Sugarcane straw management and its impact on production and development of ratoons

Due to mechanical harvesting large amount of straw is left in the field which implicates modification throughout the agriculture environment. This straw is beneficial for both soil and plant. However, there is no information about the sufficient quantity which can be used to achieve such effects and also whether it can be used in other sectors like electricity and ethanol production. Therefore, a research was designed with the objective to evaluate the effect of different amounts of straw on the development and productivity of sugarcane during the first and second ratoons. Treatments used in the experiment included: burned cane, 0%, 25%, 50%, 75% and 100% (20 t ha−1) of sugarcane straw left on the soil surface. The tested variables included leaf area index (LAI), number, diameter, length and production of stems. Plants were evaluated at 60, 120, 180, 240 and 370 days after harvest (DAH) for the first ratoon and at 60, 120, 180, 240 and 270 DAH for the second ratoon. Replacing burned cane harvest system for soil management with straw promotes the development and productivity of sugarcane ratoons. Field managements with burned cane, total removal of the straw, or keeping 25% of straw result in low number of tillers, leaf area index, stem diameter and productivity of sugarcane ratoons, under water stress conditions. Whereas keeping 50% of straw mulch is enough to improve the growth and yield of sugarcane with drought occurrences, while the remaining 50% can be used for second generation of ethanol production or electricity without damaging the crop yield.