DESCOMPOSICIÓN Y LIBERACIÓN DE NITRÓGENO DE LOS RESIDUOS DE CAÑA DE AZÚCAR (Saccharum officinarum L.) COMBINADOS CON EL FOLLAJE DE PLANTAS LOCALES

Abstract

Background: Green post-harvest sugarcane residues (Saccharum officinarum) present low rates of decomposition and N release in the short term when integrated into the production system. Combining S. officinarum residues with the foliage of local plants rich in nitrogen could be an alternative to accelerate the decomposition process of residues with a positive impact on soil conservation. Objective: To evaluate and compare the decomposition patterns and potential release of N to the soil of the residues of S. officinarum variety MEX 69-290, with the addition of different foliage such as Clitoria ternatea, Leucaena leucocephala and Tithonia diversifolia, in southern Quintana Roo. Methodology: The treatments evaluated were the following: Clitoria + MEX 69-290, Leucaena + MEX 69-290, Tithonia + MEX 69-290, and MEX 69-290 (control). The materials were placed in decomposition bags and incubated on the ground in four periods (15, 30, 60 and 120 days), in a completely randomized design. The contents of dry matter, nitrogen and lignin were determined for the initial and remaining material in each period. Results: With the integration of local plants, a significant increase in the percentage of decomposition and release of N was obtained. After 120 days of evaluation, the decomposition values were 71.3, 50.4, 48.1 and 33.5%, for the Tithonia + MEX 69-290, Clitoria + MEX 69-290, Leucaena + MEX 69-290, and MEX 69-290 control, respectively. Likewise, the potential N release values were 98.2, 95.3, 92.9 and 58.7%, for Tithonia + MEX 69-290, Leucaena + MEX 69-290, Clitoria + MEX 69-290, and MEX 69-290 control. The Tithonia + MEX 69-290 treatment had the highest relative decomposition rate (0.009 g g-1 day-1) and a high potential N release rate (0.053 g g-1 day-1), compared to the other treatments. Implications: The integration of N-rich plants can increase the decomposition and release of N from sugarcane residues, with potential in plant assimilation from the first crop cycle, reduce the application of nitrogen fertilizer and increase sugarcane yields. in the region. Conclusion: The combination of S. officinarum residues with foliage of local plants, particularly T. diversifolia, could be considered a viable strategy to accelerate the decomposition process and release of N in residues on the edaphoclimatic conditions of southern Quintana Roo.