What is RZ2.0 Double Resistance?
Until now, virtually all rhizomania resistant varieties have gained their resistance from one major gene – the Holly gene, first introduced into Europe in the 1980’s.
The new double resistant varieties are different. They incorporate the existing Holly gene with the new C48 gene, which is also derived from the wild beet source Beta maritima, and then introduce this into commercial lines providing the best possible protection against the mutating disease and reducing further spread of the virus.
The mechanism with which the C48 gene provides rhizomania resistance is not completely understood though it is similar to that of the Holly gene and is typically characterised by reduced accumulation of the rhizomania virus in the tap root of the beet plant.
These new RZ2.0 Double Resistant varieties fully utilise both these two major genes – and in addition incorporate minor genes on the same chromosome from both sources which also offers some additional resistance benefits.