Yield and resistance to golden yellow mosaic of tropical black bean genotypes

In the tropical areas of Chiapas, Mexico, bean production is affected by golden yellow mosaic, drought and soil acidity. The objective of this research was to identify bean genotypes resistant to the golden yellow mosaic, with higher productivity than the Negro Jamapa variety, commonly sown in Chiapas. In the autumn-winter of 2019-20 20, an experiment was established in three localities in central Chiapas, 11 lines and three varieties of black bean, including Negro Jamapa, were evaluated. The experimental design was randomized blocks with three repetitions. The incidence of golden yellow mosaic and grain yield were quantified. Data from the three localities were analyzed individually and in combination. Correlation analyses between the incidence of golden yellow mosaic and genotype yield were also performed. The golden yellow mosaic significantly reduced yield at the three sites of evaluation (Villa Corzo, r= -0.562*; CECECH, r= -0.757** and El Gavilán, r= -0.552*). The Jamapa Plus/XRAV-187-3-4-1 line showed the greatest damage from this disease with an average incidence score of 6, significantly higher than those of the rest of the genotypes, while the lines: Negro Citlali/XRAV-187-3-1-6, Papaloapan/SEN 46-7-7 and Jamapa Plus/XRAV-187-3-4-4 and the Verdín variety showed the highest resistance to the golden yellow mosaic, with incidence scores between 1.67 and 3.22, statistically lower than that of the control Negro Jamapa. These four genotypes also obtained average yields that were significantly outstanding (greater than 934 kg ha-1) and higher than that of Negro Jamapa.