Achieving sustainable agricultural systems will require transformative changes in markets, policies, and science.

Wild Phaseolus vulgaris L. accessions containing arcelin codominant alleles 1 through 5 were reconfirmed and characterized for resistance to the Mexican bean weevil, Zabrotes subfasciatus (Boheman) (Coleoptera: Bruchidae). Accession G 02771 (arcelin 5) had the highest level of antibiosis resistance, followed by G 12952 (arcelin 4), G 12882 (arcelin 1) and G 12866 (arcelin 2). Arcelin 3 accessions conferred the lowest levels of resistance. As the presence of arcelin is inherited as a single dominant gene, a backcross breeding program has been used to transfer resistance to the Mexican bean weevil from wild beans to bean cultivars using serological techniques to detect the presence of arcelin and replicated insect feeding tests to measure resistance levels. Progeny containing arcelin 1 showed resistance equal or superior to that of the resistant check. Arcelin 2-derived lines had intermediate levels of resistance while no resistant progenies were obtained from crosses with arcelin 3 and 4 sources. Results are discussed in relation to the deployment of arcelin alleles in bean cultivars.

Arcelin, a seed protein discovered in wild Phaseolus vulgaris L. accessions, gives high levels of resistance to the Mexican Bean Weevil [MBW; Zabrotes subfasciatus (Boheman)]. Five arcelin variants have been described. To better understand the genetic control of arcelin and MBW resistance, an inheritance study was conducted. Bioassay tests for insect response, and biochemical lasts to detect the presence‐absence of arcelin, were performed on the same individual seed. Accessions G12952 (arc‐4) and G02771 (arc‐5) had the highest level of resistance to MBW with no adults emerging from infested seed. Resistance was also found in G12882 (arc‐1) and G12866 (arc‐2), while G12922 (arc‐3) and the commercial cultivar, Pijao, were susceptible to the insect. The genetic study confirmed that all arcelin variants were inherited as a single dominant gene based on biochemical evaluations for presence‐absence of arcelin. Nevertheless, in bioassay tests with MBW, only crosses with arc‐1 and arc‐5 showed a single, completely dominant gene mode of inheritance, with the presence of arcelin being highly associated with resistance to the insect. For arc‐1 and arc‐5, biochemical tests can be reliably used to select for MBW resistance. For arc‐2, a combination of biochemical and bioassay tests is needed. As arc‐4 segregated few resistant individuals, and arc‐3 gave only intermediate to susceptible offspring, the use of these two arcelin variants is not recommended in a routine resistance breeding program. Electrophoretic patterns and bioassay tests of F1 and F2 generations showed that arc‐5 and arc‐1 variants are inherited as a single unit and are codominant.

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