University of Kentucky, Lexington, Ky.
Plant physiology (Impact Factor: 7.39). 08/1930; 5(3):413-7.
Source: PubMed
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    ABSTRACT: 1. The effects of soil applications of nitrogen, phosphorus, and potash fertilizers on the soluble nutrient content of potato leaf petioles and on yields of tubers were studied. Rapid tissue tests were used to determine the nutrient content of leaf petioles at successive intervals during the growing season. 2. Soil applications of nitrogen fertilizer at the rate of 80 pounds or 160 pounds per acre approximately doubled the N content of potato leaf petioles and doubled the yields of tubers. The concentrations of soluble P and K2O were found to be inversely correlated with the soluble N content of potato leaf petioles. 3. Soil applications of phosphate fertilizer had no effect on yields of tubers, nor on soluble N content of potato leaf petioles. Under conditions of high N supply, application of phosphate fertilier resulted in significantly higher P content and in slightly lower soluble K2O content of leaf petiole tissues. 4. Soil applications of potash fertilizer had no effect on yields of tubers nor on the soluble N content of potato leaf petioles. Under conditions of high N supply, applicatìon of potash fertilizer resulted in significantly higher soluble K2O content but had no effect on soluble P content of leaf petiole tissues. 5. Under the conditions of this experiment, the maximum yields were obtained when the soluble N content of the leaf petioles at the time of first visible flower buds were 600–700 p.p.m.; the soluble P content was 300–400 p.p.m.; and the soluble K2O was 4200–6200 p.p.m.
    American Journal of Potato Research 25(6):216-224. · 0.95 Impact Factor
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    ABSTRACT: The chemical tissue test for phosphate using the Morgan reagent was examined.The time of extraction was very critical, the phosphate extracted being in linear relationship to time up to four hours. The first extraction (15 minutes) removed phosphate varying from 3 to 21% of the total in the plant, and the total amounts of extractable phosphate in II extractions varied from 20 to 76%. Of the total phosphate extracted, over 60% was inorganic. When the time of extraction was 30 minutes or less, the quantities of inorganic phosphate extracted by the Morgan reagent and by water were materially the same.In applying the test to flax on the fertilized plots on two sampling dates, it was evident that the test did not indicate any response to the inorganic fertilizer treatments, but showed significantly higher values for dung-treated plots. The error of the chemical tissue test was exceptionally high.
    Journal of the Science of Food and Agriculture 04/2006; 2(12):537 - 542. · 1.88 Impact Factor
  • Journal of Plant Nutrition and Soil Science 01/2007; 43(3‐4):152 - 170. · 1.66 Impact Factor


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