In Focus: Four Questions With Dante Brunetti
1. Florida Grower (FLG):What is systemic acquired resistance in plants, and why is it important?
Brunetti: Systemic acquired resistance (SAR) is a phenomenon whereby the plant is induced to manufacture greater-than-normal amounts of defensive substances that would include proteins such as chitinases, glucanases, defensins, peroxidases, etc. (collectively termed pathogenesis-related proteins). In simple terms (and grossly understated), for example, when KeyPlex 350 is applied to a citrus tree, it elicits defense mechanisms, e.g., the salicylic acid response that will, in turn, induce the tree to produce higher levels of pathogenesis-related proteins. These defensive proteins can be enzymes that fend off diseases, and perhaps some insects. Because KeyPlex has no direct inhibitory or toxic effect on plant pathogens, it doesn’t promote resistance in the pest, whether it is a pathogen or insect pest.
2. FLG: What role do biological elicitors such as alpha-keto acids play in plant defenses?
Brunetti: Elicitors trigger plant defensive mechanisms. Different elicitors trigger different defenses. In nature, plant defenses can be passive (for example, cell walls and cuticle) and active (enzymes such as chitinases that directly attack chitin-containing pathogens). Many of the active defenses are triggered by pathogen-infection processes that are sensed by the plant. Elicitors contained in KeyPlex materials can turn on these active defense mechanisms so that the plants have a higher level of defense. It is important to use elicitors in combination with plant nutrients such as those found in KeyPlex.
3. FLG: How has the demand for products with good environmental profiles grown in recent years?
Brunetti: Government regulation fueled by public sentiment has created a demand for safer, eco-friendly agrichemicals, be they fertilizers or crop protection chemicals. The grower, too, must be satisfied that the input to his crop is safe for the consumer and the environment. In the descriptive verbiage of its approval of KeyPlex 350 in the Federal Register, the EPA used key words such as, “safe,” “biodegradable,” “non-toxic,” etc.
4. FLG: Has the market for plant nutritionals been hit by volatility like the markets for N, P, and K?
Brunetti: In a word, yes. Two primary factors worked in concert to force the price of plant nutritional supplements to escalate. First, there was an unprecedented spike in the cost of raw materials as China’s seemingly insatiable need for metallic salts increased in the months prior to the 2008 Summer Olympics. Second, as petroleum prices rose in late 2007 and most of 2008, this helped the cost of raw materials to rise, but it also caused the price of plastic containers to climb steadily through the period in question. This was a situation that kept manufacturers, blenders, and growers off balance as prices changed almost daily.