2023 Volume 16 Issue 1 Pages 14-20
Three sugarcane cultivars were planted in spring and summer under uncontrollable meteorological disasters, such as droughts and typhoons, and monitored for eight years, each to the first ratooning. Available sugar yields (ASY) and their components affected by meteorological disasters, crop types and cultivars were analyzed, and factors for improving sugar yields in cultivation systems were investigated. Although ASY and its components fluctuated greatly due to droughts and typhoons, effects of crop types and cultivars were also clear. Regarding the stability of components, the available sugar content was the most stable, and the millable cane number slightly stable. However, the millable cane weight and ASY decreased because the stalk weight was affected by drought during the vigorous growing season. Therefore, it was suggested that the stalk weight has great potential to stably increase ASY by improving soil water retention and irrigation during the growing season. The annual ASY was significantly higher in the order: spring planting ratooning system, summer planting ratooning system, and summer planting system. However, cultivation systems should be flexibly selected according to farm scale and labor force. In addition, it is important to select a high-sugar cultivar with heavy stem and high ratoon-ability, and improve fertilization method to stabilize the sugar yield of the summer planting ratooning. New cultivar RK97-14 is recommendable higher ASY in all cultivation systems; however, it is more suitable for a little late summer planting as it is easy to lodge.
