Estudo experimental sobre o uso de salvinia molesta MITCHELL como Biofertilizante

Abstract

Aquatic resources are one of the biggest factors limiting development in countries like Mozambique. Salvinia molesta is an aquatic weed that contributes considerably to the degradation of aquatic ecosystems. The use of this plant for the enrichment of soils and the consequent increase in agricultural production can be a way of contributing to the improvement of the living conditions of local communities. Thus, the present study aims to contribute to a possible reduction in production costs, through the evaluation of Salvinia molesta's plant material for its possible use as a biofertilizer in plant production, which also constitutes an advantage for aquatic ecosystems, insofar as the removal of aquatic plants such as Salvinia molesta is a measure for the protection of these ecosystems. The work was carried out in the field attached to the greenhouses of the Department of Biological Sciences at the Eduardo Mondlane University in Maputo, between the months of June and October 2006. The same consisted in the production of a biofertilizer, using plant material from Salvinia molesta and product testing resulting in the cultivation of common beans (Phaseolus vulgaris). For this purpose, an area of ​​about 400m2 was delimited, which was divided into two equal pieces, in which bean plants treated with biofertilizer containing Salvinia molesta, with biofertilizer without Salvinia molesta and without application of biofertilizer (Control) were grown. Three treatments were considered, namely: control (0%); the treatment "With Salvinia" (10%, 15% and 29%), in which the plants were subjected to the application of the biofertilizer containing Salvinia molesta and the treatment "Without Salvinia" (10%, 15% and 20%) in which the plants were subjected to the application of the biofertilizer without Salvinia molesta. The growth and dry weight of the roots, leaves and pods and the total dry weight were measured as growth control parameters, in order to determine the TCR, TCA, TAA,% MS, RAF, AEF, RPSR, RPSR / A, RPSF, RPSV and CA, throughout the sampling period. Significant differences were found in TCR, TCA, RPSR, RPSR / A, CAFO, which demonstrates that the biofertilizer based on plant material from Salvinia molesta produces a positive effect on growth of Phaseolus vulgaris. However, none of the parameters showed any difference, the significant ones between the applied doses of the biofertilizer under study (with the exception of% MS), although higher concentrations of the biofertilizer had the general tendency to increase the value of the measured parameters.