Soil properties and yield of pepper (CapsicumchinenseJacq.) as influenced by Almond leaf-basedcompost and tillage in Ibadan, Nigeria

Abstract

Soil properties and yield of pepper are affected by soil fertility and cultural practices such as tillage. Although, composts improve soil structure and enhance soil fertility and crop yield, limited information is available on the combined effect of tillage and compost on the yield of pepper. Therefore, a study was conducted in 2010 and 2011 to evaluate the effect of almond leaf-based composts on soil properties and yield of C. chinense under the two commonly practiced tillage systems in Ibadan. The influence of thirteen experimental treatments comprising of almond leaf-based composts [Almond leaves + Poultry manure (AP) at 9.7, 12.1, and 14.5 t/ha; Almond leaves + Cattle manure (AC) at 14.3, 17.9, and 21.5 t/ha; and Almond leaves + Swine manure (AS) at 13.0, 16.3, and 19.6 t/ha]; NPK 15-15-15 at 0.2, 0.25, and 0.3 t/ha; and a control (without fertilizer) on the growth and yield of C. Chinense were investigated in a Screen house. Each treatment was mixed with 5 kg soil and arranged in a completely randomized design with four replications. The performances of the best rates in each treatment: AP (14.5 t/ha), AC (14.3 t/ha), AS (13.0 t/ha), NPK (0.25 t/ha) and control from Screen house studies, under two tillage methods: Manual Clearing (MC) and Manual Ridging (MR) were investigated in the field. The ten treatment combinations (MC; AP/MC; AC/MC; AS/MC; NPK/MC; MR; AP/MR; AC/MR; AS/MR and NPK/MR) were laid as randomised complete block design with four replications. Data were collected on plant height (PH), number of leaves (NL), and number of branches (NB), stem girth (SG), root length (RL) and fruit yield (FY) of pepper. Soil samples were collected and analysed for changes in nutrient content, soil porosity (SP), bulk density (BD), soil temperature (ST) and pH. Data were analysed using descriptive statistics and ANOVA at 0.05. In the Screen house, significant (p<0.05) differences were observed among the treatments for PH, NL, NB, SG and FY of pepper. The FY ranged from 44.5±1.7 (control) to 68.4±3.1 g/pot (AC, 14.3 t/ha). The highest FY of 68.4±3.1 g/pot of pepper recorded by AC (14.3 t/ha) was higher than those from NPK (0.25 t/ha) by 13.6%. In the field; PH, NL, NB, RL and SG of pepper were significantly (p<0.05) higher under MR than MC, respectively. The SP (54.4±1.6 and 46.4±1.8%), carbon (18.5±1.7 and 14.4±1.4 g/kg), nitrogen (4.3±0.4 and 3.3±0.4 g/kg), K (0.3±0.1 and 0.2±0.1cmol/kg),calcium (10.5±1.0 and 8.3±0.9 cmol/kg), CEC (15.9±1.3 and 13.4±1.2cmol/kg) and FY (6.6±0.6 and 3.6±0.3 t/ha) were significantly (p<0.05) higher under MR than MC, respectively. The BD and ST under MR were not significantly (p<0.05) different from MC. The FY under almond leafbased composts increased in the order: AS (5.0±0.7 t/ha) E‚ AP (5.3±0.7 t/ha) E‚ NPK (5.7±0.8 t/ha) E‚ AC (6.9±1.1 t/ha). Soil pH under compost-tillage (6.8±0.1) was higher than that of NPK-tillage (5.4±0.1) combinations. The SOC (25.5±2.7 g/kg), N (6.4±0.6 g/kg), K (0.5±0.2 cmol/kg), SP (59.5±0.9%) and FY (10.0±0.5 t/ha) under the combination of 14.3 t/ha AC/MR was significantly (p<0.05) higher than other treatments. Soil properties and yield of pepper were greatly improved under almond leaf-based compost and manual ridging. Thus, the combination of almond leavescattle manure compost at 14.3 t/ha and manual ridging is recommended for enhancing soil properties for pepper production in Ibadan.