Objective Genetic information on Camellia sinensis hybrids generated by crossing two existing cultivars was studied to facilitate further breeding and resource utilization.
Method Agronomic traits and genetic diversity of 18 tea germplasms developed by crossing between Ruixiang and Baijiguan Teas were determined and analyzed using SSR markers.
Result (1)The 18 hybrids were genetically varied with differentiated agronomic characteristics. For instance, being shrubs with semi-open or open posture like the others, BJG10 and RX6 differed from the rest by having small rather than medium sized leaves; RX3, RX4, and RX7 had the one-bud-and-one-leaf stage started more than 7 d earlier than control (‘Huangdan’); and RX2, RX3, RX6, and RX7 had elliptic leaves while most of F1 hybrids showed long elliptically shaped leaves. (2) A total of 150 polymorphic loci were detected in 20 pairs of SSR markers of the germplasms with an average of 7.500 alleles. The Shannon indexes averaged 1.356, and the observed and expected heterozygosity, 0.634 and 0.632, respectively. (3) The similarity coefficient clustering on BJG6 through BJG10 showed a close relation among them, as well as with 'Mingke 1' (Jinguanyin). The genetic relationship between RX5 and RX7 were relatively close and largely inherited from the maternal 'Ruixiang' Tea.
Conclusion Genetically, the 18 hybrids of Ruixiang and Baijiguan Teas were closely related but richly diverse.