Fitossociologia de plantas daninhas em cultivo de beterraba

Abstract

The infestation of agricultural crops by weeds causes serious damage to the producer and the crops, since these plants compete with the crops for water, light, nutrients and physical space, which can lead to a drop in productivity and quality. The objective of this work was to carry out a phytosociological survey of weeds in beet cultivation, cultivated in a direct seeding system in the garden of the Agricultural School of Jundiaí, Macaíba - RN, in order to identify and quantify the weed species. In the survey, a metal square with a side of 0.50 m and an area of 0.25 m² was used, randomly placed in the experiment area, with data collected every seven days, over a period of 49 (forty-nine) days and four repetitions. in each collection. The beet planting was carried out by sowing and the experiment was understood throughout the critical period of the culture, which is approximately six weeks and with data collection being carried out every seven days, that is, (7, 14, 21, 28 , 35, 42, 49), making a total of twenty-eight collections over a period of 49 days. Frequencies, density and dominance were evaluated; absolute and relative, and the importance value index (IVI), which numerically expressed the importance of the main species in the crop, being determined by means of the sum of density, frequency and abundance values, expressed in percentages. Eleven species of weeds infesting the sugar beet crop were identified, distributed in 11 genera and ten families. The most representative family of the entire phytosociological survey, with regard to the number of species, was Poaceae. The survey will enable preventive planning to control existing weeds in the beet crop, helping the producer to reduce costs and environmental impacts.