R. M. Junqueira

Desempenho do consórcio entre repolho e rabanete com pré-cultivo de crotalária, sob manejo orgânico

Field experiments were carried out during two consecutive years in the Integrated Agroecological Production System, in Rio de Janeiro State, Brazil, to evaluate the performance of cabbageradish intercropping under organic management on the basis of agronomic traits and Area Equivalency Index (AEI). The contribution of green manure pre-planting to the system also was evaluated. A randomized complete blocks design with seven replicates in a 2x3 split-plot factorial scheme was used. Treatments in the main plots consisted of Crotalaria juncea pre-planting or fallow. Cabbage or radish single crops and the respective intercropping were distributed in the subplots. No significant differences were detected between C. juncea and fallow as related to cabbage or radish yields in any of the systems used (single crops and intercropping). Intercropping had no effect on cabbage yield, but significantly reduced radish root yield. However, commercial standard of the harvested radish roots was not affected. An average AEI of 1,59 for the two experimental years was attained, thus indicating the viability of the cabbage-radish intercropping. The system makes possible to afford additional income for a given area cultivated with cabbage, at its conventional single-crop spacing, by including radish as a secondary crop. Intercropping also was advantageous by allowing optimization of cultural practices such as fertilization, weeding, and irrigation.

Soil macrofauna in cover crops of figs grown under organic management

A fauna do solo tem papel importante em sistemas orgânicos, atraves dos seus efeitos na decomposicao da materia orgânica, mineralizacao de nutrientes e condicionamento fisico do solo. Este trabalho avaliou a densidade e a diversidade da macrofauna edafica sob tipos de cobertura do solo em areas cultivadas com Ficus carica L. sob manejo orgânico do solo. A macrofauna foi coletada em areas de 0,25 × 0,25 m e amostraram-se as camadas de material vegetal e solo ate a profundidade de 0,3 m, nos meses de marco e setembro de 2001. Os tratamentos constaram de cobertura viva com grama batatais (Paspalum notatum), cobertura viva de siratro (Macroptilium atropurpureum) e cobertura morta formada por palha de grama batatais. A mais alta densidade da macrofauna e a mais baixa diversidade foi observada em grama batatais, sendo mais de 80% dessa fauna de formigas, o que caracteriza o solo sob influencia desta cobertura como o de mais baixa diversidade funcional e qualidade, comparado as outras coberturas.

Crescimento e produtividade do inhame cultivado entre faixas de guandu em sistema orgânico

Growth and productivity of taro intercropped with pigeon pea hedgerows in organic system under different management was tested in Bom Jardim, upland region of Rio de Janeiro State, Brazil. A completely randomized block design was used with four replicates. The treatments consisted of unpruned hedgerows; hedgerows pruned with the biomass maintained on the soil surface; and hedgerows pruned with the biomass removed from the experimental area. The unpruned hedgerows system was shown to be advantageous by protecting taro leaves against sun burning and keeping the same productivity of the hedgerows pruned system. In addition, it represented an effective way to control weeds, reducing manual labor and costs of organic taro production in which herbicides are not allowed. The legume hedgerows pruned promoted a significant input of organic matter and nitrogen (6.58 t of dry biomass ha-1 and 159 kg of N ha-1) and the recycling of other nutrients, like 20 kg of P ha-1, 136 kg of K ha-1, 64 kg of Ca ha-1 and 16 kg of Mg ha-1.