Plant Tissue Analysis: A Method Comparison.

An ideal method for plant tissue analysis should be accurate, precise, use relatively safe materials, work with a variety of plant tissues and nutrients, and be simple to perform. The objective of this study was to evaluate several methods of plant tissue analysis for relative accuracy and precision. Methods evaluated included dry ashing, microwave nitric digestion, nitric hydrogen peroxide digestion, and nitric perchloric digestion. Apple leaves, tomato leaves, wheat flour and corn flour samples all with known elemental concentrations from the National Institute of Standards and Technology (NIST) were digested and analyzed on an ICP OES for iron (Fe), zinc (Zn), calcium (Ca), manganese (Mn), copper (Cu), potassium (K), phosphorus (P), sulfur (S), and magnesium (Mg). Digestion methods showed mixed trends in K recovery based on means, but both nitric perchloric, and dry ashing showed high levels of K recovery. Of these two digestion methods, nitric perchloric had the lower standard deviation. Mean P recovery was similar between digestion methods.