The technique and application of plant tissue tests for the availability of soil phosphate

✍ Scribed by S. H. Yuen; A. G. Pollard

• Publisher: John Wiley and Sons
• Year: 1951
• Tongue: English
• Weight: 443 KB
• Volume: 2
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/jsfa.2740021204

✦ Synopsis

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.