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Fluid Journal : Summer 2015
15 The Fluid Journal Summer 2015 The Fluid Journal • Official Journal of the Fluid Fertilizer Foundation • Summer 2015 • Vol. 23, No. 3, Issue #89 Dr. Julian Smith and Vatren Jurin Phenotypic expression of modern genetic traits another plus. Summary: We are on the threshold of a new era for seed treatment methodology and agronomic application that will routinely include micronutrients to realize maximum nutrient use, pest and disease control, and phenotypic expression of modern genetic plant traits. Our work shows that seed treatment with micronutrients can be a valid component of an integrated total crop production program. In time, we visualize genotypic matching for such programs from germination to harvest by maximizing season- long gene expression. Our early research on the subject of micronutrient seed treatments revealed the following: • It is not a new concept • Most data point to a positive agronomic response • It is not easy at a practical dealer/farmer level • Early-season applications do not necessarily cover entire growing seasons. The seed of most common crop species is a phenomenal physiological capsule equipped with the genetics (DNA) of the next generation, ready to create the next iteration as an identical cultivar or a hybrid. This is a fact that agriculture has been taking advantage of for eons. The mineral content of the seed serves two purposes: • Nutrition to the consumer • Nature’s starter for the next planting. The primary seed proteins (phytin) are phosphate-rich and are the original starter fertilizer. As nitrogen (N), phosphorus (P), and potassium (K) fluid mixes soared in popularity during the 1960s and 1970s to supplement seed reserves, it became clear that early- season or at-planting applications of fluid starters or pop-ups actually hindered yield in certain circumstances. The fluid fertilizers in question were predominantly ammonium polyphosphate solutions. Though highly effective in delivering much needed P to the germinating seed, such a high P content in the immediate root zone reduced zinc (Zn) uptake to effectively retard early growth and subsequent gene expression. At this juncture, the introduction of micronutrients to seed application of starter or pop-up fluids became a fairly widespread practice. However, chemistry prevailed largely over agronomics. Compatibility with fluid fertilizer was an issue. It is a very harsh chemical environment but eventually EDTA and related true, strong chelates became the norm. The original complete starter was born. “Close to the seed but not in damaging proximity” was the new maxim established by Glenn Brandt, Bill Lohry, and other early pioneers of the new “NPK fluid plus micronutrient” concept. Early issues Salt index, free ammonia, and positional availability of the nutrients were all issues with the starter, strip, split regimes that included the early crude (agronomically) micronutrient inclusions. Nowadays, superior chemistry, application, and timing prevail to allow continued use of seed-placed NPK, plus micronutrient fluid formulations, tailored to the crop in question. Another early use of fluid fertilizers with micronutrients and seed gained some popularity in the 1980s, the so-called seed and feed applications. Suspension type fluid Micronutrients Promote Nutrient Use, Pest, and Disease Control ▼ DOWNLOAD NPK fertilizers were mixed directly with the seed (such as wheat and alfalfa) prior to broadcast application via flood jets. Intimate contact of nutrient and seed was thus assured at critical early growth stages of the crop. In earlier and later crop protection developments, micronutrient applications to seed became somewhat of an accidental tourist, yet widely accepted as the progenitor to modern seed micronutrient treatment options for many crops. The inclusion of dithiocarbamate fungicides with seeds to prevent fungal pathogens would include nutritionally significant levels of zinc, manganese, and copper or combinations thereof. Subsequent widespread use of other seed fungicide treatment has perhaps further justified specific micronutrient application to the seed. Seed treatment There is ample evidence that in-season micronutrient applications, combined with a multitude of husbandry and environmental factors, strongly influence the expression of the genes carried by the seed. However, seed treatment with micronutrients has hitherto proved problematic from a widely adopted agronomic perspective. One of the major practical issues of seed treatment lies in the morphology of the seed coat itself. Early seed treatments were mostly fine powder dusts that relied upon static charges to adhere to the seed. Some micronutrient One of many treatments in a constant evaluation of different nutrient combinations, this one showing soybeans with top row containing Manganese and Calcium.