温度和处理时段对西瓜四倍体诱导的影响及其倍性鉴定

Effects of Temperatures and Day Times Treatments on Tetraploid Induction and Its Ploidy Identification in Watermelon

以3个不同熟性西瓜为诱导材料,幼苗两叶一心时摘心后,用秋水仙素滴苗,以不同温度及不同时间段进行处理研究对四倍体的诱导。结果发现,西瓜幼苗的成活率和诱导率因不同品种、处理温度和处理时间而异。幼苗摘心后处理的温度越低,成活率越高,随之诱导率也越高,在29℃时幼苗的成活率和诱导率高于32℃和35℃。不同时间处理对不同基因型的成活率和诱导率虽不同,但均是在每天的17:00-18:00处理时最高。四倍体西瓜的叶片和花器官比二倍体的大,颜色较深。叶片的保卫细胞的长度和叶绿体数目随倍性的增加而增加。采用改良品红压片法能够清楚地鉴定花粉母细胞染色体数目,是可靠的鉴定方法。

Three watermelon materials were employed to establish the technical system of tetraploid induction by using colchicine treatment method with different temperatures and different period. The results showed that the rate of survival and induction of tetraploid in watermelon plants depended on different cultivar, treating temperature and treating time. The lower the temperature was, the higher seedling survival rates were, as well as the induction rate. The rate of survival and induction both were the highest at 29℃. At the different treating day time ,the rate of survival and induction of the three genotypes were different, but their induction rates were the highest at 17.00--18：00 every day. Tetraploid of watermelon was characterized by lager leaves and followers with deeper color than that of diploid. The guard cell length was longer and the No. of chloroplast guard cell were increasing with polyploidy in leaf cell. The polyploid identification was carried by using carbo fuchsin method in pollen mother cell,which was the most reliable method in the polyploid identification.