RESUMEN
Here, we describe a protocol for in planta delivery of chemical compounds into meiocytes of different barley genotypes not impacting plant fertility allowing to harvest seeds from treated plants. Compound uptake into meiocytes is assessed by determining 5-ethynyl-2'-deoxyuridine (EdU) incorporation. Similar to EdU, other compounds being soluble in an aqueous solution can be delivered in planta before/during meiosis to decipher their impact on meiosis and meiotic recombination.We give practical advice on how to deliver EdU as compound example (delivery via injection or needle and thread, addition of detergents or surfactants to increase compound uptake), how in planta compound delivery can be established for your plant material under specific growing conditions, how to generate and characterize barley hybrid plants, and how to conduct a meiotic cytological study of (treated) barley plants.