"TM3 resistance provides less protection"

Breakthrough of TM3 resistance at Dutch pepper grower

In the past growing season, a commercial variety with TM3 resistance was affected by the TMV virus. Tests by Rijk Zwaan confirmed that it involved a new strain of the virus. No effective resistance exists as yet against this particular strain.

Rijk Zwaan received some alarming reports of viral symptoms at a pepper grower in the Netherlands, which occurred in both TM2- and TM3- resistant varieties of different seed companies. At the request of the grower, crop samples were examined by the plant pathological research team of Rijk Zwaan. Tests showed that the entire range (TM0, TM2 and TM3) was viable and that the culprit is a new strain of tobacco mosaic virus. TMV is a positive-sense single stranded RNA virus that infects plants, especially tobacco and other members of the family Solanaceae.

Shared responsibility
A breakout of TM3 resistance had already taken place in Israel, in the Netherlands the new strain surfaced for the first time. In consultation with the grower, Rijk Zwaan has decided to share the news with the sector. "The important thing now is that growers know that a variety with resistance TM3 offers less protection against the TMV virus than previously assumed," says managing director John Coremans of Rijk Zwaan Netherlands. "As pepper sector, we have a collective responsibility to avoid any further spread of the new virus strain as much as possible."

Preventive measures
In practice, this means that growers should continue to follow standard preventive measures that apply in pepper cultivation. This would include the wearing of protective clothing at company visits and the use of milk in crop operations.

Rijk Zwaan continues its research in the matter.

More information:
Rijk Zwaan
Burgemeester Crezéelaan 40
PO Box 40
2678 ZG De Lier.
www.rijkzwaan.nl

Publication date: Tue 21 Oct 2014