Climate change poses significant threats to agriculture, including food security, livelihoods and economic growth. Based on the importance of cocoa, there is a need for sustainable crop production and resilience to anticipated changes in rainfall and temperature in the future. Irrigation is an important climate-smart practice for alleviating abiotic stress and enhancing crop productivity, and irrigation is seldom practiced in the cacao orchards of West Africa. Studies were conducted to examine the effects of dry season gravity drip irrigation on the rootzone moisture, tree water use (evapotranspiration), leaf area index and yield of cacao in a rainforest zone of Nigeria. Irrigation treatments were based on water application at 5- and 10-day intervals and 50, 70 and 100% Pan evaporation, which was applied using point source emitters on drip lines. The soil moisture content, photosynthetic active radiation, leaf area index and extinction coefficient differed among the irrigation treatments. Deficit irrigation (10-day and 50% EPan) enhanced water use efficiency by 25–44% (30 and 50% water savings), while full irrigation enhanced soil moisture, cacao ET, and pod and bean yields. This study established irrigation and water requirements for cacao in the dry season and confirmed the relevance of irrigation for enhanced cacao performance and climate mitigation.
Cocoa is a leading export crop to the world market and Cote D’Ivoire, Ghana, Nigeria and Cameroon in Africa, accounts for about 70% of the global supply. However, increasing global warming with attendant high ambient temperature had affected yields in the tropical regions of Africa. The data of 61 years (1961 – 2021), area harvested (ha), yield (kg/ha) and temperature (OC) were sourced from the database of Food and Agricultural Organisation Corporate Statistical (FAOSTAT). Least squares regression and correlation analysis models were used for data analysis. Results showed that mean ambient temperature in Cote D’Ivoire, Ghana, Nigeria and Cameroon have increased by 0.7661, 0.7507, 0.7333 and 0.6400 OC for a total of 51, 51, 50 and 49 years respectively, while mean decreases were 0.1541, 0.1693, 0.1710, 0.1392oC for 10, 10, 11 and 12 years respectively. Annual average temperature increase was highest (0.0243oC) in Cote D’Ivoire with regression coefficient (R2) of 0.7232 and least (0.0200oC) in Nigeria at R2 of 0.6380. However, in both countries, annual temperature decreased by 0.0012o and 0.0007o with R2 of 0.0052 and 0.0014 respectively. The mean annual temperature increase in Ghana and Cameroon were 0.023o and 0.0204o with R2 of 0.7364 and 0.6965 respectively, while the decreases were 0.0019o and -0.0011o with R2 of 0.0152 and 0.0431 respectively. The cocoa cumulative yield (kg/ha) reduced by 105.8, 90.8 and 75.0kg/ha respectively in Cote D’Ivoire, Ghana and Cameroon when temperature decreased, but increased by 12.5kg/ha in Nigeria during same temperature decreasing trend. In Ghana and Cameroon, cocoa annual yield was higher in the years of temperature increase, while decreased ambient temperature enhanced cocoa yield in Nigeria and Cote D’Ivoire. Hence, to enhance cocoa yield in the top four cocoa producing countries of Africa, the ambient temperatures should be controlled through the adoption of Good Agricultural Practices (GAP).
Weed incidence and biomass in tree crop plantations are mainly influenced by environmental, farm management practices and cropping systems. Manipulation of intercropping systems to improve weed management in coffee intercropped with oil palm requires a better understanding of spatial and temporal dynamics of weeds. To evaluate the effect of weed incidence and biomass in coffee intercropped with oil palm in avenue and hollow square arrangement, a study was carried out in Cocoa Research Institute of Nigeria (CRIN) in two locations. The locations are Idi-Ayunre (7°25'N, 3°24'E) (an alfisol) and Uhonmora (6°5'N, 5°50'E) (ultisol) in rainforest and derived savannah parts of Nigeria respectively. The experiment had three treatments comprising coffee sole (control), coffee with oil palm (Hollow square) arrangement and coffee with oil palm (Avenue) planting. Coffee was planted 3.0 m apart while oil palm was planted 9 m apart. Equal size of land area was used for coffee in each treatment. The experimental design was Randomized Complete Block (RCBD) with three replicates. Data on vegetative growth of coffee, weed incidence and biomass were taken at three-monthly intervals. The result showed that coffee/oil palm (Hollow Square) had the least weed incidence and biomass closely followed by coffee/oil palm (Avenue) planting. The control had the highest weed biomass which was significantly different from Hollow square and Avenue planting at P ≤ 0.05. The morphological parameters on coffee followed the same pattern but Hollow square arrangement was significantly higher than Avenue and control at P ≤ 0.05.
A nursery experiment was carried out in Akure (rain forest zone), south-western Nigeria to study relative effect(s) of some organic wastes as fertilizers on growth performance, soil and leaf chemical composition of cocoa seedlings (Theobroma cacao L.) in the nursery. The experiment comprised of five treatments: Cowpea Pod Husk (CPH) (2.5 t/ha), cocoa pod husk ash (CPHA) (2.5 t/ha), kola pod husk (KPH) (2.5 t/ha), NPK15-15-15 (2.5 t/ha) and control (no fertilizer application). Each treatment was applied to 2.5 kg of soil filled polythene bags containing cocoa seedlings. The experiment was arranged in completely randomized design (CRD) with three replications. The organic wastes increased significantly (P>0.05) the plant height, stem diameter, leaf area, number of leaves, fresh root and shoot weights and dry root and shoot weights of cocoa seedlings. The treatments also increased significantly (P>0.05) soil and leaf N, P, K, Ca, Mg, Na, soil pH and organic matter (OM) content relative to the control. Kola pod husk (KPH) was the most effective in improving cocoa growth, leaf and soil chemical composition. Key words: Cocoa, growth, organic matter, NPK, cowpea pod husk, cocoa pod husk ash, kola pod husk.
Three field experiments were conducted to examine the separate and combined effects of wood ash and goat dung manure on leaf nutrients composition, growth and yield of Amaranthus cruentus at Akure, Southwest Nigeria. The treatments compared were: no treatment, 2t/ha goat dung, 2t/ha ash + 2t/ha dung, 2t/ha ash + 4t/ha dung, 2t/ha ash + 6t/ha dung, and 2t/ha ash + 8t/ha dung. Application of 2t/ha ash, 8t/ha goat dung, and combined application of ash and different quantities of goat dung to soil increased leaf N, P, K, Ca and Mg contents significantly compared with no treatment. Separate application of 8t/ha dung, and combined application of 2t/ha ash with each of 2, 4, 6 and 8t/ha dung increased number and yield of leaves, leaf area and number of branches significantly compared with no treatment. Ash and goat dung complement each other as to their effects on nutrients contents, growth and yield of amaranthus. Addition of 2t/ha ash to 8t/ha dung increased stem weight and leaf yield by 68 and 54% respectively. Combined application of 2t/ha ash and 8t/ha dung gave 513 and 342% increase in stem weight and leaf yield respectively compared with no treatment.
[Niger Agric. J. 33 (2002): 46-49]
An intercropping experiment involving coffee (sole), coffee/rice, coffee/plantain and coffee/ rice/plantain was carried out between 2007 and 2008 at the Cocoa Research Institute of Nigeria (CRIN) Uhonmora Substation, Edo State situated in a derived Guinea Savanna agro-ecological zone of Nigeria. The experiment was a Randomized Complete Block Design (RCBD) with above mentioned treatment and replicated three times. The spacing used for coffee and plantain was 3 m apart respectively while rice was sown 30 cm apart. Morphological parameters such as plant height, stem girth, leaf area and canopy score were taken on coffee monthly while the survival count were taken after two months of field establishment. Yields of the component crops were also collected at maturity. Data collected were subjected to statistical analysis of variance and LSD used to separate the means that were significant. Result obtained showed 98% survival without any significant difference among the treatments. On vegetative growth, coffee/rice and coffee/plantain were significantly higher (p < 0.05) than coffee sole and coffee/rice/plantain in plant girth and leaf area but not significantly higher in all the months. Plant height however did not follow the same trend as height in coffee sole was slightly higher than coffee/rice. However, the difference was not significant. But coffee/plantain was still significantly higher (P < 0.05) than coffee/rice/plantain. The least was recorded in coffee/rice/plantain intercrop. Grain and bunch yields from rice and plantain respectively in the intercrops compare favourable well to what obtain from coffee sole. From the result obtained, it could be concluded that there was no deleterious effect on growth when rice and plantain were intercropped with coffee. Therefore coffee/rice and coffee/plantain intercropped with better performance could be recommended to coffee farmers in Nigeria rather than sole planting of coffee.
An investigation was carried out in Cocoa Research Institute of Nigeria (CRIN), Uhonmora Station, Edo State to evaluate the effect of transplanting positions of cacao (Theobroma cacao L) seedlings with plantains under field condition. Four treatments were evaluated: Plantain suckers on top of cacao seedlings at transplanting (PTCT), Cacao seedlings on top of plantain suckers at transplanting (CTPT), Cacao seedlings transplanted 30 cm apart from plantain suckers (CT30P) and Cacao seedlings transplanted 150 cm apart from plantain suckers (CT150P) as control. The experiment was arranged in Randomized Complete Block Design (RCBD) with three replications. Plantain suckers were planted at 3 x 3m spacing as shade crop while cacao seedlings (hybrid) were planted on treatment basis. The experiment was monitored for 22 months after transplanting. Data were collected on plant height, number of leaves, stem diameter, number of branches and leaf area at 3, 4, 5, 12, 13, 14 and 15 Months After Transplanting (MAT), and on Survival count (%) at 10 and 22 MAT. The data were analyzed with analysis of variance (ANOVA) as well as descriptive statistics, and significant means separated by Duncan multiple range test (P<0.05). The result showed that cacao seedlings on top of plantain (CTPT) at transplanting had the highest percentage of 91.67 and 75.00 survival count at 10 and 22 MAT, respectively, closely followed by plantain on top of cacao seedlings at transplanting (89.00 % and 72.00%). When compared with CT150P, CTPT increased the plant height, number of leaves, stem diameter, number of branches and leaf area at 4 MAT, at 15 MAT, at 3, 13, 14, 15 MAT, at 3, 15 MAT and at 13, 14,15 MAT, respectively by 1%, 10%, 61%, 2%, 3%, 8%,46%, 11%, 5%, 3% and 13%, respectively. Therefore, cacao seedlings transplanted on top of plantain was the most effective treatment for improving cacao seedling establishment and growth under field condition.
