INITIAL TOLERANCE OF THE IACSP95-5000 CULTIVAR: I - PRE-PLANTING HERBICIDES UNDER DIFFERENT PLANTING TECHNOLOGIES

Abstract

The use of pre-sprouted seedlings (PSS) promotes the development of a more robust root system, which may alter the interaction between plants and herbicides and, consequently, affect cultivar tolerance. This study aimed to evaluate the initial tolerance of the sugarcane cultivar IACSP95-5000 under billet planting and different PSS systems to herbicides applied before planting. The experiment was conducted in a randomized block design in a factorial arrangement with four replications, evaluating planting technologies and pre-planting herbicide application. Herbicides were applied 30 days before planting, and phytotoxicity, tillering, plant height, and dry mass were assessed. The mixture of pendimethalin + trifluralin caused greater phytotoxicity, reduced tillering, and lower plant height. It was concluded that the sugarcane cultivar ‘IACSP95-5000’ showed tolerance to imazapyr during early development, up to 90 days after planting (DAP), under all evaluated planting technologies (billet, MPB IAC, Plene PB, and Plene Evolve), when applied 30 days before planting.