Monday, November 13, 2006

The Effect of Semidwarfing Genes in Wheat on Plant Height in Diverse Environment in Nebraska.

Zakaria Al-Ajlouni1, P. S. Baenziger2, Kent Eskridge3, Lenis Nelson2, Guihua Bai4, and Ismail Dweikat3. (1) Univ of Nebraska at Lincoln, 181 Plant Science Bldg, Lincoln, NE 68583-0915, (2) Univ of Nebraska, Lincoln, NE 68583-0915, United States of America, (3) University of Nebraska-Lincoln, Univ. Of Ne-lincoln, Po Box 830712-dep.of Biometry, Lincoln, NE 68583-0712, (4) Kansas State Univ, WGGRC, Dept of Plant Pathology, Manhattan, KS 66506

Semidwarfing genes (most commonly Rht-B1b (formerly Rht1), Rht-D1b (formerly Rht2) and Rht8) modify plant structure; reduce plant height; decrease lodging; and can increase harvest index, biomass, and grain yield in wheat (Triticum aestivum L.). In this study, sixty adapted wheat genotypes that were common to two advanced wheat breeding nurseries; Nebraska Interstate Nursery (NIN) and Nebraska Triplicate Nursery (NTN), were grown in 2004 and 2005 at six locations in Nebraska (Alliance, Clay Center, Lincoln, Mead, North Platte, and Sidney) using an incomplete block design to measure their plant height. The year (Y), Location (L), genotypic (G) effects and their interactions were significant (P<0.05). To determine if the semidwarf genotypes respond differently to the environment, the sixty genotypes were assayed using GA3 and molecular markers to establish the presence of Rht-B1b, Rht-D1b (GA insensitive) and Rht8 (GA sensitive).  The response to the environment was determined using stability analyses using linear regression. Results of this research will be presented.