Abstract
The tea cultivar Sayamakaori bred for the production of Japanese green tea is resistant to Kanzawa spider mites and mulberry scales and is tolerant to low-temperature and frost stress. Thus, Sayamakaori is a very important breeding material for resistance and tolerance in the breeding of tea plants. This cultivar was selected at Saitama Prefectural Tea Experiment Station from natural crossing of seeds harvested from a tea cultivar Yabukita at Shizuoka Tea Experiment Station in 1947. Sayamakaori has very specific traits that are absent in Japanese original teas, for example extremely upright leaves, dark green leaves and so on. It has been reconfirmed that each individual in the F1 progeny had inherited these traits from Sayamakaori, which indicates that the traits of Sayamakaori are controlled by genes with dominant effects. Since Yabukita does not have the traits specific to Sayamakaori, it was assumed that the pollen parent should exhibit these traits. Therefore, 78 clones were screened as putative pollen parents of Sayamakaori in the field of Shizuoka Tea Experiment Station. All the 78 putative pollen parents were introduced from abroad, mostly from China, not including the Japanese original clone. The parentage test using DNA markers was performed between Yabukita and the putative pollen parents, and no clone was found to be the pollen parent of Sayamakaori. Therefore, the pollen parent of Sayamakaori may not exist presently.
