Effect of Different Fertilizer Applications on Morphological and Physiological Traits of Spinach (Spinacia Oleracea L.) Grown Under Field Conditions

Abstract

This study investigated the effects of different fertilizer applications on the morphological and physiological characteristics of spinach grown under field conditions. The treatments included a control, chemical fertilizer (CF), three levels of farmyard manure (FYM) combined with CF, and three levels of biochar (BC) also combined with CF. The experiment was conducted in a randomized block design with eight treatments, two growing periods and two sowing periods (autumn: 15 October; spring: 15 March), and three replications, resulting in a total of 48 plots. Statistically significant differences were observed among treatments for several parameters, including plant number, leaf number, leaf area (cm(2) plant(-1)), SPAD value, leaf relative water content (LRWC, %), soluble solid content (SSC, degrees Brix), and membrane damage index (MDI, %). The CF + 30 t ha(-1) FYM treatment yielded the highest values for plant number (336.75 plants per 4 m(2)), leaf number (21.08 per plant), leaf area (48.09 cm(2) plant(-1)), SPAD value (60.86), LRWC (84.42%), and SSC (9.08 degrees Brix), whereas the control treatment showed the lowest values across all traits. The results demonstrate that increasing FYM rates significantly improved plant performance, and BC also showed potential as an effective organic amendment.