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Core Ideas Manual pollinations in breeding and genetics research requires pollen available when recipient silks are viable. The method collects and stores maize pollen for at least 5 days and facilitates efficient pollination. Pollen is mixed with polyetheretherketone and uses field‐collected pollen and simple storage conditions. The method can increase the number of pollinations per tassel and generates a reasonable number of viable seeds. 

Abstract Plant breeding relies on the presence of genetic variation, which is generated by a random process of mutagenesis that acts on existing gene pools. This variation is then recombined into new forms at frequencies impacted by the local euchromatin and heterochromatin environment. The result is a genetic lottery where plant breeders face increasingly low odds of generating a “winning” plant genotype. Genome editing tools enable targeted manipulation of the genome, providing a means to increase genetic variation and enhancing the chances for plant breeding success. Editing can be applied in a targeted way, where known genetic variation that improves performance can be directly brought into lines of interest through either deletion or insertion. This empowers approaches that are traditionally difficult such as novel domestication and introgression of wild accessions into a germplasm pool. Furthermore, broader editing-mediated approaches such as recombination enhancement and targeted random mutagenesis bring novel ways of variation creation to the plant breeding toolbox. Continued development and application of plant genome editing tools will be needed to aid in meeting critical global crop improvement needs. 

Summary The ability of plant somatic cells to dedifferentiate, form somatic embryos and regenerate whole plantsin vitrohas been harnessed for both clonal propagation and as a key component of plant genetic engineering systems. Embryogenic culture response is significantly limited, however, by plant genotype in most species. This impedes advancements in both plant transformation‐based functional genomics research and crop improvement efforts. We utilized natural variation among maize inbred lines to genetically map somatic embryo generation potential in tissue culture and identify candidate genes underlying totipotency. Using a series of maize lines derived from crosses involving the culturable parent A188 and the non‐responsive parent B73, we identified a region on chromosome 3 associated with embryogenic culture response and focused on three candidate genes within the region based on genetic position and expression pattern. Two candidate genes showed no effect when ectopically expressed in B73, but the geneWox2awas found to induce somatic embryogenesis and embryogenic callus proliferation. Transgenic B73 cells with strong constitutive expression of the B73 and A188 coding sequences ofWox2awere found to produce somatic embryos at similar frequencies, demonstrating that sufficient expression of either allele could rescue the embryogenic culture phenotype. Transgenic B73 plants were regenerated from the somatic embryos without chemical selection and no pleiotropic effects were observed in theWox2aoverexpression lines in the regenerated T0 plants or in the two independent events which produced T1 progeny. In addition to linking natural variation in tissue culture response toWox2a, our data support the utility ofWox2ain enabling transformation of recalcitrant genotypes.