Agronomic traits and yield of organic maize under no-tillage system

Abstract

The no-tillage farming has become a popular practice in Brazil, but problems with weed control and plant nutrition persist under organic production systems. This study aimed at evaluating the agronomic traits and yield of maize, after using different off-season cover crops under two organic no-tillage systems. A randomized block design, with a 7 x 2 factorial scheme, being 7 treatments (weeds; black oat monoculture; sunflower; white lupin intercropped with black oat in rows; white lupin intercropped with black oat by broadcasting; white lupin monoculture; and no cover crop) and 2 cropping systems (maize alone and intercropped with jack bean), and four replications was used. The agronomic traits evaluated were plant height, first-ear insertion height, stem diameter, prolificacy, 1,000 grain weight, grain yield and nitrogen released at 60 days of mulch decomposition. White lupin straw in monoculture and intercropped with black oat release a higher amount of N during the decomposition process and, consequently, these treatments increase maize yield. Intercropping with jack bean within the same row as maize reduces its yield potential under an organic no-tillage system.

Keywords

• Zea mays
• Canavalia ensiformis
• cover crops
• organic fertilization