Variation in yield among competing individuals within mixed genotype stands of tea: a selection problem.
Abstract
The procedure adopted in an attempt to identify bushes which would produce high-yielding clones is described. In a six-month study in Kericho, Kenya, bushes with strongly inherited leaf colour were found to be distributed randomly in the plantation and it was assumed that bushes with any specific genetic trait would be also. Statistical analyses indicated that nongenetic between-plant competition and site heterogeneity masked inherent differences in yield of two stands of mixed Assam and China genotypes. Individuals which performed better than expected compared to their neighbours were selected. Patches of fertile soil were identified by clumps of bushes with a high mean yield per unit bush surface area. Any provisionally selected bushes which occurred within these clumps were eliminated. The remaining selections were propagated vegetatively in 1976 for further study.