Evaluación de la respuesta de líneas de trigo frente a Puccinia striiformis f. sp. tritici. durante el desarrollo vegetativo y fase de espigado, en la parroquia Licto, del cantón Riobamba, provincia de Chimborazo.

Abstract

The aim of this study was to evaluate the response of wheat lines against Puccinia striiformis f. sp. tritici, causing wheat stripe rust in Licto Parish, Riobamba Canton, Chimborazo Province. The experiment was carried out under a Randomized Complete Block Design (RCBD) with three replications for 39 wheat lines, implemented in small plots (SP) of 1 m2, the variables analyzed were: percentage of sowing emergence, vigor stage, growth habit, plant height, wheat ear size, number of grains/wheat ear, percentage of incidence and severity of the first symptoms of each treatment using the modified Cobb diagrammatic scale, disease progress curve (AUDPC), uredinia and urediniospore characterization at laboratory level, grain size and shape, final crop yield in grams/plot. These variables were subjected to statistical analysis using RStudio software. The results showed different percentages of severity and type of reaction of the wheat lines evaluated being: Enty-94, I70034, Entry-86, I11808, Entry-91, J08050168, Entry-90, J08043022, CDC AUSTENSON, J06022012, Entry-93, VIVAR, Entry-88, with averages established from 90.89% to 95.35%, with higher susceptibility to Puccinia stiiformis f. sp. tritici, while: BENTLEY, CDC KENDALL, CDC MEREDITH, CDC MINDON, CELEBRATION, CONLON, Entry-114, Entry-29, Entry31, Entry-83, Entry-85, Entry-87, Entry-95, I11726, I11730 and J07122022 presented the lowest percentage of severity (0%), adopting a resistant reaction to the disease. It is concluded that the genetic constitution of these lines presents genes: Yr7, Yr8, Yr9, Yr10, Yr31, Yr15, Yr44, Yr44, Yr43, Yr18(ARP), Yr29 gene R adult plant, Yr18, Yr24, YrSP, Yr5, resistant to the different races of Puccinia striiformis f. sp. tritici. Trials in other wheat producing areas are recommended to determine their behavior under different climatic conditions.