Reproducing Brassica oleracea in purity through controlled pollination

A protocol for maintaining genetic purity in Brassica oleracea crops through controlled pollination using flesh flies (Sarcophaga carnaria). Self-incompatible genotypes require spatial isolation or net-protected chambers to prevent pollen contamination. Plantlets are transplanted at the 3rd–4th leaf stage into 10-litre pots with peat:perlite substrate and grown in open conditions until flowering. They are then transferred to pollination chambers in cold greenhouses or field settings. Flesh flies are preferred over bees for their efficiency in small chambers. Larvae (1,000–2,000/week) are reared from commercial sources, with metamorphosis occurring between 13°C and 28°C over 8–18 days, depending on temperature. Adult flies are released when plants flower, with protein feed used to extend lifespan. After pollination, plants are returned to the field for fruit ripening.