Morphological Traits Associated with Lodging Resistance of Spring Wheat (Triticum aestivum L.)

Abstract

Throughout the world, lodging in cereals causes great losses in yield each year. A two year field study was conducted to determine the relationship of morphological traits to lodging resistance in spring wheat (Triticum aestivum L.) breeding lines and to find easily measurable traits related to lodging resistance. A set of 15 breeding lines, representing a wide range of combinations of plant height and lodging resistance, was evaluated. During the first year, 29 morphological traits were measured at two growth stages and correlated with the lodging score. Higher correlations were found for traits measured at anthesis (DC 65) than for traits measured at maturity (DC 92); most of the fresh weight traits correlated better to lodging resistance than did the corresponding dry matter parameters. During the second year the six traits of plant height, stem length, stem diameter, ear weight, stem weight and stem weight per cm were measured at anthesis and correlated with the lodging score. From the pooled data of four experiments, significant correlations between the lodging score and single morphological traits were found for stem diameter and stem weight per cm. Thicker stems and heavier stems (mg per cm) were indicative for better lodging resistance. Stem diameter and stem weight cm−1 explained 48.5 % and 49.7 %, respectively, of the phenotypic variation in lodging resistance. Multiple linear regression equations indicated that 77.2 % of the variation in lodging resistance was based on stem weight cm−1 and on the weight of the ear.

Morpho-anatomical traits of two lowest internodes related to lodging resistance in selected genotypes of Triticum

“…Buckling of lower internodes (stem lodging) is commonly observed in wheat, barley, and oats due to differences in the weight and strength of upper and lower internodes of the stem. In common wheat, traits that are most correlated with lodging resistance are: plant height, stem length, stem diameter, stem and spike weight, stem wall thickness, and mechanical layer thickness (Kelbert et al, 2004a,b;Kong et al, 2013;Wang et al, 2006;Zuber et al, 1999). Recent studies investigated the correlations between lodging resistance and the concentrations of cellulose, lignin, pectin, and protein in the stem (Kong et al, 2013;Wang et al, 2012).…”

“…In common wheat, resistance to lodging is highly correlated with plant height as well as stem diameter, stem wall thickness, mechanical layer thickness, and area of transverse section (Kelbert et al, 2004a;Kong et al, 2013;Wang et al, 2006;Zuber et al, 1999). Higher values of the above traits are indicative of increased resistance to lodging.…”

“…A trait that was particularly correlated with lodging resistance was mechanical layer thickness (R = 1.000). According to Zuber et al (1999), the most important traits of common wheat that should be taken into consideration in breeding resistant varieties are plant height, stem weight per cm of stem length, and stem diameter. Wang et al (2006) observed that plants resistant to lodging are characterized by a larger stem diameter, thicker stem walls at the first internode, and a higher ratio of stem thickness to stem radius.…”

“…The identified characteristics can be used in the process of selecting resistant genotypes. Plant height is most highly correlated with lodging, but other parameters are also analyzed, including the number, length, and thickness of internodes, stem weight, anatomical, chemical, and mechanical properties of stems, and root parameters (Berry et al, 2004;Zuber et al, 1999;Żebrowski, 1992a,b). In plant breeding, screening for resistance to lodging is difficult because this quantitative trait is controlled by many genes, and its expression is significantly influenced by environmental factors .…”

“…The correlations between various plant traits and lodging resistance have been widely studied, but an index of resistance traits that could be used in breeding programs has not yet been developed. In wheat breeding programs, plant height remains the most practical and easily selectable trait for lodging resistance (Kelbert et al, 2004a;Zuber et al, 1999). Lodging resistance should be one of the major goals of minor cereals breeding in Europe.…”