Effectiveness of assessment of vigour and productivity in young vs old bushes and mature clones of tea (Camellia sinensis)

Summary The effectiveness and validity of assessment of bush vigour as expressed by bush area, shoot number and yield in selecting for high yielding clones in tea was tested by comparing the field performance of 50 source bushes when they were 4 yr old in 1977/78 with that of the same bushes when they were 13 yr old in 1986/87 and also with that of the 8 yr old vegetatively propagated plants (clones) derived from them and transplanted to the field in December 1979. Apparently vigorous bushes produced the highest yield. The three characters measured in mature source bushes and, to a lesser extent, clonal derivatives were positively correlated with measurements in young source bushes. Seven of the best yielding source bushes and five of the best clones in 1986/87 were present in the 10 highest yielding source bushes identified in the 1977/78 season. Assessment of bush area and shoot number was confirmed as an effective and valid method of identifying a small, highest yielding group of source bushes from a large population of seedling tea which should go for rooting assessment and further more thorough screening of yield.