Greenhouse Canada

News
New biocontrol in the Netherlands for tomato leaf miner

November 24, 2010  By Wageningen WUR


WEB EXCLUSIVE

New biocontrol in the Netherlands
for tomato leaf miner

Scientists from Wageningen UR Greenhouse
Horticulture have discovered natural enemies of Tuta absoluta, the
much-feared tomato leaf miner that does not occur in the Netherlands
yet, during research in the Kinderdijk nature reserve in the
Netherlands.

Nov. 24, 2010, Wageningen, NL – Scientists from Wageningen UR Greenhouse Horticulture have discovered natural enemies of Tuta absoluta, the much-feared tomato leaf miner that does not occur in the Netherlands yet, during research in the Kinderdijk nature reserve in the Netherlands.

Advertisement
3596_antonvanderlinden_wur
PHOTO BY AVD LINDEN/WAGENINGEN UR

Scientist Anton van der Linden of Wageningen UR Greenhouse Horticulture
takes a closer look at a tomato plant with eggs of the tomato leaf
miner, that was placed in the Kinderdijk natural reserve as bait for
natural enemies of the leaf miner.

Several of these natural enemies appear to offer new perspectives for biological control of tomato leaf miner.

Tomato leaf miner has its origins in South America where it is a common pest in the cultivation of tomatoes and potatoes. Since 2007 the insect has become a serious problem for tomato growers in Spain and Morocco. Moreover, the affected area was recently extended to cover the entire Mediterranean region.

3596_leaf_damage_wur
PHOTO BY AVD LINDEN/WAGENINGEN UR

The larvae of the tomato leaf miner eat from the leaves while living between the upper and lower cell layers of the leave.

In 2009, the Dutch Food and Consumer Product Safety Authority announced that tomato leaf miner had been detected in the Netherlands, mainly in packaging stations that import Southern European tomatoes.

Dutch tomato growers have recognized the tomato leaf miner as a serious threat and are concerned that the pest’s advance could put cultivation with minimal pesticide residues at risk. Because this type of growing provides a competitive advantage over Spanish and Moroccan growers, the Dutch sector asked Wageningen UR Greenhouse Horticulture and the Dutch Product Board for Horticulture to check whether Tuta absoluta can be controlled by using natural enemies.

3596_parasitic_wasp_wur
PHOTO BY AVD LINDEN/WAGENINGEN UR

A parasitic wasp, depositing an egg next to a larvae of the tomato leaf miner that lives within the leaf.

To find out whether the exotic tomato leaf miner has natural enemies in the Netherlands, Tuta absoluta was used as bait for the indigenous fauna. In order to do so, tomato plants carrying eggs were brought to Kinderdijk, a nature reserve with a wide variety of insects.

Scientists from Wageningen UR Greenhouse Horticulture carried out direct observations of the activity of natural enemies. Before the caterpillars could pupate, the plants were taken back to the laboratory and placed in a cage to collect any possible parasites.

Plants with many caterpillars were shown to work as a magnet for a variety of predators. In addition to “opportunistic predators,” the scientists found a plant bug that attacks the larvae and thrives well on tomatoes. A surprising result was the immediate activity of parasitic wasps belonging to the family Eulophidae that probably originated from related moths.

One of these wasps successfully parasitized and produced offspring. This parasitic wasp is being cultured for identification and further research. If it is shown to be suitable, the scientists will start looking for a related but harmless moth for the production of the parasitic wasps and will develop an effective method to introduce them into the crop

Wageningen UR Greenhouse Horticulture is a leading research institute in the Netherlands for greenhouse horticulture, deeply rooted in both industry and science. As a leader in the development and implementation of innovations, and working in partnership with the greenhouse horticulture sector, it carries out dedicated research into the issues that determine successful business. The goal is to make long-lasting contributions to sustainable and competitive greenhouse horticulture.


Print this page

Advertisement

Stories continue below


Related