Nematodes significantly reduce Tuta larvae

Nematodes significantly reduce Tuta larvae

While the spread of Tuta absoluta continues to seriously damage tomato crops worldwide, Italian greenhouse tomato grower and technician, Vittorio Zoboli, confirms that Koppert’s nematode-based product Steinernema feltiae has significantly reduced these destructive larvae in his crop.

‘This is the first year we have applied Steinernema feltiae and after the first cycle of three nematode treatments, we saw a reduction of Tuta in the crop of more than 80%. The large infestation which was present was reduced and under control, and the application greatly contributed to the condition of the plants,’ says Zoboli who works at Società Agricola Gandini Antonio in Guidizzolo, Northern Italy.

‘We examined several dead larvae under the microscope and observed dozens of parasitic nematodes moving inside them,’ Zoboli continues. ‘After this result, we have kept spraying with nematodes every time there was a new wave of small larvae and the problem never grew big after that.’

Reduction of chemicals

‘Using biological control methods, we have been able to significantly reduce the amount of chemicals used in our greenhouses. Società Agricola Gandini Antonio supplies several high-end supermarkets and we want to offer a constant, safe and sustainable product. As the use of chemicals is under pressure and biological protection methods are positively perceived, vegetables protected with IPM solutions are welcomed by customers,’ Zoboli explains.

Growing with respect for nature

Since the establishment of Società Agricola Gandini Antonio in the 1950s, the company has based its farming methods on criteria that respect the environment and people, and the quality of its product. The company built its first greenhouses in the ‘90s for growing tomatoes using innovative production techniques. ‘Today, this allows us to offer a consistent quality that is safe and sustainable all year round on our 14 hectares of high-tech greenhouses and other production sites,’ Zoboli adds.

Joint search for solutions

‘Since the arrival of Tuta absoluta in our areas, we have had problems controlling this pest chemically in our tomato crops. The problem got worse with the ban on several chemical products, while the demand for produce with low or no residue grew steadily,’ Zoboli explains. ‘For these reasons we conducted tests with various products, including nematodes. Since we were already a Koppert customer for their bumblebees and other beneficials, we decided to use the nematode Steinernema feltiae in the spring of 2020. The results were good and there was no residue.’

Using nematodes systemically

‘We then started using nematodes systematically. We liked the idea of having a minimum impact on the surrounding environment and we wanted to offer safe and sustainable products to our customers,’ Zoboli continues. ‘It is better to use them when the larvae are small in order to maximize their effect. When the moment comes, we apply them 3 times at a 5-day interval. We spray them on the tomato canopy at a dosage of 3 billion per hectare. We prefer to apply them in the evening so that the leaves stay wet for longer and the nematodes have more time to reach their targets. We applied several cycles of treatments in our heated greenhouses between February and May, and we will probably do more this autumn when the Tuta become a big issue again.’

‘Together with Koppert’s technical consultants, we have developed an application protocol which allows us to achieve the maximum effectiveness. The crops are now strong and healthy and the Tuta absoluta is not such a big problem anymore thanks to the comprehensive approach developed with the Koppert experts,’ Zoboli concludes.