Phytopathological Assessment of Lines of Common Winter Wheat to the Cause of Brown Leaf Rust (Puccinia recondita f. sp. tritici)

Abstract

The study was conducted in the period 2017-2019 in the experimental fields of the Institute of Plant Genetic Resources "K. Malkov” in Sadovo, near Plovdiv, Bulgaria. At the infectious area, the immune responses of twenty-two genotypes of common winter wheat to the causative agent of brown leaf rust - Puccinia recondita f. sp. Tritici were tested The line MX 289/2048 has shown high resistance to the pathogen, and seven samples are characterized by a stable reaction. The biggest share of the studied breeding materials showed average resistance to the phytopathogen. A comparison of the indicators of grain weight in the central spike and 1000 kernel weight was made for samples grown on an infectious site and under natural field conditions. The obtained results showed an exceeding the values of the trait in favor of the samples grown under natural field conditions. It was found that the greatest influence on the traits grainsweight in the central spike and 1000 kernels weight has the year of cultivation. To assess the genetic diversity, a cluster analysis was applied, in which the selection materials were grouped into five main cluster groups. The lines MX 286/1777 and MX 270/3461 are characterized by the greatest genetic proximity, and the line MX 285/1058 is genetically the most distant compared to the samples from the first cluster group.