SummaryBroadening the genetic base of crops is crucial for developing varieties to respond to global agricultural challenges such as climate change. Here, we analysed a diverse panel of 371 domesticated lines of the model crop barley to explore the genetics of crop adaptation. We first collected exome sequence data and phenotypes of key life history traits from contrasting multi‐environment common garden trials. Then we applied refined statistical methods, including some based on exomic haplotype states, for genotype‐by‐environment (G×E) modelling. Sub‐populations defined from exomic profiles were coincident with barley's biology, geography and history, and explained a high proportion of trial phenotypic variance. Clear G×E interactions indicated adaptation profiles that varied for landraces and cultivars. Exploration of circadian clock‐related genes, associated with the environmentally adaptive days to heading trait (crucial for the crop's spread from the Fertile Crescent), illustrated complexities in G×E effect directions, and the importance of latitudinally based genic context in the expression of large‐effect alleles. Our analysis supports a gene‐level scientific understanding of crop adaption and leads to practical opportunities for crop improvement, allowing the prioritisation of genomic regions and particular sets of lines for breeding efforts seeking to cope with climate change and other stresses.

Anthracnose caused by Colletotrichum lindemuthianum (Sacc. & Magnus) Lams.-Scrib. is a major disease affecting common bean (Phaseolus vulgaris L.) crops worldwide. Response to five C. lindemuthianum isolates, classified as races 3, 6, 7, 38, and 73, were analyzed in 156 F 2:3 families derived from the cross between line SEL1308 and cultivar Michigan Dark Red Kidney (MDRK). SEL1308 was resistant to all five races, while MDRK was susceptible to all except for race 73. Segregation ratio for response to races 3 and 7 indicated that single dominant genes were responsible for the resistance reaction to each race. Recombination between both race-specific genes was observed and no linkage was found with any of the molecular markers tagging Co-genes or clusters previously described. Linkage analyses allowed the location of both genes at the beginning of linkage group (LG) Pv03, a region tentatively named as Co-17. Segregation ratio for response to races 6 and 38 indicated that two dominant and independent genes conferred resistance to these races. Contingency tests and subpopulation analyses suggested the implication of one region on LG Pv08, corresponding to the Co-4 cluster, and the Co-17 region. For reaction to race 73, the most likely scenario was that two dominant and independent genes conferred resistance: Co-1 in MDRK and Co-4 2 in SEL1308. Results indicated that, in addition to Co-4 2 , SEL1308 carries resistance genes located at the beginning of LG Pv03, in which no anthracnose resistance genes were previously mapped. In silico analysis revealed the presence of seven genes codifying typical resistance proteins (R-proteins) in the underlying physical position of the Co-17 region.

Powdery mildew can cause severe yield losses in bean crops. Limited information about resistance sources, and nature and inheritance of resistance are available to bean breeders and plant pathologist. Sources of resistance were searched in seedling tests under controlled conditions in 44 well-known genotypes and in a Spanish germplasm core collection consisting on 201 accessions. A 0-4 scale was used to describe the infection types (IT) observed. Only six out of the 245 evaluated genotypes showed a complete resistance (IT0) without visible symptoms on the leaves: Amanda, Belneb, Cornell 49242, Negro San Luis, Porrillo Sintetico and the local accession BGE003161. Inheritance of resistance was studied in F 2 and F 2:3 segregating populations. Observed reactions in the five segregating populations fitted to Mendelian ratios with different modes of inheritance. Results revealed that cultivar Porrillo Sintetico carries two dominant and independent resistance genes: one gene conferring complete resistance (IT0), and another gene conferring IT3, characterized by a moderate mycelial development on the leaves. Both genes show a dominant epistatic relationship. Inheritance of response to powdery mildew in cv. Cornell 49242 was similar to cv. Porrillo Sintetico although the correspondence with the genes described in Porrillo Sintetico was not established. Line X2776 carries one dominant gene conferring IT3, and shares this gene with cv. Porrillo Sintetico. In cv. Amanda, two complementary genes appear to be involved in resistance to this fungus. This information will be relevant for the implementation of breeding programs focused on the development of cultivars carrying genetic resistance to powdery mildew.

Regulation of Sorghum Stem Composition unveiled sorghum MYB and NAC that have not been identified to date as being involved in cell wall regulation. Although specific validation of the MYB and NAC genes uncovered in this study is needed, we provide a network of sorghum genes involved in SCW both at the structural and regulatory levels.