Períodos de interferência de plantas daninhas na cultura do feijão-macassar (Vigna unguiculata (L.) Walp.).

Abstract

The bean crop is cultivated, for the most part, by family farming, produced by all types of producers with different technological levels in all regions of the country. However, it does not support weed interference, mainly due to competition for light, nutrients and water. The aim of this study was to evaluate the coexistence of weeds in the production of macassar bean (Vigna unguiculata (L.) Walp) and to analyze the interferences in the vegetative and reproductive phases. The experiment was carried out in the municipality of Monteiro (PB), at Sítio Olho D´guinha on the São José farm. For the evaluations in the vegetative phase, 10 plants were selected and marked in each treatment, for the collection of the following variables: plant height, number of leaves, stem diameter, plant leaf area. In the evaluations of the reproductive phase, 10 plants were selected and marked within the useful area of each plot. The following variables were evaluated: pod length, number of pods and flowers, seed weight and yield. For the variables of the vegetative phase, it was found that at 49 days the values found were higher than the preceding periods, with a significant difference between all treatments and variables analyzed, highlighting treatment T2 (21 days of coexistence with weeds) which presented the lowest values for: plant height, number of leaves, stem diameter and leaf area. Regarding the reproductive phase, it was observed that there was no difference between the number of flowers at 56 days. The lowest pod length value was identified in treatment T9 (70 days of coexistence with weeds) at 70 days, when compared to periods that remained for up to 14 days (T0 and T1). For the variables number of seeds per pod and yield, the T0 treatment (7 days of coexistence with weeds) showed the best results. Thus, it was concluded that the longer the coexistence time between weeds and the bean crop, the greater the interference in growth and production characteristics.