Studies on the Yield and Nut Quality of Four Coconut(Cocos Nucifera L) Varieties at the Nigerian Institute for Oil Palm Research(NIFOR), Benin City.

Abstract

Studies were carried out on the yield and nut quality of four coconut (Cocos nucifera L.) varieties which include the West African Tall (WAT), Malayan Green Dwarf (MGD), Malayan Orange Dwarf (MOD) and Malayan Yellow Dwarf (MYD) at the Nigerian Institute for Oil Palm Research, NIFOR, Thirty (30) palms were selected at random from each population for nut yield, inflorescence and flower morphology data collection. Ten (10) palms and ten (10) nuts per palm were selected randomly from the already selected palms for each accession for fruit components yield data collection. Data were subjected to analysis of variance (ANOVA) of a completely randomized design (CRD) using a computer. Where significant F-tests were obtained treatment means were separated by using Duncan's New Multiple Range Test (DNMRT). Male flowers and pollen yield of an inflorescence and the fruit components yield data were subjected to regression and correlation analysis. The results showed that the ratio of female flowers to spikelets did not influence the number of nuts produced per palm per year in the varieties. There were no significant differences (P>0.05) in the per cent pollen germination (PPG) of pollen stored in the desiccator using calcium chloride as desiccant and the deep freezer. The duration of storage of pollen has a significant effect on pollen viability (P< 0.05). Pollen yield was positively and significantly correlated with the weight of male flowers and the ideal duration of oven drying for optimum viable pollen yield was 24-36 hours. The nut yield per palm per year of the WAT variety was significantly different from the nut yield per palm per year of the MGD population (P< 0.05). The WAT yielded 52.8+ 2.2 nuts per palm per year (1674.9 kg, copra, 963.5 kg oil and 758.5 kg cake/hectare/year). This was fallowed by the MOD which produced 48.8+ 2.8 nuts/palm/year (1363.3 kg copra, 799.5 kg oil and 696.0kg cake/hectare/year), MYD which yielded 47.9 + 2.3 nuts/palm/year (1M9.0 kg copra, 615.0 kg oil and 594.5 kg cake/hectare/year) and MGD which produed 44-2+ 2.5 nuts/palm/year (1141.6 kg copra, 533.0 kg oil and 594.5 kg/hectare/year). The mean weight of a single fruit, dehusked nut, busk, split nut, shell and copra per nut of the WAT population were significantly different from the mean weight of these variables in the dwarf accessions at 5% level of probability. The mean of the split nut weight of MOD was significantly different from the meann split nut weight of MGD and MYD while the average copra yield per nut of MOD was significantly different from the mean copra yield/nut in MYD as determined by the Duncan's New Multiple Range Test (DNMRT) at 5% level of probability. There were positive and significant correlations between the weight of hit and nut in MGD and MOD, split nut and copra in WAT and MGD, nut and split nut in MGD, nut and water in MGD and MYD, split nut and copra in WAT and MGD, fresh meat and split nut in WAT, MGD and MOD aT 5% level of probability. The annual yeild per hectare was generally low and it is believed to be connected with the non application of potassium and Nitrogen fertilizers for many years, meiotic irregularities in MGD and MYD, three months of drought each year, susceptibility of palms to Lethal Yellowing Disease (LYD) and poo field management.