Identification and characterisation of resistance against rust (Puccinia allii) in garlic (Allium sp.) germplasm

Abstract

In this work we studied the resistance response against Puccinia allii of 533 Allium sp. germplasm accessions under field conditions. Ten resistant accessions were selected to further characterise the defence mechanisms operative. Histological studies showed a range of defence mechanisms, acting alone or combined, that impeded fungal development at different stages. Some accessions showed prehaustorial resistance. In other accessions, mesophyll cells were penetrated by the fungus, but then hypersensitive response leading to cell death hampered fungal development. In some cases, cell death was very fast and early colony abortion was obvious already by 2 days after inoculation (DAI), whereas in others it was slow being marked only by 6 DAI. The fact that resistant accessions studied showed both pre- and posthaustorial resistance offers breeding opportunities for these traits. © 2011 The Authors. Annals of Applied Biology © 2011 Association of Applied Biologists.