Fighting Pests that Threaten Root Health

Wideshot of orange growing on a tree in a citrus grove

The root health of Florida's citrus trees is indirectly — though substantially — threatened by a tiny insect less than an eighth of an inch long: the Asian citrus psyllid.

By itself, ACP is not a major concern for growers. But it can transmit a deadly bacteria that causes Huanglongbing (HLB), an incurable disease that has spread across Florida.

"One of the early symptoms of HLB is a 30 to 40 percent decline in root mass," said Mike Edenfield, technical service representative for Bayer. "That makes citrus trees less resilient to a variety of stress factors, from cold spells to drought to lack of nutrition."

Another stress factor? Nematodes, those tiny worms found in the soil that feed on the roots of trees. Citrus groves infested with nematodes can suffer from reduced tree vigor, fruit size and yield, making them especially susceptible to the effects of HLB.

"When a tree has been affected by HLB, any stress factor could cause the tree to collapse and die,” said Roy Morris, technical sales representative for Bayer.

But there is an effective solution — one that may already be a part of many growers’ pest management programs — to help control both ACP and nematodes in citrus groves.

Two Destructive Pests, One Treatment

While there is no cure for HLB, the carrier of the disease can be proactively controlled with an effective systemic treatment such as Movento® MPC insecticide from Bayer.

Movento MPC’s two-way systemic action offers growers an excellent tool for ACP control. The University of Florida found that Movento MPC provided greater control of ACP for a longer period of time on citrus crops than other treatments on the market. As an added benefit, Movento MPC reduces nematode populations in the soil from season to season.

“HLB causes root loss in the trees, and managing nematodes to prevent further loss is a very good thing," Edenfield said.


Cumulative Effect from Back-to-back Sprays

A pre-bloom application of Movento MPC should be applied between December and February to prevent new psyllid eggs from hatching. A second application in March or April provides growers with the greatest benefit to their pest management program. A sequential, post-bloom application during this time lengthens the effect of the systemic properties, providing the greatest value to growers and reducing application trips through the citrus grove.


In trials, Movento MPC was found to provide suppression of dagger nematodes 30 days after a second application and contributed to significantly lower populations 60 days after the second application.

Edenfield explains it as a cumulative effect. “By applying the back-to-back sprays, you’re getting that long systemic activity, which gives you the benefit of suppressing nematodes. That's so important when we’re trying to protect our roots.”

An integrated pest management program utilizing a second application of Movento MPC provides growers the protection they need from ACP, while also suppressing nematode populations in the root system.
And, in today’s environment, protecting those roots has never been more important.

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