Abstract:

This study investigated the yield, nutrient accumulation, and soil nutrient status of sugarcane under different sowing dates, providing a scientific basis for efficient sugarcane production and fertilization. The field experiments were conducted using the sugarcane variety ‘Guitang42’ as test material, with sowing dates on February 20 (T1), March 11 (T2), March 31 (T3), April 20 (T4), May 10 (T5), and May 30 (T6). The effects of these treatments on emergence, yield, nutrient accumulation, and soil nutrient changes of sugarcane were analyzed. The results showed that sugarcane began to emerge within 10-40 days after sowing, and the rate of emergence increased with the delay of sowing date. The plant height, stalk height, stalk weight, stalk nodes, cane yield, and total dry matter accumulation of sugarcane decreased with the delay of sowing date. The cane yields of T1 and T2 were both increased by more than 10.32% compared with other sowing dates, but the differences between T1 and T2 were not significant. Among the six sowing dates, the total accumulation ranges of N, P, and K in sugarcane were 119.71-184.96, 15.23-24.49 and 129.65-196.05 kg/hm², respectively. These nutrient accumulations decreased with the delay of sowing date. However, the differences were no significant between T1 and T2. Across all sowing dates, total and available N, P, and K accumulation in soil increased relative to pre-experiment baselines, with smaller increments in T1-T3 than in T4-T6. The contents of alkali-hydrolyzable N, available P, and readily available K in soils under T5 and T6, as well as alkali-hydrolyzable N and readily available K under T4, increased significantly compared with pre-experiment levels. In conclusion, sowing during February 20 to March 11 favors high sugarcane yield and efficient nutrient utilization, whereas sowing on or after April 20 should apply moderate fertilizer reduction based on the increment of soil nutrient accumulation combined with changes of available nutrient content to improve fertilizer use efficiency.

Key words: sowing date, sugarcane, soil, yield, nutrient