Comparison of local and exotic maize varieties for stalk lodging components in a desert climate

A 2-year study on the influence of certain plant morphological traits as well as the chemical composition of the stalk on lodging in exotic and local maize groups was done at Sultan Qaboos University. The exotic group consisted of six varieties, while five varieties were represented in the local group. The soil type was classified as saline, the EC being 3.9-4.2 dS/m. In both maize groups, lodging was negatively correlated with grain yield, rind thickness and stalk breaking strength. Weight of 5-cm stalk section was negatively correlated with lodging in the local group but the exotic group showed no such correlation. In the exotic group, lodging was positively correlated with ear height and negatively correlated with stalk lignin and total nonstructural carbohydrate (TNC) concentration but no such correlations were represented in the local group. In a stepwise regression analysis, a four-variable model consisting of shelling percentage, stalk breaking strength, rind thickness and TNC had a coefficient of determination (R-2) of 0.66, suggesting that 66% of the variability in lodging was due to variability in these characters acting together. Based on this result it was suggested that, in breeding for lodging resistance in maize in a desert climate, it may be worthwhile to focus on these four parameters. (C) 2003 Elsevier B.V. All rights reserved.