Perdas de grãos na colheita mecanizada de arroz irrigado

Abstract

The harvesting operation is one that representing big part in the losses and increase the production costs in irrigated rice culture. So, the study and dissemination of adjustments and optimum speeds used in this operation become of paramount importance, thus differentiating them for each trail system. The present work has the objective evaluate the losses the grains in the harvest mechanizes of irrigated rice in different trail systems and travel speeds. The work was developed in the months of March, April and May of 2014 in the Guará Grange, municipality of the Uruguaiana, with the variety IRGA BR 424. Were evaluated three harvests (John Deere SLC 7200, New Holland TC 5090 e John Deere STS 9670) equipped with a radial trail systems, hybrid and axial, respectively and five travel speeds of the harvester (S1= 1,0 km h-¹ ;S2= 1,5 km h-¹ ; S3= 2,0 km h-¹ ; S4= 2,5 km h-¹ and S5= 3,0 km h-¹ ). The design experimental used was the blocks fully randomized, in factorial plan (3x5), with three repetitions. Every evaluations were made in the same part of the farming, looking up the uniformity of crop conditions, with average humidity of 21%. The experiment demonstrated interaction between variables studied, the harvests present significant differences (P<0,05) for the five speeds, wherein the 3,0 kmℎ-¹ presented higher average loss in three harvests. The optimum speeds are of the 1,0 km ℎ-¹ to 1,5 km ℎ-¹ for the harvest with a radial trail system, up to 2,0 kmℎ-¹ for the harvest of axial trail system, the same can yet of the 2,5 km ℎ-¹ for the harvest of with the hybrid system trail, where the same present values of grain losses within the practical standards considered acceptable, but in adverse conditions the axial system present larger capacity of operability reaching higher travel speeds than others without giving mechanical problems, even showing values greater losses.