Potential coconut (Cocos nucifera L.) genotypes for farmers: Evaluation of agronomic traits in a lethal yellowing disease endemic zone in Ghana

Abstract

A four-year study was conducted to evaluate selected vegetative and reproductive characteristics in four coconut genotypes namely: Niu Leka Dwarf (NLD), New Guinea Brown Dwarf (NGBD), Malayan Green Dwarf (MGD), Indonesian Brown Dwarf (IBD), and a hybrid between Sri Lankan Green Dwarf and Vanuatu Tall (SGDVTT), which was used as a control. The study was located at Anwea in the Western Region of Ghana, an endemic zone to the lethal yellowing disease. This experiment was laid out in a randomized complete block design (RCBD) in three replications. Results showed a significant higher growth for NGBD, IBD, and NLD in stem girth, leaf length, petiole length, and number of leaflets. NGBD, IBD, and SGDVTT also recorded significantly higher reproductive characteristics. Time taken for first flowering was noticed in IBD (41.30 months). NGBD recorded the highest number of female flowers (27.80), number of spikelets with female flowers (17.20), and total number of spadix (12.50) seasonally. Significant and positive correlations were observed between the number of leaves emitted, and the number of female flowers produced in the coconut genotypes except for MGD. The highest correlation between these vegetative and reproductive characteristics was expressed in IBD while the least was observed in the MGD genotype. MGD also recorded the least number of spikelets with female flowers, suggesting that this genotype is not likely to produce high number of fruits and should not be included in future breeding programs. Low and less robust characteristics were expressed in both SGDVTT, and MGD in the growing period, which could be ascribed to the rather low number of leaflets observed in these genotypes. Conclusions from this study suggest that NGBD, IBD, and NLD are potential genotypes to be integrated into further breeding programs across coconut-growing regions in Ghana.