Fundamental study for citrus chromosome mapping

点击翻译按钮获取中文摘要

Major purpose of this study is to develop new chromosome preparation method for citrus karyotype analysis that is important of gene chromosome mapping, and the second is to try citrus karyotype analysis using this new method and to develop useful chromosome banding method for identification of citrus chromosome.1.Optimum enzymatic treatment was 120 min.incubation of 2% cellulase + 1% pectolyase or 90 min.incubation of 3% cellurase + 2% pectolyase for root tip of in vitro cultured plantlet, and 90min.incubation of 3% cellurase + 1% pectolyase for young leaf tip from orchard tree. The chromosome length of the longest one in each chromosome setreached 4-10mum that was over 2-5 times of the longest chromosome length which had been reported.2.The chromosome numbers of 2n=18 in Poncirus and orange, 2n=20-21 in 'Tosa-Buntan' and 'Suisho-Buntan', 2n=19 in satsuma mandarin, 2n=20 in Fortunella and 2n=19-20 in yuzu were major in this investigation. The karyotyape analysis of Poncirus and orange indicated that both had 2 pairs of metacentric and 7 pairs of submetacentric chromosome, and 6 paires of Poncirus chromosome and 5 pairs of orange chromosome were possible to be identified.3.G banding and N banding method was not available for citrus chromosome. C banding method showed unique banding pattern but repeatability was very low in the present study. CMA/DAPI stain showed stable unique band in 'Tosa-Buntan' chromosome. There were 3 types of chromosome that having 2 bands, 1band and no band.