IMPACT OF SPLIT NITROGEN APPLICATION ON PHENOLOGY AND TRAITS OF MAIZE (Zea mays L.)

Abstract

Maize quality seeds and grains is indispensable cultural input. Nitrogen splits provide nutrients at crucial apical bud (ear) prior to development. Keeping the above objectives two years consecutive research was carried out to elucidate maize performance under different N levels and N split application during crop year 2021 and 2022 respectively. A logical structure randomized complete block design, with four replications was experimented at Agronomy Research Farm, The University of Agriculture Peshawar. Maize cultivar Azam was sown at the rate of 30 kg ha^-1 with the help of hand hoe in plots having size of 3 × 4.5 m² consist of 6 rows, 3 m long and 75 cm apart. A basal dose of phosphorus (SSP) at the rate of 60 kg ha^-1 was applied before sowing at seedbed preparation. Nitrogen levels (100 kg ha^-1, 130 kg ha^-1, 160 kg ha^-1) and split each nurtured at growth stages i-e GS₁: Full nitrogen at sowing, GS₂: 1/2 N at sowing + 1/2 N V4 leaf stage, GS₃: 1/3^rd N each at sowing+V4 leaf stage+V8 leaf stage and GS₄: 1/4^th N each at sowing+V4 leaf stage+V8 leaf stage+V12 leaf stage with a overall control. Results indicate that nitrogen applied in four splits at growth stages i-e (1/4^th N each at sowing+V4+V8+V12) of maize delayed days to silking took (59), days to tassling (54) and days to physiological maturity (97), ear diameter (3.99 cm), ear length (17.2 cm), ear weight (133.6 g). Among nitrogen, nitrogen applied at 160 kg ha^-1 delayed days to tasseling up to (52), days to silking (57) and days to physiological maturity (95), ear diameter (3.97 cm), lengthen ears (16.5 cm) and bigger ear weight (128.8 g). Conclusively wrap up all main points, elucidate that 160 kg N ha^-1 nitrogen application in four splits could be recommended for maize growers of key region-oriented pickets. The study concludes that applying 160 kg N ha⁻¹ in four equal splits (sowing, V4, V8, V12) significantly enhanced maize growth traits. This nitrogen management strategy is therefore recommended for maize growers in the region to optimize productivity.