INFLUENCE OF SOWING DATES AND MINERAL FERTILIZER RATES ON TILLERING DYNAMICS AND PRODUCTIVE TILLER NUMBER IN SPRING SOFT WHEAT (TRITICUM AESTIVUM L.)

Abstract

Productive tiller count per plant is a primary yield-determining component in spring soft wheat (Triticum aestivum L.). A three-year field experiment (2023–2025) was conducted to evaluate the interactive effects of two sowing dates (the third decade of March vs. the first decade of April) and six mineral fertilizer application rates (ranging from N_0 P_90 K_60 to N_210 P_90 K_60) on the productive tillering performance of two spring wheat cultivars ('Janub Gavhari' and 'Parvoz'). The results revealed that sowing in the third decade of March combined with nitrogen application at N_180 P_90 K_60 " kg/ha"  generated the highest number of productive tillers per plant (1.46 tillers/plant in 'Janub Gavhari' and 1.48 tillers/plant in 'Parvoz'). Delaying sowing to early April led to a significant decline in productive tillering across all fertilizer regimes. Furthermore, increasing nitrogen application beyond 180" kg N/ha"  to 210" kg N/ha"  induced a clear vegetative depression, reducing productive tiller counts. Overall, cultivar 'Parvoz' demonstrated superior tillering capacity and response to mineral nutrition compared to 'Janub Gavhari'.