Genotypic Performance of Cocoa CTheobroma cacao L.) during Establishment under Natural Drought Stress

摘要

Forest areas traditionally used for cocoa cultivation are severely stressed, leading to increased mortality in cocoa seedlings during establishment. The objective of this study was to evaluate the drought response of cocoa genotypes under different field establishment stresses during the dry season. A field experiment was conducted in ‘shade’ and ‘no-shade’ by using a split-plot design, with watering and no-watering treatments as main-plots and cocoa genotypes as subplots under natural drought stress. The following traits were measured: stem growth, leaf chlorophyll content, vigor, and percentage survival. The genotype x water treatment interaction was significant (P = 0.05) for stem growth and percentage survival both in shade and no-shade, whereas it was significant (P = 0.05) for vigor only in no-shade and for leaf chlorophyll content only in shade. Principal component analysis classified the 38 genotypes into three groups. These groups were classified as tolerant, moderately tolerant and susceptible to drought stress based on combined traits scores. Some of the best-performing genotypes identified under natural drought stress were: A1I197 x SCA9, AMAZ15/15xPA13, Pound7, xPA7/808, and All 197 x T60I887, which can be used as planting materials in denuded areas.