Micro-Mechanization to Manage Weed in Sugar Cane

Micro-mechanization is a promising method for limiting herbicides in sugarcane. Three experimental trials were carried out to assess the effectiveness and impact on yield of 4 inter-row weeding tools between 2017 and 2021 in La Reunion (a rotary slasher, a mower shredder, a power harrow, and a duck-foot cultivator). Mechanical inter-row weeding allows us to reduce the treatment frequency index by 50%. To assess the effectiveness of the tools, we analyzed the difference in weed ground coverage (ΔCOV) before and after an intervention (weeding). Between 0 and 30 days, the efficiency of the tools was comparable to chemical treatment, with an average efficiency of 70%, except for the duck-foot cultivator in ratoon (ΔCOV = 20%). After 30 days, ΔCOV was negative for the tools studied (power harrow and mower shredder), reflecting weed contamination of the plot, in contrast to chemical weed control (ΔCOV = 81%). Yield analysis showed a significant drop of 10% for the rotary slasher and/or the mower shredder compared with the reference control. An overall downward trend was observed for the other modalities (5%), but further studies are needed to assess their impact.