EVALUATION SYSTEMS OF ASSOCIATION AND CROP ROTATION OF CORN AND CANAVALIA IN TWO HARVEST TIMES. PANAMA, 1993-94.

Abstract

During two consecutive years, in an experiment in two Panama localities, was evaluated different arrangements and rotations corn and canavalia. The objective was to quantify and characterize the differences in production of association and no association system, also determine residual effect of the sowing of the canavalia in the corn yield of second planting date. The canavalia was planting in the middle of the corn lines in continuos rows (CR) and alternate rows (AR) of simultaneous way to the sowing of thr corn. The theoretical population for canavalia was of 2.2 and 4.4 plants/m², for planting in AR and CR, respectively. The corn was cultivated field to 90 cm between rows and 50 cm between blows, to obtain an average density from 4.4 plants/m². The sowing of the first planting dates was fertilized with 136 kg/ha of 15-30-8 plus 136 kg of urea/ha. In the following sows all the treatments received complete fertilization to the moment of the sowing, except of the farmer treatment that received the second application of urea. The experimental resulkts indicated that the asociation of the canavalia does not affect the grain yield. The dry matter production of the canavalia was greater in the plots of monocultivation in the first planting date, followed by the plots in continuous rows and alternate rows. It vas observed a positive residual effect to let the residues of canavalia of one harvest time to another.