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Optimum water need of sweet pepper and the critical irrigation level to be applied in order to achieve a reasonable economic yield was determined. Greenhouse (controlled) was conducted with sweet pepper subjected to three (3) varying water applications; 100% full irrigation treatment (FIT), 70% FIT and 50% FIT. Crop water use (evapotranspiration) was determined using the water balance method. For the agronomic parameters measurement, weekly measurements of plant height, stem diameter, number of leaves and canopy temperature were measured. The sweet pepper were determined in batches during harvest. Result showed that the growth parameters significantly (p < 0.05) increased with increase in water application. The highest value of 707.78 g was recorded at irrigation treatment that received 70% of FIT while the least value was recorded in treatment that received the least amount with a value of 665.2 at 50% FIT. Overall, similar yield (p > 0.05) was observed in the yield quantification. This showed that about 50% of irrigation can be saved to irrigate additional plant. Highest values of irrigation for the irrigation and crop water efficiencies were obtained at the deficit irrigation. [ABSTRACT FROM AUTHOR]

Studies on radiation use and physiological development such as leaf area of crops planted under screen-house and ambient environments is very scarce in the sub-Saharan part of Africa. This research therefore was aimed at investigating the radiation use of tomato under screen-house and ambient environment to determine its leaf area index (LAI) under different irrigation water treatments: 100% Field capacity (100%FC), 75% FC, 50% FC and rain-fed condition in ambient environment. AccuPAR LAI 80 Ceptometer (Decagon Device) was used for direct measurement of the above and below canopy photosynthetic active radiation, fraction of beam interception (Fb), leaf distribution coefficient (chi), leaf area index (LAI), zenith angle (ϑ), and ratio of below canopy PAR and above canopy PAR (τ). The radiation uses efficiency of tomato planted in screen-house and under ambient condition was evaluated from the yield of tomato and fraction of beam intercepted by tomato plant. Result showed RUE values of 0.29 ± 0.02 kg MJ-1m-2, 0.56 ± 0.002 kg MJ-1m-2, 0.6 ± 0.001 kg MJ-1m-2 and 0.21 ± 0.01 kg MJ-1m-2 for the tomato plant grown under 50%, 70%, 100% irrigation level, and control sample, respectively. The highest LAI values (0.42) was obtained from tomato under 75% irrigation water level at the ninth weeks after transplanting (9 WAT), which was found to be 22% higher than the tomato under the 100% FC irrigation water level (0.27). The research information has revealed the yield potential and effectiveness of radiation utilization of tomato irrigated to 100% FC in controlled environment when compared with tomato grown under ambient condition. [ABSTRACT FROM AUTHOR]

Proper utilization of land is essential to soil quality maintenance and sustainable agricultural development. This study was conducted to evaluate effects of land use management on physico-chemical characteristics of soils in Ekiti State, Southwestern Nigeria. In this study, a total of 105 sampling points in 35 locations comprising of the 3 land uses were sampled. Random sampling pattern of 3 sampling points per location were carried out and undisturbed soil samples were collected at depths up to 30 cm. Soil physical properties (bulk density (BD), water holding capacity (WHC), and particle size distribution) and chemical properties (organic matter content (SOM), cation exchange capacity (CEC), phosphorus (P) and organic nitrogen (SON)), were determined and evaluated. Results showed that natural forest on the overall accumulated more nutrients than plantations and cropland. The highest SOM value of 4.07 % was recorded in the natural forests, while the lowest value of 1.52 % was found in the croplands. Organic matter accumulation showed a decreasing trend in the order: forest > plantation > cropland. Natural forest soils had significantly higher volumetric moisture content (VMC) than plantations and croplands. Correlation analysis of the 11 physico-chemical properties for the study area, showed a significant correlation among 70 of the 190 soil attribute pairs. Land use system reveals a significant decline of soil quality under cropland. Management systems by which soil could be improved towards the development of suitable agricultural management systems must be incorporated during land cultivation. In order to have sustainable land use systems, land use development must not be only economically sustainable but also socially acceptable and environmentally sound. Therefore, strategies to improve agricultural productivity have to seek a sustainable solution that better addresses soil fertility management. [ABSTRACT FROM AUTHOR]

Cation exchange capacity (CEC) is a good indicator of soil productivity and is useful for making recommendations of phosphorus, potassium, and magnesium for soils of different textures. Soil water holding capacity (SWHC) defines the ability of a soil to hold water at a particular time of the season. This research predicted CEC and SWHC of soils using pedotransfer models developed (using Minitab 17 statistical software) from basic soil properties (Sand(S), Clay(C), soil pH, soil organic carbon (SOC)) and verify the model by comparing the relationship between measured and estimated (obtained by PTFs) CEC and SWHC in the Forest Vegetative Zone of Nigeria. For this study, a total of 105 sampling points in 35 different locations were sampled in the study areas. Three sampling points were randomly selected per location and three undisturbed samples were collected at each sampling point. The results showed success in predicting CEC and SWHC from basic soil properties. In this study, five linear regression models for predicting soil CEC and seven linear regression models for predicting SWHC from some soil physical and chemical properties were suggested. Model 5 [CEC = -13.93+2.645 pH +0.0446 C (%)+2.267 SOC (%)] was best for predicting CEC while model 12 [SWHC (%)=36.0- 0.215 S (%)+0.113 C (%)+10.36 SOC (%)] is the most acceptable model for predicting SWHC. [ABSTRACT FROM AUTHOR]