Selectivity of nicosulfuron and foramsulfuron + iodosulfuron methyl sodium to different corn cultivars

Abstract

This work aimed the evaluation of the selectivity of nicosulfuron and foramsulfuron + iodosulfuron methyl sodium herbicides to different Agroeste corn hybrids (AS 1545, AS 1548, S2 709, AS 32, AS 3466 and AS 1533). The trials were arranged in a randomized complete block design with 7 treatments and 5 replications for each hybrid. Herbicides rates (in g i.a. ha^-1) were: foramsulfuron + iodosulfuron methyl sodium: 22.5 + 1.5; 45.0 + 3.0 and 90.0 + 6.0 and nicosulfuron: 30, 60 and 90. Phytotoxicity and the parameters relative to the components of crop production and yield were evaluated. The corn cultivars had differential tolerance to the herbicides; S2 709 hybrid had its yield decreased when foramsulfuron + iodosulfuron methyl sodium was applied at 45.0 + 3.0 and 90.0 + 6.0 g i.a. ha^-1; the AS 1533 hybrid had its yield reduced when foramsulfuron + iodosulfuron methyl sodium and nicosulfuron were applied at 90.0 + 6.0 g i.a. ha^-1 and 120.0 g i.a. ha^-1 respectively.