Effect of fertilization frequency on cotton yield and biomass accumulation

Cotton is conventionally fertilized with three splits at preplant, first bloom, and peak bloom stages in the Yangtze River Valley of China, but multiple times of fertilization are becoming increasingly more costly. The objective of this study was to determine if one-time fertilization (FI) at first bloom stage with the same amount of fertilizer would produce similar yields to conventional three-split fertilization. A 2-year field experiment was conducted with a compound fertilizer (containing equally 16% of N, P2O5, K2O) of 750 kg ha−1 applied once at first bloom, twice (FII) at preplant and first bloom with 50% each, or thrice (FIII) at preplant (30%), first bloom (40%), and peak bloom (30%). Cotton growth, yield, yield components, and biomass accumulation were examined. FI shortened the cotton (Gossypium hirsutum L.) seedling period but extended the flowering and boll-setting period without changing the total growth period. FI produced similar cotton yield (1328 kg ha−1) to the conventional fertilization treatment, but this yield was significantly higher than that of FII. FI accumulated the same quantity of biomass as FIII. FI had the highest speed in biomass accumulation in both the average (3.28 g plant−1 d−1) and the maximum (3.75 g plant−1 d−1) among the treatments during the fast biomass accumulation period. The results suggest that one-time fertilization at first bloom stage reduced labor costs without reducing the yield, and thus, could be a practical alternative for cotton fertilization.

► Two-year experiment studied effects of fertilization frequency on cotton yield. ► One-time fertilization produced same cotton yield as thrice fertilization. ► One fertilization had higher biomass accumulation speed during fast accumulation. ► One-time fertilization is practical alternative for cotton fertilization.