Reserch On The Optimization Of The Microspore Cultivation System And The Technology Of Plant Regeneration In Cabbage(Brassica Oleracea L.)

The research was explored the effect of microspore culture,regeneration of non-cotyledon embryogenic and formation of adventitious buds to improve the differentiation rate of adventitious bud from non-cotyledonous embryos,enhance the growth potential of DH plants and speed up the breeding process of cabbage DH plant.The effects of pruning,melatonin（MT）,p-chlorophenoxyisobutyric acid（PCIB）and arabinogalactan（AG）concentration on induction of embryos,different ratios of KT and NAA,PCIB and AgNO₃ concentration on regeneration of non-cotyledon,and MT and NAA concentration on regeneration of adventitious buds from cabbage embryoid were studied.The results were as follows:1.The shoots retained 20%,50% and 80% of the first branch increasing the rate of microspore in the late uninucleate stage and the embryos when the plants bolted.Compared with the control plants in the natural state,the rate of microspore in the late uninucleate stage,embryos and cotyledon embryoidwere respectively increased by 122.3%,3.2 embryos/bud and 0.77% whileshoots retained 50% of the first branch.2.The addition of MT,AG and PCIB in NLN-14 medium of microspores culture significantly improved the induction effect of embryoid.The optimum concentration was different among different materials.The highest rate of embryos was 19.5 embryos/bud at MT concentration of 1.0 μmol/L in precocious materials Xinlvzhou,reached 9.8 embryos/bud at AG concentration of 20.0mg/L in middle materials C64 and 18.5 embryos/buds at PCIB concentration of 40 μmol/L in early-maturingmaterials C69.3.The differentiation rate of adventitious buds of material Hui 2 in NLN-14 medium reached the maximum value 26.67% with 1.0 mg/L KT and 0.02 mg/L NAA,and 16.67% with 40μmol/L PCIB.The addition of 2¹0 mg/L AgNO₃ was not conducive to greening for non-cotyledon embryo,but the suitable concentration could promote green embryo to form adventitious bud.4.The addition of 5 μmol/L MT and 0.1 mg/L NAA in the MS medium of the adventitious buds could significantly take root and rapidly grow in DH plants including the DH-A,DH-B and DH-C.,but difference was not significant.The bolting rate of DH-A,DH-B and DH-C in the following year was respectively increased by 33.4%,20.0% and 20.0%.