EVALUATION OF TOMATO YIELD WITH DIFFERENT LEVELS OF N AND K FERTIGATION

摘要

The unlimitted use of water and fertilizer cause an imbalance in the crop nutrients and creates environmental pollution problems. The combination of water and fertilizer rates in the fertigation system, not only, has decreased the envirnmental pollution problems, but also, makes the optimum use of fertilizers. Therefore, the fertilizer use alongwith spread out application on the sensitive and needed occassions will be easy. In this study, a factorial experiment was carried out in a randomized complete block design (RCBD), in three replications in Torough station, which was located in Agricultural Research and Natural Resources (ARNR) Center of Khorasan, Mashhad. The experimental factors were Nitrogen (N) and Potassium (K) fertilizers with three different levels, which included; fertilizer recommendations based on the soil test results (N1, K1), 20% less than the recommendations (N2, K2), and 40% less than the recommendations (N3, K3). On the basis of analysis of two year data by the Statistical Analysis System Package (SAS) method, and the mean yield comparison of different treatments by Tucky’s method (J = 0.05), the maximum fruit yields were obtained from N3K2 and N2K3 treatments which were of the order of (82.13, and 82.01) ton/ha.The relative Water Use Efficiency (WUE) were (9.45, and 9.44) Kg/m3 respectively. The results showed that, the required N and K fertilizers in the fertigation method were respectively (40% and 20%) less than the surface irrigation. The fertigation method, in addition, decreases the fertilizer use, will also increase the yield and the WUE.