Relationship between the number of tapping-induced secondary laticifer lines and rubber yield among Hevea germplasm

The lack of suitable early selection parameters means that traditional rubber breeding for yield is timeconsuming and inefficient. Laticifer is a tissue specific for natural rubber biosynthesis and storage in rubber tree. The number of the secondary laticifers in the trunk bark tissues is positively correlated with rubber yield in the matured rubber trees that are regularly tapped. In the present study, the rubber yield from 280 of 4-5 year-old virgin trees from 7 cross combinations was compared with the number of newly differentiated secondary laticifers caused by tapping. Results showed that the number of tappinginduced lines of secondary laticifers varied in different germplasm and was positively related to the rubber yield, indicating this could be used as a suitable parameter for early evaluation of yield potential of rubber trees.