RESPONSE OF MAIZE PLANTS TO SIMULATED MECHANICAL DAMAGES

Abstract

The aim of this work was to evaluate either incision or maceration simulated damage in maize. A field experiment was established at Embrapa Maize and Sorghun farm, Sete Lagoas, MG, Brazil. The treatments aimed to simulate cut and crush of the aerial parts of maize plants at V2 and V4 stages. Damages were assessed on grain yield, accumulated dry biomass of aerial parts (leaves, stalks, tassels and stylesstigmas), height of ear insertion, plant height, ear biomass/total biomass accumulated ratio and harvest indexes. Biomass of maize stalk in V4 was significantly different from other treatments. Leaves, tassels and styles-stigmas also significantly differed in V4. Similarity was seen within treatments for height of ear insertion and plant height. The analysis of grain yield revealed dissimilarity between treatments with simulated damage and control. Ear biomass/total biomass ratio and harvest indexes were not different among treatments. Plants submitted to cut and maceration showed decreased accumulated aerial biomass, compared to non-damaged plants. Mechanical damages at V4 stage are more detrimental to corn yield. The damage caused by cut or crush in V2 and V4 stages of maize reduced the grain yield.

Keywords

• Zea mays
• multiple cropping
• dry weight partitioning
• growth stages