Bean rust resistance and yield of black bean genotypes under field conditions

Resumen

Objective: To identify black beans lines resistant to bean rust under field conditions, which have similar or higher yield than three commercial varieties sown in Veracruz, Mexico.

Design/Methodology/Approach: The genotypes were evaluated using a completely randomized block design. The reaction of the genotypes to bean rust was qualified using a 1-9 incidence rate, while grain yield was estimated in kg ha^-1. An analysis of variance was carried out and the resulting means were divided using a 0.05 Least Significant Difference (LSD). Additionally, a correlation analysis between the incidence values of bean rust and the yield of the genotypes was carried out in each evaluation site.

Results: Nine lines were resistant to bean rust (incidence average: 1.78-3.33). Out of these lines, Jamapa Plus/XRAV-187-3-4-4 was the most productive line, with a 2,183.4 kg ha^-1 average yield. This result is statistically similar to the results of the Jamapa Plus/XRAV-187-3-4-1 and Jamapa Plus/XRAV-187-3-1-2 lines and the Verdín variety. In addition, the results of Jamapa Plus/XRAV-187-3-4-4 are slightly higher than the results obtained by the rest of the genotypes.

Study Limitations/Implications: Although bean rust was recorded in three of the localities of the study area, the incidence degree and the stage when it was found were different. However, in all the cases, the infection degree was enough to evaluate the reactions of the genotypes to this disease.

Findings/Conclusions: Three bean rust-resistant lines were identified under field conditions. They had a significantly higher average yield than the Negro Jamapa and Negro Medellín varieties.