DESIGN AND CONSTRUCTION OF A GREENHOUSE FOR EVALUATION OF THE PERFORMANCE OF OKRA IN THE SAHEL REGION OF ONDO STATE, NIGERIA

A 4.5 x 6.74 m greenhouse was designed and constructed at Rufus Giwa Polytechnic, Owo, Nigeria to evaluate the performance of okra under the greenhouse condition. The greenhouse consists of the frame, woven net and solarig cover of 170 gsm. Drib/bucket irrigation system with irrigation frequency of 2 times daily was used for the research. An experiment was conducted in the greenhouse during the dry season to determine the effects of greenhouse and liquid organic fertilizer on the performance of okra. In the experiment, a fertigation process was performed with varying quantities of the Super Gro liquid organic fertilizer, 0, 20, 40 ml which were proportionally mixed with the irrigation water for each treatment. Daily measurement of the soil temperature was recorded and the morphological features were measured every week at the mid-flowering stage of the plant during the experiment. The results of the research reveal that the plant height was initially the same and later became higher in the greenhouse than the one in the control plot. The same observation was made on the leaf surface area of okra, but higher values were later observed in the control plot. The maximum leaf area recorded in the greenhouse was 0.76 x 103 m2 while the one in the control plot was 1.313 x 103 m2. There was no significant difference in the number of leaves in both the greenhouse and the control experiments in the first 2 weeks of the experiment but later became higher in the control plot. Higher percentage of 83.33% germination was recorded in the greenhouse against 58.33 % of the control plot. Negative effect of the inorganic fertilizer on the yield of okra was observed as the yield decreased with increase in the quantity of fertilizer applied both in the greenhouse and the control plot. The results therefore show that greenhouse has the potential to improve the growth performance of okra. They also reveal that the inorganic fertilizer has no influence on the fruit yield of okra. It is recommended that this research should be repeated during the raining season for seasonal evaluation of the performance of okra in the greenhouse.