Effect of NPK levels on soil properties after the harvest of water spinach under central Telangana agro-climatic conditions

The present investigation entitled "Effect of NPK Levels on Soil Properties after the harvest of Water Spinach under Central Telangana Agro-climatic Conditions" was undertaken during 2024-2025 at the Post Graduate Institute, SKLTGHU, Mulugu, Siddipet District, Telangana. The study aimed to identify superior varieties and assess their interaction effects on soil physico chemical properties and nutrient availability after the harvest of water spinach. The experiment was laid out in a Factorial Randomized Block Design (FRBD) with two factors, factor-I: varieties (Kashi Manu and CHWS-01) and factor- II: six NPK levels (F₁: 40:40:40, F₂: 60:40:40, F₃: 80:40:40, F₄: 60:60:60, F₅: 60:40:60, F₆: 80:40:60 kg/ha), comprising 12 treatment combinations replicated thrice. The results demonstrated notable variations between varieties and fertilizer levels. Kashi Manu (V₁) recorded higher values for soil pH (7.15), electrical conductivity (0.46 dS/m), available nitrogen (135.02 kg/ha), and available phosphorus (24.59 kg/ha). Conversely, CHWS-01 (V₂) excelled in available potassium (183.88 kg/ha). Among the fertilizer treatments, 60:60:60 NPK kg/ha (F₄) and 80:40:60 NPK kg/ha (F₆) resulted in the highest soil pH (7.16), 80:40:60 NPK kg/ha (F₆) records highest EC (0.66 dS/m), 40:40:40 NPK kg/ha (F₁) recorded highest available nitrogen (161.71 kg/ha), available potassium (197.2 kg/ha) and 60:40:40 NPK kg/ha (F₂) recorded maximum available phosphorus (26.47 kg/ha). Interaction effects revealed that (V₁F₄) and (V₁F₆) achieved the highest soil pH (7.18), (V₁F₆) showed maximum EC (0.67 dS/m). (V₁F₃) produced the highest available nitrogen (180.43 kg/ha) while V₁F₂ recorded the highest available phosphorus (32.32 kg/ha). The maximum available potassium (225.32 kg/ha) was obtained with (V₂F₁). Overall, the study demonstrated that varietal and NPK combinations significantly influence soil nutrient dynamics in water spinach, with CHWS-01 (V₂) coupled with appropriate NPK doses showing promising potential for nutrient use efficiency under central Telangana conditions.