News - December 23, 2010

Go-ahead for field test with cisgene apples

Plant Research International has been given the go-ahead to carry out field tests with cisgene apples with resistance to apple scab. The Commission on Genetic Modification (Cogem) announced this in a recommendation to the Dutch environment ministry last week.

Apple infected with scab
Plant Research International (PRI) has extracted a gene from crab-apples that protects the apple tree from scab. Because it is a species-specific gene, Wageningen UR calls this cisgenesis. Scab is a persistent fungus that attacks the leaves and fruit of the apple tree. It is the target of eighty percent of the pesticides used on fruit farms. PRI and fruit variety centre Innova Fruit want to launch a resistant apple on the market. Because of the breeding technique that is used, they need government clearance to do so.

Cogem has declared that the cisgene apple does not pose a danger to humans or the environment. Cisgene apple trees may therefore even be allowed to flower. In previous field tests with transgene apples, the PRI was obliged to suppress flowering. PRI researcher Frans Krens, who applied for the permit is 'pleasantly surprised' by the recommendation. 'Because we will now be able to see from the fruit whether there is any scab in the apple, we can cut a couple of years off the whole process of getting a licence to market them.'
If the minister follows Cogem's advice, Krens expects to need about four years for testing before being ready to apply for a license to market the resistant apple. Using genetic modification, it currently takes about 12 years to develop a resistant variety. And using traditional breeding methods, it takes at least fifty years, says Krens.

Wageningen UR has already developed one scab-resistant apple: the Santana. This variety does not have a big market share, however. The aim now is to make a popular apple such as the Elstar resistant.
Krens is wary of over-confidence. 'It is still a contest between the apple and the fungus. Scab has already been found that has broken through the immunity of the resistance gene. That is why we really need a combination of two to three genes that make an apple resistant. And you can only do that with genetic modification, targeting genes very specifically. That is not going to work with cross-breeding tests.'