Chemical control of weeds during ex vitro acclimatization of sugarcane seedlings

Abstract

Weed control during in vitro plant acclimatization is one of the activities with the greatest impact on the survival and good development of sugarcane seedlings. The objective of this study was to evaluate the effectiveness of chemical weed control during the acclimatization of seedlings of the CP52-43 cultivar, with the herbicides Dual Gold CE 96 (S-metolachlor) at a dose of 0.5 L ha-1 p.c. and Treflan CE 48 (trifluralin) at 1 and 2 L ha-1 p.c., compared with manual weeding and absolute control of free weed growth. The treatments were distributed in a completely randomized design, with 4 replications and 240 plants per treatment. Principal component analysis showed that herbicide doses were positively and closely related to plant leaf length and weight, and inversely related to weed cover and survival, suggesting that herbicide doses were effective for weed control, but not all herbicides were tolerated by sugarcane seedlings. The most effective treatment was Dual Gold EC 96 at 0.5 L haˉ¹ p.c. applied immediately after transplant, with effective weed control, no affectation of seedling growth, and benefits on total substrate fungal and bacterial CFUs compared to the control without herbicides.

Keywords: Microorganisms, Smetolachlor, Trifluralin, Seedlings