Tillage and Herbicides Affect Burcucumber Management in Corn

Abstract

The effect of tillage and herbicide application timing was examined on established populations of burcucumber (Sicyos angulatus L.) in corn (Zea mays L.). The field study consisted of three tillage regimes (moldboard plow/disk, chisel plow/disk, and no‐tillage) and three herbicide treatments: atrazine [6‐chloro‐N‐ethyl‐N′‐(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine] plus the dimethylamine salt of dicamba; 3,6‐dichloro‐2‐methoxybenzoic acid applied preemergence (PRE) or postemergence (POST); and no atrazine plus dicamba (no broadleaf herbicide). Postemergence treatments were applied to 3‐ to 6‐leaf corn and cotyledon to 8‐leaf burcucumber. In two of three field locations, late‐season burcucumber dry weight was approximately 65% less in no‐tillage than in the moldboard plow treatment, while no difference in burcucumber dry weight was observed between chisel plow and no‐tillage treatments. Regardless of tillage system, atrazine plus dicamba applied POST was more effective than PRE applications. Corn grain yield was not affected by tillage treatment, but was higher in both the PRE and POST treatments than in the no broadleaf herbicide treatment. Depth of burcucumber seedling emergence was examined in the greenhouse. Pre‐germinated burcucumber seeds were placed in the soil at 0, 1, 3, 5, 10, 15, and 20 cm deep. Percent emergence was highest in the 1 to 5 cm depth. Less burcucumber emerged from depths of 10 cm or greater or when burcucumber was placed on the soil surface. These data suggest that tillage and herbicide timing can influence burcucumber control.