DEVELOPMENT OF GREENHOUSE AND CONSTRUCTION OF DRIP HYDROPONIC PLANTING STRUCTURE TO TEST THE PERFORMANCE OF THREE VEGETABLES

Abstract

The purpose of growing crops under greenhouse and soilless farming conditions is to extend cropping season and to protect from adverse environmental conditions such as extreme temperatures and precipitation and from diseases and pests. Greenhouse and soilless farming production methods normally require high level of technology to obtain adequate economic returns on investment. Quality and/or quantity are high priority for greenhouse and soilless crop production. Greenhouse and drip hydroponic soilless farming structure was developed and constructed for field experiment conducted between March and August, 2017 in Agricultural and Environmental Engineering experimental farm at Oba-nla, Federal University of Technology, Akure, Nigeria. The principle involved economic use of water and nutrients. The aim of this research is to comparatively assess the effect of organic substrates (sawdust and rice husks) using drip hydroponic soilless farming method, on the performance of Tomatoes (UC82B variety), African Spinach and cayenne pepper. Results were compared with the open cultivation system as a control. The experiment was carried out in a completely randomized design with three treatments. Agronomic and physiological responses of these vegetables were observed using different support and planting systems. The vegetative growth, yield, biomass weight, determination of quantity of water and nutrient, proximate and mineral composition were measured. Other parameters assessed to achieve the objectives of this study included physicochemical properties of the substrates. The results showed that rice husk as supporting system for these vegetables gave the highest plant height (42.74 cm, 29.32 cm and 21.97 cm), number of leaves (120.60, 47.51 and 39.60) and stem girth (0.57 cm, 0.38 cm and 0.34 cm) respectively while soil (conventional farming) as supporting system for these vegetables gave the lowest plant height (27.80 cm, 20.43 cm and 17.84 cm), number of leaves (67.40, 41.93 and 29.36) and stem girth (0.42 cm, 0.29 cm and 0.30 cm) respectively. Higher yields were also recorded from rice husk for the three vegetables while the soil (conventional farming) had the least yield. The rice husk as substrates for these vegetables recorded significantly higher fruit weight substrate-1 (410.6 kg, 89.6 kg, 31.89 kg) respectively and fresh weight of root substrates-1 (39.84 kg, 47.45 kg, 24.95 kg) respectively while soil (conventional farming) had the least fruit weight substrate-1 (368.2 kg, 79.8 kg, 29.50 kg) respectively and fresh weight of root substrates-1 (37.23 kg, 42.24 kg, 19.55 kg) respectively. The physiological appearance and the yields were significantly (P<0.05) affected by the various treatments with its physicochemical features. The proximate and mineral composition of the fruits and the vegetables were within the recommended range by World Health Organization (WHO) but were Significantly (P<0.05) affected by the treatments effects as a result of its physicochemical features. With the outcome of this research, it is strongly advised that soilless farming should be embraced by farmers especially in areas where there is limitations of land for agricultural activities. This study further recommends governmental supports to enhance soilless farming in Nigeria