In-Field Evaluation of Root Lodging Resistance of Whole Maize Plants.

Abstract

Root lodging due to wind is common in maize production worldwide, and can reduce photosynthetic capacity as well as nutrient uptake, resulting in significant yield loss and seed quality reduction. Lodging also causes harvesting problems, and ultimately increases production costs. Evaluating maize resistance to lodging is thus important for both breeders and researchers, to optimize agricultural practices, enhance breeding strategies, and ultimately develop new maize varieties with improved resilience. Here, we describe a novel procedure to accurately and quantitatively assess the resistance of maize plants to root lodging in the field. In this approach, users measure mechanical properties of maize root systems and estimate the magnitude of the wind force acting on the maize plants to ultimately derive an antilodging index, a measure that thus considers the balance between internal and external forces acting on the plants in the field. The procedure, which focuses on the plant as a whole and not only on the root system, has been successfully used to evaluate lodging resistance throughout the entire growth period, from the V8 growth stage to plant maturity, in different maize genotypes. We also compare the procedure to others in the literature, and discuss its applicability for assessing crop root lodging resistance in breeding and cultivation programs.