Observation Of Microspore Development And Studys On High Embryo Rates Induction Technique Of Microspore Culture In Cabbage (Brassica Oleracea. Var.capitata L.)

Isolated microspores culture technique applied to plant genetic and breeding widely because researchers can attain valuable double haploid for breeding by the technique with shorter time and higher efficiency. On the other hand, the embryoid and regeneration plantlet of isolated microspores culture are used to The construction of genetic map, gene direction, trans-gene breeding,chromosome engineering, and so on.Pollen from 11 genotypes of cabbage was cultured. The effects of cabbage genotype and affecting factors were analyzed on isolated microspore culture, meanwhile , using Qingan80,8398 for materials , factors were studied that had effects on induction culture of cabbage ,such as bud length, sucrose concentration,low temperature pretreatment , high temperature treatment , hormone and colchicine.The results showed that:1. The suitable sampled bud is different for different genotype hybrids. For most varieties, the range of buds with 4.5~5.49mm length is optimal for isolated microspore culture of cabbage. Choosing the buds of the microspores which are round and have three sag are proper while inoculation.2. Genotype was main factor that had an effect on success in cabbage pollen culture. It was significant difference in induction rate of pollen culture. Of the11experiment materials, 5 genotypes produced embryoids. Among them, 2 lines (Qingan80, and 8398) produced higher embryo yield. In addition ,the other 6 materials (WG03,Lvqiu66,Qingan60,0268,FW25,FW02)could not gain embryoids no matter what methods to take3. The optimal sucrose content is 13% for isolated microspore culture of cabbage, and the 17% is helpful to maintain the microspore viability.4. Low temperature pretreatment and proper high temperature was important factors for increasing induction rate of microspore culture. Low temperature pretreatment had a significant effect for embryoid yield, different genotype had different pretreatment time .All the materials microspore embryoid yield had significant improvement under low temperature pretreatment. The treatment that buds were pretreated with 4℃low temperature during 24 hours before microspore cultured and microspore were cultured darkling with 33℃high temperature during 24 hours at initial stage , could obtain better inducing result.5. Hormone had important affect roles on microspore induction culture, but different genotypes had different effect to hormone. According to contrast of addition hormone 6-BA and NAA five concentration proportions in the NLN-13 fluid medium to process microspore induction embryoid culture. 8398's embryo rate was 4.85embryo per bud under no hormone medium, higher than other hormone concentration treatment medium. Qingan80's embryo rate was 6.20 embryo per bud under single addition hormone 6-BA0.05mg/l and higher than all other concentration treatment medium.6. The results of ck are better than other treatments which contains colchicine.