Projeto adaptativo e teste de um cultivador-adubador mecânico para controle de plantas daninhas na cultura da mandioca

Abstract

It is crucial for the excellent development of cassava crop that the mechanical operation of soil fertilization and weed control are carried out effectively and efficiently in tractor fuel use. The objective of this work was to carry out an adaptation of a cultivator-fertilizer to obtain greater operational efficiency and energy efficiency, reduce fuel consumption, and ensure good effectivenessin weed control. The adapted cultivator fertilizer was projected with four fertilizer distributor boxes driven by gears coupled to its drive wheels and a set of 13 hoe-rodsfor cutting the soil. Different displacement speeds of the tractor-cultivator and fertilizer-distributor set (3.74, 5.82 and 8.51 km h-1 ) and two depths of soil cut (1 and 2 cm) were evaluated according to a completely randomized design, with treatments arranged in the factorial scheme, with four repetitions. Each experimental unit corresponded to an area of 680 m² (4 cultivator passes x 50 m). The cultivator-fertilizer was put to work in an area of 27.7 ha, when the fuel consumption, the engine running time, the maneuvering time, and the refueling time were measured. The plant height of cassava and the effectiveness of weed control were quantified at zero, 17, 39, and 63 days after the cultivation. The adapted cultivator-fertilizer was successfully designed and built, meeting the need to double the work capacity in cassava cultivation in an area with high levels of weed incidence. The tractor-cultivator-fertilizer set showed better operational and energy performance at the highest operating speeds for cassava cultivation, with the better speed being around 9.3 km h-1 . The cassava variety stood out for the good development of the plants obtained when the operation was carried out with 6.5 km h-1 , responding very well to the cultivation and fertilization process carried out with the adapted implement, regardless of the soil cutting depth. To obtain greater efficiency in the weed control in the cassava crop, the speed of 5.6 to 6.2 km.