In Focus: Four Questions With Rick Rice - GrowingProduce | GrowingProduce

Editor’s Note: Rick Rice is director of sales and marketing for Plant Health Care. The company provides a broad range of biologically based products, along with technical service to gain the full potential of their product portfolio.

1. Florida Grower(FLG): How common are nematodes in Florida, and are there particular areas that are worse?

Rick Rice: I guess the easy answer is to say that nematodes are found almost everywhere in Florida. They’re present in economically damaging infestations in most fruit and vegetable crops and in most citrus groves. Nematode pests are a contributing factor underlying Florida tomato, pepper, and strawberry growers’ continued emergency-use exemptions for methyl bromide, and they’re a major factor in aldicarb’s continued use in citrus. Because nematode populations thrive best in sandy, well-drained soils, the worst areas for nematodes tend to be the best areas for fruit and citrus production.

A Simple Life

Most species of plant parasitic nematodes have a relatively simple life cycle consisting of the egg, four larval stages, and the adult male and female. Second-stage larvae hatch from eggs to find and infect plant roots, or in some cases, foliar tissues. For most species of nematodes, 50 to 100 eggs are produced per female, while in others such as root-knot, upwards of 2,000 may be produced. Under suitable environmental conditions, the eggs hatch, and new larvae emerge to complete the life cycle within four to eight weeks, depending on temperature. Nematode development is generally most rapid with an optimal soil temperature of 70 to 80°F.

Source: UF/IFAS

2. FLG: What kind of yield or quality loss can occur in citrus under heavy nematode pressure?

Rice: The yield and/or quality loss that can occur in citrus or any other crop depends on both the level of infestation and the level of control achieved. Many studies report citrus yield losses in the range of 10% to 30%, depending on the level of infection. Above-ground symptoms include stunting, slow growth, yellowing, reduced foliage, and reduced fruit size and yield. Damage is greatest when other root-limiting factors such as fungal infections, water stress, or poor growth during early development also impact nematode-infected trees. Regardless of the crop, nematodes are a force multiplier with respect to other crop stresses; they magnify the negative effect of anything else that’s hindering an infected plant’s development.

3. FLG: Does Plant Health Care Inc. have a product to help fight nematodes?

Rice: In the absence of methyl bromide, fighting nematodes is about all a grower can do. There’s really nothing else available to ‘control’ nematodes, but where gas isn’t an option, or to reduce nematode reinfestations following the use of methyl bromide, foliar applications of Employ will reduce nematode populations compared to untreated checks. Employ is a new, environmentally friendly, harpin protein product from Plant Health Care Inc. that acts by initiating a complex defense mechanism in plants, analogous in some ways to a broad-spectrum immune response in animals. This protective response makes treated plants better able to tolerate a wide range of plant stresses, including nematodes. It’s a great tool to add to an existing program, whether that tool is gas under plastic in fruit or vegetables, or aldicarb underneath citrus. When used to complement existing nematode management programs, users should experience reduced nematode populations, increased fruit set, and higher marketable yields.

While the specific mode of action continues to be studied, one theory is that treated plants release an exudate that makes the roots less attractive as a host site for nematode eggs. Even though the mode of action is not yet completely understood, harpin protein’s contribution to reduced nematode populations and improved plant health is so well documented that Plant Health Care backs Employ with a satisfaction guarantee. The Employ satisfaction guarantee is simple; when Employ is used to supplement an existing nematode management program, if a grower is not fully convinced that Employ contributed to reduced nematodes and generally improved plant health, Plant Health Care Inc. will refund the full purchase price paid for the Employ used on the dissatisfied acres.

4. FLG: How important is the Florida market to Plant Health Care Inc.?

Rice: Florida is as important to Plant Health Care as it is to the nation’s food supply. A big part of Plant Health Care’s mission is to demonstrate that the world’s population can be fed using environmentally sustainable products and production techniques. It is clean and friendly, so to be able to launch Employ in Florida on the food that ends up in the kitchen fits our mission like a hand into a glove.