Analyzing the Ploidy Levels and Seed Setting Character of Microspore Regenerated Plants in Rapeseed

This study was to investigate the genotypic difference in ploidy levels of microspore-derived plants and the effect of colchicine treatment on seed setting of the regenerated plants in oilseed rape.After measuring the ploidy levels of young plantlets by Flow-cytometry(FCM),the diploid/haploid mixed and haploid plantlets were treated with 0.5 mg.mL-1 colchicine,then chromosome doubling efficiency and seed setting characters were investigated.The results of FCM detection showed that 20-28% of regenerated plants were spontaneous doubling haploids,in which,60-80% was developed to be normal diploid plants.The majority of regenerated plantlets showed ploidy levels with the diploid/haploid mixed(45%-60%) and only 7% of them could harvest seeds from full fertile plants,but after artificially doubling treatment,the total number of productive plants was significantly increased from in average of 40% to 75%,however,most of them were partial diploids(diploid/haploid mixed).Our results demonstrated that the spontaneous doubled haploids clearly showed more pods per plant and longer pod length with more seeds number than that of diploid plants induced by colchicine treatment,while the colchicine treatment significantly promoted their pod formation and development,with an average of 1.2cm increase in pod length and 4 seeds more per pod.