Cucumber growers know spring is the key time for thrips and whiteflies to start developing in crops. Biobest IPM & Pollination Specialist – Pascal Briand – explains why a preventative control strategy is best and how to achieve it.
Problem pests
As temperature rises in spring, whitefly populations can increase very quickly causing serious damage to a crop. Female fertility depends on the temperature and the host plant. In cucumbers, one female whitefly can lay up to 200 eggs – at 25°C these can develop into adult in around 21 days.
Western Flower Thrips (WFT) is often a serious problem due to its high rate of reproduction, fast development time and ability to quickly develop resistance to pesticides. While feeding damage is usually visible on crop leaves, this pest also damages the fruits – causing them to distort – leading to yield loss and quality issues.
Stay a step ahead
“To get effective thrips and whitefly control, we recommend a preventative strategy based on the predatory mite A. swirskii,” says Pascal. “This predator actively searches the crop for thrips larvae as well as whitefly eggs and early larva instars. Besides this, a good swirskii population can also help control the first two spotted spider mites to appear in the crop.”
To stay one step ahead, it is a good idea to have a ‘standing army’ of predators waiting in the crop before these pests appear.
Nutrimite
By applying Nutrimite – a 100% natural feed supplement consisting of a special selection of pollen – growers can establish and maintain a swirskii army, at fighting strength, before the pests arrive.
“Nutrimite contributes significantly to the success of this preventative strategy,” explains Pascal. “Highly nutritious to swirskii mites, it increases both fertility and egg laying.”
“Where Nutrimite is applied to cucumber crops we’ve seen the swirskii population double, compared to crops where no alternative food source was applied.”
When and how to feed
Nutrimite has been carefully formulated to support the establishment of a strong predatory mite population in the absence of pests.
“With no pests present in the crop, one application every week or two weeks keeps the predatory mite population in great shape,” says Pascal. “As with all biocontrol strategies, we recommend careful monitoring. Once the pest pressure has reached a certain level, the predatory mites have an alternative food source and Nutrimite™ feeding can be put on hold.”
Added benefits
He goes on to say, “as we continue our research into Nutrimite, we’re seeing it provides additional benefits. For example, it helps reduce intraguild predation – where predatory mites feed on other beneficials, such as Aphidoletes. Beside A. swirskii, Nutrimite is also of benefit to other predatory mites such as Montdorensis-System and Degenerans-System as an excellent food source.”
“With growing experience in a variety of crops and different countries, our advisors are helping growers to fully exploit the advantages of this preventative strategy. Don’t hesitate to call on them for tailor-made advice.”
Biobest