Use of bacillus thuringiensis in the control of plutella xylostella (l.) in the cultivation of cabbage (Original)

Abstract

With the objective of evaluating the effect of the application of the Bacillus thuringiensis in the biological control of the plague Plutella xylostella (L) of cabbage cultivation, parcels were built with a dimension 20,0 m long by 1,20 m wide; 0,50 m of corridor and 0,30 m high. The cabbage plantation mark among array of 0, 60 on the stonemason and a distance among plant of 0,25 m. Three treatments with Bacillus thuringiensis and a control were used, each treatment with an area of 24 m², with three replies. The plague affectation threshold increased where treatment of the biological product was not applied. It is demonstrated that in the first days after the transplant, the plague infestation index is low, and from 15 days on the plague damage in the cultivation increases, when application of biological means does not exist. It was observed that T 1 (1, 0 ml.m2) was the most effective of the treatments, the one of most agricultural yield and the biggest income of the cultivation with a smaller cost per weight of 0, 37.