting was5～6leaves period, and the survival rate was up to90.0percent.5. Five in forty sac plants were identified haploid according to root tip chromosome count.The haploid rate was12.5percent.