PHENOLOGICAL DEVELOPMENT AND GROWTH STAGE DURATION OF SPRING SOFT WHEAT (TRITICUM AESTIVUM L.) AS INFLUENCED BY SOWING DATES AND NITROGEN APPLICATION RATES

Abstract

A field experiment was conducted in 2025 to evaluate the effects of different sowing dates (late March vs. early April) and mineral fertilizer application rates (ranging from N_0 P_90 K_60 to N_210 P_90 K_60) on the phenological development and duration of vegetation phases in spring soft wheat (Triticum aestivum L.) cultivars 'Janub Gavhari' and 'Parvoz'. The findings demonstrated that optimal sowing in the third decade of March combined with nitrogen application at N_180 P_90 K_60 significantly extended the overall vegetation period by delaying reproductive transitions and maturity, thereby providing an extended window for dry matter accumulation. Over-fertilization (N_210 P_90 K_60) did not further prolong phenological phases, indicating a physiological saturation threshold at 180" kg N/ha" . Cultivar 'Parvoz' exhibited earlier phenological transition across all treatments compared to 'Janub Gavhari', confirming its genetic earliness.