Resumen de A series of polyploid grape cultivars and their structural identification of ploidy character
X. P. Tang, J. Chen, X. H. Ma, Zheng-Dong Wang, F. Q. Zhao, X.M. Li, W. Tan
A series of new polyploid grape cultivars were bred using the strategy which combines traditional cross breeding with chemical-induced variation. In this strategy, germinated diploid hybrid grape seeds were treated with colchicine 0.6% at 25°C during the day and 20°C during the night for 48-72 h then planted in the field. The treated hybrid seedlings were first examined morphologically and then analyzed by tip-end slicing to verify the ploidy structure of the meristematic cells from the LI and LII layers. Results from chromosome counting in root tips indicated that these descedants are 2n=4x=76 while their parents are 2n=2x=38. Based on the size and shape of pollen and stomata, the number of chloroplasts in guard cells, it was concluded that these grape cultivars are tetraploids. Three tetraploid cultivars named ?Zaoheibao?, ?Qiuheibao? and ?Wanheibao? were generated using this strategy, maturing at early-season of August, late-season of August and late-season of September, all have black purple in color, ?Muscat? flavor, good adaptability to environment and high disease-resistance.
