INTERFERENCE OF WEEDS IN THE PRODUCTIVITY OF ORGANIC RADISH

Abstract

Radishes are a vegetable well adapted to tropical regions; however, in organic agriculture, weed interference is one of the main limiting factors to productivity, since their control is predominantly carried out by manual and mechanical methods. In this context, defining the critical periods for controlling these plants becomes fundamental. The objective of this work was to evaluate the periods of weed interference and coexistence on radish productivity in an organic cultivation system. Two experiments were conducted simultaneously, in a randomized block design, with six treatments and four replications. One experiment evaluated the coexistence periods, while the other evaluated the weed control periods during the crop cycle. The periods evaluated in both experiments corresponded to 5, 10, 15, 20, 25, and 30 days after sowing. The seeds of the hybrid radish ‘Novella’ were sown in four rows per plot, with a spacing of 20 cm between rows and 5 cm between plants. Weeding operations were carried out according to the treatments, and samples of spontaneous plants were collected for subsequent drying and determination of dry mass. Harvesting was carried out in the two central rows of each plot to evaluate productivity. The data were subjected to analysis of variance using the F-test, followed by linear and non-linear regression analyses. The coexistence of radish with spontaneous plants resulted in a 62% reduction in commercial productivity in an organic system. The results indicate that the crop should be kept free of spontaneous plants between 13 and 18 days after sowing, and one to two weedings are recommended during this period.