plant tissue diagnostic tests versus soil testsfieldcrop.msu.edu/uploads/files/tissue diagnostic...
TRANSCRIPT
Not widely used on field crops – annual crops Widely used on perennial crops (tree fruits) – Leaf analysis Sap nitrate tests are used on certain vegetable crops
Plant Tissue Diagnostic Tests
Plant Tissue Diagnostic Tests
Sometimes soil tests are not adequate for diagnosis - tree fruits have large root systems and proper sampling is not possible Most effective in problem solving when both soil and tissues samples are analyzed Rapid plant sampling techniques may be available in the future
Nutrient Sufficiency Ranges
Established for specific plant tissue and specific growth stage
Nutrient Sufficiency Ranges Established for specific plant tissue at the right growth stage
Photo by Tim Boring, MSU
Photo by Tim Boring, MSU
Soil Test Results
Test Good Area Poor Area
pH 6.3 5.6 *
P, ppm 124 124
K, ppm 331 162
Ca, ppm 1166 292
Mg, ppm 151 41 *
CEC, meq/100 g 11.5 5.8*
Leaf Tissue Analysis
Test Good Area Poor Area Sufficiency Guidelines
N, % 3.23 3.21 3.00 – 4.50
P, % 0.33 0.52 0.25 – 0.50
K, % 5.44 4.28 2.00 – 4.00
Ca, % 0.33 0.32 0.25 – 0.60
Mg, % 0.13 0.16 * 0.13 – 0.40
S, % 0.21 0.12* 0.15 – 0.50
Need for Sulfur
• Decreased atmospheric deposition.
• Low organic matter sandy soils.
• Soil tests are not a good guide.
• Tissue analysis is a better guide.
End of Season Cornstalk Nitrate Test
End of Season Cornstalk Nitrate Test
In season plant (tissue) tests are generally used to assess the current soil fertility program and make adjustments next year (unless done very early in the season)
In Season Diagnostic Tests for Field Crops
• No sampling (Non destructive test)
• Need to establish well fertilized N reference plots (side by side comparison)
Chlorophyll Meter as a Tool for N Management
End of Season Cornstalk Nitrate Test
• N03-N accumulate or deplete in the stalk based on soil N availability during the season
• Applied to both conventional and manure fields
• Sensitive to dry and wet seasons * (2011)
• Done 2-3 weeks after black layer is formed in 90% of kernels
