Lodging behavior and yield potential of spring wheat (Triticum aestivum L.): effects of ethephon and genotypes uri icon

abstract

  • Crop lodging is a chronic constraint, commonly limiting irrigated spring wheat yields. Cultivar selection and use of growth regulators are the two factors that can alter lodging incidence to a significant extent. In this study, lodging behavior and yield potential for 16 spring wheat (Triticum aestivum L.) genotypes were studied under disease-free, irrigated conditions at the CIMMYT (Centro Internacional de Mejoramiento de Maiz y Trigo) experiment station near Ciudad Obregon, Sonora, Mexico, during 1997-1998 and 1998-1999. For the conventional planting system, two additional treatments were implemented, one using support nets to eliminate lodging and the other by applying the growth regulator, ethephon, to control lodging. In both years, lodging occurred late (25-30 days after anthesis) but significant grain yield reductions for lodging susceptible genotypes were observed. The Indian cultivar, HD 2329, and the Mexican advanced line, Super Seri, recorded maximum grain yield loss (7.6-8.9%) due to lodging. Ethephon (480 g ha(-1)) application controlled lodging by reducing plant height but also decreased average grain yield by 8.3%, which was primarily associated with a significant reduction in number of kernels per spike. Interaction between management practices (with and without ethephon) and genotypes was significant for grain yield, HI, kernel weight and kernels per spike but non-significant for biomass and spikes per Square meter. Super Seri produced the highest yield across all management practices. This genotype possesses the translocation carrying the Lr19 gene, which likely contributed to its higher grain yield (10-12%) when compared to the near isogenic cultivar, Seri 82, which is devoid of the Lr19 gene. Therefore, the incorporation of this gene into other high yielding semi-dwarf wheat genotypes may enhance wheat yield in addition to providing resistance to leaf rust. (C) 2003 Elsevier B.V. All rights reserved.

publication date

  • 2004
  • 2004
  • 2004