Investigation of genetic variability parameters for <em>Septoria tritici</em> blotch resistance and quantitative traits in bread wheat genotypes

Abstract

Septoria tritici Blotch (STB) is one of the most devastating diseases of wheat in Ethiopia and worldwide. The present study was conducted to assess the genetic variability of yield and yield parameters among different bread wheat genotypes grown under the stress of Septoria tritici Blotch. A total of 180 bread wheat lines, advanced genotypes and released varieties were included in the investigation. Genetic variance, heritability, correlation and ANOVA were estimated for S.tritici, and yield and yield parameters. The genetic variance was relatively high for grain yield, percentage of disease severity (% severity) and Septoria progress coefficient (SPC). Heritability and genetic advance were relatively higher for grain yield, and moderate heritability and high genetic advance were computed for disease parameters such as coverage of pycnidia, Septoria progress coefficient and % severity. A negative correlation was found between plant height and pycnidia coverage on the four uppermost leaves (PCD), SPC and severity. Days to maturity and heading inversely correlated with disease resistance parameters. This indicated that the genotypes having short plant height and short maturity period could be resistant to Septoria tritici Blotch. The results help researchers to utilize the promising genotypes of this study in future breeding programmers for narrowing the yield gaps between the potential and actual in the areas where the Septoria tritici Blotch infection is a problem.

Field response and genetic variability of elite spring bread wheat (Triticum aestivum L.) genotypes for septoria tritici blotch under natural infection in Northwest Ethiopia

“…High and moderate heritability values for disease severity parameters, such as SDSM and SPC, indicate that STB resistance genes are less influenced by the environment. The current result is in agreement with the results of Gerema et al (2020), who reported moderate heritability values for septoria disease resistance.…”

“…Analysis of variance (ANOVA) revealed highly significant variation ( P < .001) between genotypes (G), environment (E), and G × E interaction regarding response to septoria disease severity at heading (SDSH), septoria disease severity at maturity (SDSM), septoria progress coefficient (SPC), days to heading (DH), plant height (PH), and spike length (SL) (Table 1). Similarly, Gerema et al (2020) also reported that the mean squares of septoria disease severity and phenological traits exhibit a great deal of genetic diversity in Ethiopia.…”