Current University of Arizona recommendations require periodic stein NO₃-N tests to determine nitrogen (N) fertility status of wheat crops. Lack of data on the importance of sample handling techniques, plant part selection, grinding criteria and extraction conditions have resulted in a reluctance by some growers and laboratory operators to utilize this test procedure. A laboratory study was carried out to examine factors important in wheat stem tissue analysis for NO₃-N. Sample handling, fineness of tissue grinding, and different extraction ratios were examined to determine their effects on NO₃-N recovery. Detailed partitioning of wheat plants at the 3-4 leaf, joint and boot growth stages was conducted to document which plant part is the best indicator of the N status of wheat. Optimal recovery of tissue NO₃-N existed for stem tissue separated immediately in the field and dried within 8 hours; stem tissue ground to 30 mesh or less and extracted for at least 30 minutes; and when using a sample size of 0.1000 g, in conjunction with 25 ml of extractant (i.e. 1:250 plant tissue to extractant ratio). Partitioning data confirmed current University of Arizona wheat tissue sampling guidelines which suggest sampling of the basal portion of the stem tissue.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/203804 |
| Date | 09 1900 |
| Creators | Knowles, Tim, Doerge, Thomas, Ottman, Mike |
| Contributors | Ottman, Mike |
| Publisher | College of Agriculture, University of Arizona (Tucson, AZ) |
| Source Sets | University of Arizona |
| Language | en_US |
| Detected Language | English |
| Type | text, Article |
| Relation | 370071, Series P-71 |
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