Intercropping systems of cowpea with radish are beginning to be deployed in the semiarid region of Rio Grande do Norte state. The great challenge is to know whether or not there is productive efficiency in these systems when fertilized with organic matter produced by spontaneous species from the ‘Caatinga’ biome. Thus, the aim of this study was to evaluate the productive performance of cowpea-radish intercropping systems under different amounts of rooster tree biomass incorporated into the soil. The study was conducted at the experimental farm Rafael Fernandes, rural zone of Mossoró, RN, in the period from June to September 2013, in an experimental design of randomized blocks with four treatments and five replicates. The treatments consisted of the following amounts of rooster tree biomass incorporated into the soil (10, 25, 40 and 55 t ha-1 on a dry weight basis). The best productive performance of the cowpea-radish intercrop was obtained when the rooster tree biomass amount of 50.01 t ha-1 was incorporated to the soil. The use of rooster tree biomass as green manure is agronomically viable in intercropped systems of cowpea-radish.

Removal of the first female inflorescence in corn induces the plant to produce new inflorescences, which allows the first ear to be harvested as baby corn and the second to be harvested as green or mature ear (dry corn). The objective of this study was to compare the following production systems fertilized with nitrogen levels (0, 80, and 160 kg ha -1 ), applied to corn hybrid AG 1051: baby corn harvesting (BC); green ear harvesting (GC); mature ear harvesting (DC); and harvesting of the first female inflorescence as baby corn + harvesting the other ears as green corn (BC + GC) or as dry corn (BC + DC). A randomized complete block design with split-plots (nitrogen in plots) and nine replicates was used. The BC system provided higher baby corn yields than the BC + GC or the BC + DC systems. For all traits employed to evaluate green corn yield, the GC system provided higher yields than the BC + GC system. The BC + DC system provided lower grain yield than the DC system. The application of nitrogen provided increases in all traits evaluated, except for number of kernels ear -1 and 100-kernel weight. The revenue (total and additional total) and additional profit values, in descending order, were obtained with the BC, BC + GC, BC + DC, GC, and DC systems, for all nitrogen levels. The values for those measurements increased as nitrogen dose increased. At the dose of 80 kg N ha -1 , the highest profitability index (percentage of additional revenue that is converted into additional profit) was obtained from DC sales. However, with the application of the highest nitrogen rate, the highest profitability was obtained from BC sales.

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