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Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School

Plant Science

First Advisor

R.H. Gelderman


Maximum crop yields depend upon a balanced supply of 16 basic nutrients. throughout the crop cycle. Achieving this balance can often be made easier through plant analysis (Bowen, 1978). Plant analysis can be described in terms of three separate operations: a) sampling of crop fields, b) preparation of the plant material for the laboratory, and c) chemical analysis of the plant material. Sampling is the first important step in plant analysis and less time consuming than analyzing the samples. "If the sample taken is not representative of the commodity from which it was obtained, all the careful and costly work put into the subsequent analysis will be wasted because the results will not be valid" (Steyn, 1961) . An extensive survey of the literature revealed a remarkable lack of published experimental work to statistically determine the number of plants to sample to represent the field. Therefore, the first objective of this study is to estimate statistically the number of subsamples needed for analyzing constituent plant elements in corn (Zea Mays L.) and soybean (Glycine max L.). The results obtained from plant analysis are no better than the care taken in sampling, preparing (cleaning, drying, 7 2 grinding, and. storing), analyzing (weighing, digesting, filtrating, determining) of plant materials. Potential for error can be found at each step of plant analysis. If these error sources are neglected the final results may be flawed. Therefore, the second objective of this study is to determine the relative contribution of field and laboratory sources of error for constituent plant elements in corn and soybeans. This is particularly important in determining where additional time and resources should be allocated to lower the overall variability in a plant analysis program.

Library of Congress Subject Headings

Plants -- Nutrition -- Analysis
Corn -- Nutrition -- Analysis
Soybean -- Nutrition -- Analysis




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