It goes without saying that weeds are unwanted in any fruit grower’s field. Weeds not only can impede the growth of the plant, they also have an impact on crop quality and yield. To help growers do their jobs, what do crop protection companies look for when developing herbicides? What are growers’ weed control needs and what steps do they need to take to avoid resistance issues?

To answer those questions, we spoke with BASF’s Brandie Penrose, technical marketing specialist for the new Treevix herbicide, which is powered by Kixor technology.

We also talked with David Warman, director of sales at Marrone Bio Innovations, the supplier of GreenMatch, an organic herbicide made with the active ingredient d-limonene. Below are their responses.

• For the latest herbicide and label change information, click here.

Brandie Penrose

David Warman

Brandie Penrose: At BASF, we are looking for products that meet growers’ pest control needs while delivering excellent crop safety. Before we bring a product into the market, extensive efficacy and crop tolerance studies are conducted to define the optimum use pattern. Treevix herbicide has demonstrated excellent safety and broad spectrum broadleaf weed control in this rigorous tree fruit testing program. Sharpen and OpTill herbicides, also powered by Kixor, have demonstrated excellent safety and broad spectrum broadleaf weed control in the rigorous testing program for chickpeas and dry field beans.

David Warman: In the area of organic production, growers have a limited number of tools so weed control is a big factor when converting from conventional to organic. GreenMatch is a new, effective burndown product that is segmented for organic production. Our company looks for speed of control and the spectrum of weeds controlled when we develop herbicides. Also, we consider the length of time that the product will control weeds. An herbicide must be environmentally sound in order for our company to consider it for our product line.

Q: What do growers tell you they need in an herbicide?

Penrose: Growers are asking for a good broadleaf weed control product. They also are saying that they need more tools for resistance management. There are a lot of weeds that are glyphosate resistant. For many growers, that is the only herbicide they are using.

Growers need to minimize resistance issues and use integrated weed management programs. What that means is that they need to use products with different modes of action. Kixor controls a broad spectrum of broadleaf weeds including those that are resistant to glyphosate, the triazines, and ALS inhibitors.

Warman: Performance and crop safety are critical factors that growers evaluate in an herbicide. Cost per acre is another big factor for growers.

Also, will it go into the ground water? Growers need to keep a clean water supply.

Q: The Weed Society of America recently came out with a report indicating that nine weeds are resistant to glyphosate. What do growers need to do to minimize resistance issues?

Penrose: If growers don’t switch out their chemistries and use other products, such as Kixor, then resistance problems will continue to develop. With nine weeds currently resistant to glyphosate, that number will continue to rise unless growers use products with different modes of action.

To help combat resistance issues, BASF has options in the pipeline that will be coming out in the next five to 10 years to help minimize these problems.

Warman: Any time you have a cropping system where you use one active ingredient over and over again, the chance of resistance is very high. That is what happened with glyphosate. To avoid this problem, different classes of chemistry must be used and active ingredients must be alternated.

Several years ago, there were a few weeds resistant to glyphosate. Now we have nine. We will likely see more resistance problems. Marrone Bio Innovations is actively developing new herbicides with new active ingredients that will address resistance issues as well as other unmet market needs.