Effect of potassium spraying and spraying dates on some growth, yield and chemical traits of tomato cv. Polonia

This study was performed during the 2022 cropping season in the experimental fields of the Horticulture Department, College of Agriculture, University of Anbar, to examine the effects of foliar potassium (K) concentrations and application schedules on tomato growth, yield and quality of fruit. Tomato saplings (Polonia cv.) were transplanted to the open area and the experiment was structured in a randomized complete block design (RCBD) with three replications. Two factors were explored: five K doses (0, 1000, 2000, 3000 and 4000 mg L-¹) and three application timelines (10, 21 and 42 days post-transplanting). The research assumes that foliar application of potassium at advanced concentrations and proper spraying times can effectively improve vegetative growth, yield factors and chemical traits of tomato plants. This hypothesis handles a critical comprehension gap in insight the association between potassium supply and plant physiological reactions under the agro-ecological environments of Iraq. Furthermore, confirming or refusing this hypothesis has practical significance for green agriculture, as it supplies executable guidance for enhancing both yield and economic returns in tomato yield. The results revealed that the treatment K2 (2000 mg L-¹) significantly improved height of plant and leaf area, while K4 (4000 mg L-¹) enhanced dry weight, flowers number, yield of fruit and leaf potassium content. Spraying at S3 (42 days after replanting) significantly raised most traits of growth and yield. The interaction of potassium treatment and applying schedule disclosed that K4S3 and K2S3 treatments achieved the highest values for the studied traits. These findings highlight the originality and significance of the research, illustrating that a carefully enhanced potassium application strategy, combined with proper applying schedules, can immediately enhance tomato productivity and quality of fruit. generally, this study provides both scientific perceptions into nutrient–plant relations and practical guidance for enhancing farmers’ yields and gainfulness in fresh market and managing tomato production systems.