My past couple of newsletters have focused on the importance of post-harvest applications, given our perennial crops’ need to recover and store nutrients in their woody parts after harvest so they can then access them during early spring growth. The practice of starving our crops until spring and then trying to feed the plant everything it requires at that exact point in time is a ridiculous endeavor. Post-harvest applications are the most important of the entire year, as that is the best time to set the table for a successful next season and keep your crops healthy for the long term.
However, there is another reason that post-harvest applications are of value. We sell two products that supply chitin or of its derivatives. Chitosan is a deacetylated (removal of the acetyl group) derivative of chitin that is naturally present in the fungal cell wall and in crustacean shells from which it can be easily extracted. We harvest our chitosan from shrimp and crab shells. Chitosan has natural defensive properties against fungi, bacteria and viruses as well as abiotic stresses. Chitosan effectively improves the physiological properties of plants and also enhances the shelf life of produce. Now that’s exciting! Here’s a substance with many beneficial properties that includes preserving post-harvest produce.
Chitosan-applied products slow ethylene production and respiration, which leads to less fruit decay and less weight loss. Post-harvest chitosan applications maintain the anthocyanin contents of the fruit or, simply put, it’s flavor profile. In wine grapes, for example, when you reach the peak of the anthocyanin curve, your wine grapes are at their most complex flavor state regardless of the brix reading.
Chitosan also plays a role in the activation of plant defense signaling pathways. That includes the elicitation of phytoalexins, and accelerated phytoalexin accumulation in plants is associated with resistance to diseases caused by fungi and bacteria.
Andaman Ag offers Kyte Gold soil amendment and Pacific Gro oceanic fish hydrolysate, both with chitin. Chitosan has been employed in soil as a plant nutrient and has shown great efficacy in combination with other industrial fertilizers without affecting the soil’s beneficial microbes. It can also improve water retention and function as a chelator and soil conditioner. Understanding how to use substances like chitin for not only post-harvest applications but as an integral part of any crop program is a means to use fewer toxic substances while taking advantage of the many benefits these innovative products deliver to the new world of agriculture.