Matters needing attention in Sugarcane Irrigation with large Water demand of Sugarcane

Sugarcane has high yield and high water demand. The law of water requirement in the whole growth stage of sugarcane can be classified as "small at both ends and big in the middle". That is, in the budding and tillering stage, the water demand is less, the elongation stage, the water demand is large, and the water demand is also less in the mature stage. Therefore, rational irrigation is helpful to improve the yield and quality of sugarcane. Only by scientifically grasping the water demand of sugarcane in different growing periods can we give full play to the advantage of irrigation to increase production.

Sugarcane irrigation

Sprouting period: water demand is small, accounting for 8.4%-18.1% of the total water demand during the whole growth period, mainly to maintain the ecological water for sugarcane seedling germination to ensure early emergence and full seedling. During this period, it is required to keep the water content of the soil surface layer of about 25 cm cm to 55%-70% of the maximum water holding capacity, less than 55%, timely irrigation, but shallow irrigation is suitable for irrigation, and at the same time, prevent stagnant water in the field to prevent sugarcane seedlings from rotting.

Tillering stage: the plant is small, the leaves are few and small, the transpiration is not large, the water demand is not much, and the water requirement accounts for 15.4%-21.7% of the total, but the drought resistance of sugarcane is weak. At the same time, this period is in the dry season of strong light, high temperature and less rain, sugarcane in the field has not been completely closed, the soil surface evaporation is large, and soil drought will inhibit tillering. Therefore, at this stage, attention should be paid to frequent irrigation and shallow irrigation to keep the water content in the soil surface layer within the range of 30cm up to 60%-80% of the maximum water holding capacity, so as to promote early tillering and early growth of seedlings.

Extension period: it is the key period for the fastest growth and yield formation, with water demand accounting for 54.3%-57.8% of the total. Although this period has entered the rainy season, the row of sugarcane in the field has been closed and the soil evaporation has weakened, but the leaf area index, leaf transpiration and root absorption capacity of sugarcane have reached the maximum. The times and amount of irrigation are determined according to rainfall. In sugarcane areas where there is little rainfall or no rain for a long time, timely furrow or flood irrigation can ensure that the water content in the surface layer of the soil reaches more than 80% of the maximum water holding capacity, so as to ensure the continuous supply of soil water. At the same time, clean up the field drainage and irrigation ditches to prevent the accumulation of water in the field.

Maturity: after entering the mature stage, the elongation growth of sugarcane gradually weakened, the sugar accumulation accelerated, and the demand for water weakened. The number and amount of irrigation needed should be controlled. During this period, avoid flooding irrigation to prevent sugarcane lodging, pay attention to keep the soil surface water content of 40 cm in the range of about 60% of the maximum field capacity, the field surface soil is moist but not wet, dry but not white, in order to facilitate the accumulation of sugarcane sugar.