Effect of cropping approach and harvest time on yield and sugar content of sugarcane

The effects of cropping approaches, including new-planting sugarcane (in summer and spring ) and ratoon sugarcane, and harvest time, on the yield, quality, and generated income of sugarcane were analyzed using 33-year data collected in Japan from 1975 to 2008. The study shows that the order of the cropping approaches in relation to yield is: summer new-planting sugarcane > ratoon sugarcane > spring new-planting sugarcane. The earlier the planting time of new-planting sugarcanes, the higher the yield is. A quadratic functional relationship exists between yield and first crop harvest time of ratoon sugarcane, meaning that early or too late harvest of the first crop does not favor ratoon sugarcane growth. The more the ratoon times, the lower the yield of ratoon sugarcane is. While sugar content of ratoon sugarcane is usually higher than that of new-planting sugarcane, sugar content generally increases with delayed harvest provided that the harvest time is earlier than late March. Based on the above quantitative findings, mathematical prediction models for the yield and sugar content of sugarcane are established taking into account of cropping approach features. Such models are of great significance for China’s sugarcane industry.