Evaluation of Reactions of Different Wheat Genotypes to Common Bunt (Tilletia Foetida) Using GGE Biplot Analysis

Abstract

Tilletia laevis (syn. Tilletia foetida), the causative agent of common bunt, is a spike disease that negatively impacts global wheat production and quality. This study evaluated the reactions of 50 wheat lines at the preliminary yield stage to bunt disease under artificial epidemic conditions during the 2023-2024 growing season at locations in Antalya, Aydın,Çanakkale, Denizli, Kırıkkale, Kırşehir, Mersin, and Siirt. Field trials were conducted at each location with three replications using a randomized block design. Disease spores were inoculated at a rate of 0.5% onto seeds weighing approximately 4 g. In disease reaction assessments, the number of diseased and total spikes for each genotype was enumerated to calculate the percentage of bunt disease. Reactions of susceptible control genotypes were determined to be between 90-100%, indicating that the results of the study were reliable. Reactions were classified as 0% (Immun), 0.1-10.0% (Resistant), 10.1-25.0% (Moderately Resistant), 25.1-40% (Moderately Susceptible), 40.1-70.0% (Susceptible), and 70.1%+ (Highly Susceptible). Additionally, genotype and genotype-environment (GGE) interactions were analyzed using the GGE Biplot method, which accounted for 97.07% of the total variation. The genotype ranking based on reaction groups generally demonstrated consistency with the GGE Biplot results, and it was concluded that the GGE Biplot method is efficacious for selecting bunt-resistant and stable materials. In conclusion, utilizing the scale to assess the reaction of wheat to common bunt provides reliable results. Therefore, materials identified in the resistant group can be utilized as genitors in bunt disease resistance breeding programs. The results obtained from this study are important in terms of reducing the use of fungicides, in the management with the disease and effectively control the disease agent.