Nine barberry varieties named black stem rust-resistant

Photo: B. thunbergii ‘BailJulia’ Toscana, courtesy Bailey Nurseries 

By Jill Calabro, AmericanHort

APHIS recently announced the addition of nine varieties of barberry to the list of black stem rust-resistant species, including:

• Berberis thunbergii ‘BailAnna’ Moscato
• B. thunbergii ‘BailElla’ Lambrusco
• B. thunbergii ‘Daybreak’
• B. thunbergii ‘BailErin’ Limoncello
• B. thunbergii ‘BailJulia’ Toscana
• B. thunbergii ‘NCBT1’
• B. thunbergii x calliantha ‘NCBX3’
• B. thunbergii x media ‘NCBX1’; and
• B. thunbergii x media ‘NCBX2’

These varieties will be eligible for interstate sale starting March 22, 2016, provided that no adverse comments are received before the comment period closes on February 22, 2016. Adverse comments are those that suggest the rule should not be adopted or that suggest the rule should be changed.

USDA ARS conducted greenhouse studies that determined these nine varieties are indeed rust-resistant and, therefore, will not contribute to the spread of black stem rust, caused by Puccinia graminis. Barberry is considered to be the most dangerous source of primary inoculum in the US for stem rust on wheat, oat, barley, and rye. The stem rust pathogen requires two hosts, barberry and wheat (or other cereal grain), to complete its life cycle. As a result, only rust-resistant species and varieties may be sold in protected states.