Screening of Amaranthus sp. Varieties for Resistance to Bacterial Wilt Caused by Ralstonia solanacearum

Abstract

Bacterial wilt, caused by Ralstonia solanacearum, is an emerging constraint in amaranth production in Benin. Host resistance is the most sustainable disease control measure. Ten amaranth varieties including A2002, Bresil (B) -Sel, Madiira 2, AC-NL, GARE ES13-7, Madiira 1, UG-AMES13-2, AM-NKGN, IP-5-Sel and a local variety from Benin were screened for resistance to bacterial wilt. The study was conducted in a screen house and in the naturally contaminated open field during a consecutive rainy and dry season using a randomized complete block design with four and three replications, respectively. In the screen house, plants were inoculated by drenching a 40 mL of bacterial suspension containing 108 CFU/mL of R. solanacearum strain NCBI 5 GenBank N° MH397250 at the collar region. The bacterial wilt incidence (BWI) and the area under the disease progress curve (AUDPC) suggested differential reactions of amaranth varieties to the pathogen. BWI and AUDPC were low for UG-AMES13-2, moderate for Madiira 2, AM-NKGN and the local variety and very high for A2002, Bresil (B) -Sel, AC-NL, GARE ES13-7, Madiira 1 and IP-5-Sel. The World Vegetable Center’s UG-AMES13-2 can be considered as first choice, which is resistant to R. solanacearum, and should be scaled up for seed production towards supporting farmers.

Quantitative Trait Loci Mapping for Bacterial Wilt Resistance and Plant Height in Tomatoes

“…A score of 0 represented no disease, a score of 1 was equivalent to one leaf wilting, a score of 2 represented half of the plant wilting, a score of 3 exhibited whole plant wilt, and a score of 4 indicated the whole plant was severely wilted and dead [ 56 ]. The area under the disease progress curve (AUDPC) was calculated as described by [ 57 ].…”

New corn resistant lines to stalk rot disease (Dickeya zeae) in Indonesia

“…Thus, pathogen infections can be suppressed below the economic threshold value. The use of resistant varieties is one of the most widely used options because this method is more effective, safe, and relatively inexpensive (Maheshwari et al 2020;Sikirou et al 2021;Wang and Dong 2021). Assembling disease-resistant varieties can be developed either through selection/screening or crossing (Fetene et al 2020).…”