Yield repeatability and evaluation period in hybrid cocoa assessment

Abstract

Repeatability estimates were obtained from an experiment carried out in Rondônia state to define theevaluation period necessary to discriminate between cocoa hybrid yields. Data collection involved these traits:total number of fruits harvested (TNFC), total number of healthy fruits (TNHF), total weight of fresh seeds(TWFS), mean weight of fresh seeds per fruit (MNFSF), percentage of wasted fruits (SPWF) and percentage ofwasted fruits due to witches’ broom disease (PWFWB). Repeatability estimates were high for the two last traits(values above 0.8) but were relatively low (lower than 0.65) for the others when the ANOVA estimation wasperformed on data collected at maturity. These estimates indicated that three evaluations are necessary from the8th year after planting for efficient selection (accuracy > 70%) for all the assessed traits. When the average of theassessments carried out in two pre-climax years was considered, it was possible to obtain a correlation greaterthan 0.70 between the real hybrid value and the traits total number of fruits collected and percentage of wastedfruits.