Plant Analysis

Quantum Efficiency Analysis

Bioscience offers a QEA service to measure photosynthetic efficiency by quantum fluorescence. The test is rapid and non-destructive. If provides information on factors such as water and nutrient stress, herbicide damage and the impact of various chemicals applied to plants. This leading-edge technology helps growers develop and refine crop treatment programs and trouble shoot problems.

 

Leaf Tissue Analysis

Bioscience provides leaf tissue analysis services for the purpose of diagnostic testing, monitoring and yield prediction.  Standard analysis measures the macro elements -Nitrogen, Potassium, Magnesium, Calcium, and Sulfur and the micro elements - Iron, Copper, Zinc, and Manganese. Other analytical tests are available on request. We also routinely measure Sodium as an indicator of possible salt stress. The analysis results come with concise interpretations which include comparison against optimal levels and recommendations for crop improvement.  The average turn-around-time for a standard analysis is five working days.

Leaf Tissue Collection Methods

Take care when selecting plant tissue for testing, since the greatest source of error in plant analysis occurs while sampling.  It's important to collect a mean representative sample, not the biggest nor the smallest plants. Do not select tissue which has been damaged by insects or wind. Careless sampling can lead to a misinterpretation of crop performance.  

When sampling for the purpose of diagnostic testing:

Collect samples from both the affected and non-affected crop areas. 
Sample plants and plant parts of comparable age and growth stage. 
Collect sample when symptoms are first observed, since plants can develop unusual nutritional disorders when exposed to long periods of stress. 

When sampling for the purpose of routine monitoring:

a)  Uniform Crop

Collect a composite sample from the whole crop. 
Sample plant parts of comparable age and growth stage. 
Avoid damaged or diseased tissue. 

For most crops, the standard approach to sampling involves division of the field into roughly four equal parts, and a sampling transect is undertaken in each quadrat and preferably at right angles to the crop rows (Figure 1).  Each sample should comprise one leaf from each of 25 - 50 plants. Remove the leaf and petiole (leaf stem) and place in a paper bag.  

For larger fields, select a small uniform area within each quadrat, and sampling similar to that described above is taken within each area (Figure 2).

When sampling orchards or vineyards, an X type traverse is recommended (Figure 3).

b)  Variable Crop

Collect a composite sample within each uniform crop area, using the sampling techniques outlined in Figures 1 - 3. 
Sample plant parts of comparable age and growth stage. 
Avoid damaged or diseased tissue. 
Sampling Plant Parts

Plant parts most sensitive to changes in nutrient supply are used for analysis.  In general, the youngest fully developed leaves (blades and petioles) are collected. For young plants, collect the entire above-ground plant. For palms, remove a blade from the middle of the youngest fully developed frond.