Soil Chemical Properties and Yield of Tomato as Influenced by Different Levels of Irrigation Water and Fertilizer

This research was conducted under greenhouse conditions to evaluate the optimum combination of irrigation and fertilizer levels to attain the best yield and quality of tomato crop. The experiment was conducted by using a split-plot design with three replicates. Irrigation levels were applied to the main plots and fertilizer levels to the sub-plots. For each experimental unit, the irrigation levels were W۱=۸mm/day, W۲=۷mm/day, W۳=۶mm/day , and W۴=۵mm/day. Fertilizers treatments varied during the growing season. For the period after transplanting till flowering, the treatments consisted of weekly applications of F۱= (N۱, P۱, K۱, respectively, ۹.۸, ۶.۱۳, ۷.۳۵ g /plot), F۲= (N۲, P۱, K۱, respectively,۱۴.۷, ۶.۱۳ , ۷.۳۵g/plot), F۳= (N۲, P۲, K۱, respectively,۱۴.۷, ۹.۱۹, ۷.۳۵ g/plot), and F۴=(N۲, P۲, K۲, respectively, ۱۴.۷, ۹.۱۹, ۱۱.۰ g/plot). Fertilizer levels were increased as the plants developed during the growing season. Plant height and the number of flowers per tomato plant were measured during the growing season and at harvesting time. Random samples of tomato leaves and fruits were taken from each experimental plot to determine the percentage of dry matter, total nitrogen, phosphorus, and potassium contents of fruits and leaves. Total yield during harvesting period and average fruit weight were also measured. Results indicated that irrigation and fertilizer levels had significant effects on the number of flowers per plant and W۱F۲ combination was significantly the most effective treatment compared to the other treatments. Plant height was not affected significantly by any treatment. The total yield significantly increased in W۳F۱ treatment. Average fruit weight was significantly higher in W۲F۳ as compared to the other treatments .The percentage of dry matter was significantly affected by the treatment W۳F۳ in both leaves and fruits. Total leaf contests of nitrogen, phosphorus, and potassium significantly increased in W۲F۴ treatment. Total nitrogen content in tomato fruits did not show any significant difference among different treatments, whereas fruit phosphorus and potassium contents significantly increased in W۲F۳ and W۴F۴ treatments.

Keywords:

Tomato , Fertilization , Greenhouse , Irrigation levels