ABSTRACT

The research presents a greenhouse with hydroponic system developed and tested with Roma VF tomato variety. The microclimatic condition which determined the activities of the plant inside and outside the greenhouse system were at average operating temperatures of 29.53^oC and 26.53^oC, relative humidity of 71.76% and 75.65%, average solar radiation of 314.59w/m²and 426.88w/m², with wind speed values of 0.08m/s and 1.69m/s for inside and outside the greenhouse system respectively. The disparity which existed between the greenhouse and environmental condition reflected on plant performance. Hargreaves second temperature method was used in evaluating the evapotranspiration between the greenhouse and the environment. The result showed a lower evapotranspiration rate inside the greenhouse which favored plant activities. Comparative analysis of selected plant parameters under the greenhouse and ambient condition showed an average length of leaves inside the greenhouse as 72.5mm against 67.6mm ambient value, with a difference of 4.9mm in length.  Similarly, the average widths of leave and tomato yield were 22.6mm and 3.5kg inside the greenhouse, with 20.1mm and 2.9kg outside the greenhouse. The research concludes that the condition inside the greenhouse is better for the tomato production. Statistical analysis using factorial design at 5% probability level was carried out to assess the effect of the various factors on plant parameters at 25, 50 and 75 days planting. The analysis presents drip irrigation with a higher significant effect in comparison to sprinkler system when assessed with all the plant parameters such as length of leaves, width of leaves, number of leaves, plant height, stem diameter and yield. Two quantities (6grams) of fertilizer also showed higher significant effect than 1 quantity (2grams) of fertilizer. The cocopeat+perlite (3:1) soilless media showed the highest effect followed by cocopeat and perlite with the least effect when analyzed with all plant parameters. The improved physical properties of the cocopeat+perlite (3:1) reflected on the plant performance when compared to cocopeat and perlite soilless media only. Models for predicting each plant parameters was developed with all R² values higher than 0.87 with standard deviation as low as 0.15. The numerical optimization goals using design expert software were to keep all factors in range and maximize all plant parameters. The software identified a combination of drip, 2quantity (6gram) of fertilizer and cocopeat+perlite (3:1) as optimal combination with respective values of each plant parameters presented.