Comportamiento del maíz (Zea mays L.) criollo y mejorado en asociación con cultivos de cobertura en dos localidades del Valle de Toluca

Abstract

Behavior of “criollo” and hybrid maize (Zea mays L.) in association with cover crops in two localities in the Toluca Valley. One of the limitations faced by maize growers in highland valleys is weed control, which represents 25% of production costs. However, worldwide, cover crops have proven to be a successful technology to maintain soil fertility and moisture and control weeds. In the Toluca Valley, the use of cover crops in maize has been very limited or nonexistent, and their potential impact on agronomic variables that result in higher yields is unknown. Therefore, the objectives of this study were to evaluate the agronomic effect of cover crops in two maize cultivars in terms of the days to weed emergence, weed abundance, and maize yield with each cover crop. The work was carried out in two localities in the municipality of Almoloya de Juárez, Mexico State. We used seeds of white “criollo” maize and the hybrid “Albatros,” and the cover crop treatments were turnip, red clover, beans, no weed control, and the herbicide 2,4-D with Atrazine. For each treatment, we recorded the days elapsed until the appearance of weeds and the abundance of weeds each month, and at the end of the cycle we determined the maize yield for each cover crop. The data were analyzed using an analysis of variance and Tukey’s test in the program SAS (SAS Institute) Version 9.0. The results indicated that the turnip cover represented an alternative for weed control in both maize types evaluated for both localities, as well as being a dual-purpose crop (cover and forage). The weed abundance was lower than in the control treatment and had a similar effect to the herbicide. The cover crop that stimulated the maize to have the highest yield was the clover, and there was also a lower abundance of weeds in both localities evaluated. In the San Agustín locality, the weeds with the highest abundance were: Sicyos deppei G. Don, Amaranthus hibridus L., Drymaria villosa Cham. & Schltdl., and Festuca arundinacea Schreber, while in the Loma Larga locality, they were: Bidens serrulata (Poir.) Desv., Tithonia tubiformis (Jacq.) Cass, Sorghastrum nutans (L.) Nash, Drymaria villosa Cham. & Schltdl., and Festuca arundinacea Schreber. In both localities and in both criollo and hybrid maize, the earliest emerging weeds were Tithonia tubiformis (Jacq.) Cass, Drymaria villosa Cham. & Schltdl. and Festuca arundinacea Schreber.