Studies on chromosomal ploidy of somatic polyploids of Hevea brasiliensis
Chromosomal ploidies of somatic polyploidy clones Haiken-2 and PR107 (Hevea brasiliensis) induced with colchicine 16 years ago have been studied with their diploidy parents as control. Results showed that these polyploidy clones were composed of numeral sorts of chromosomal ploidy cells with plyploidy cells being dominant. Between polyploidy trees or parts of the same tree, the proportions or mosaic degrees of various ploidy cells are evidently different. After 16 years of growth, the triploidy cells in rubber polyploids have been increasing evidently while tetraploidy ones decreased drastically. It seems that the tetraploidy cells tend to be transformed to the triploidy. The cells between parent trees or part of the same parent tree are mostly of chromosomal diploidy and not obviously different in chromosomal ploidies.