Fruitlet analysis for better quality fruit at harvest
The mineral composition of fruit at harvest has a major influence on fruit quality, affecting factors such as Bitter Pit, Jonathan Spot, Fruit firmness, Internal breakdown (e.g. Low Temperature Breakdown & Senescent Breakdown), Fruit density, Skin finish (e.g. stalk end russet) and Scald. Fruit storage potential is also directly linked to mineral composition.
There is little or no time to take remedial action on the basis of information obtained from pre-harvest analysis which is usually carried out only 2-3 weeks before fruit is picked Analysis, which allows assessment of fruit mineral status earlier in the season, is of much more practical use to growers and advisors as they will have the possibility of managing inputs to maximise profitability.
Phosyn´s unique database contains the results of analysis from thousands of fruit and fruitlet samples from different varieties grown in many different regions throughout the world. The changes in mineral levels in the fruit as it develops throughout the season have been examined and correlated with fruit weight, specifically by variety where possible. As well as the nature of the relationship, biometric analysis also establishes the strength of the relationship for each nutrient This means that the fruitlet analysis result can be used to calculate the percentage risk that any mineral level measured in the fruitlet will give a level which will be too low, or too high, in the fruit at harvest.
Phosyn´s Megalab program classifies nutrient levels into one of five categories; very low, low, slightly low, OK or high. Appropriate advice is then given on a simple, easy to understand report.
Using the Megalab service. If your fruit is analysed by Phosyn laboratories, results will automatically be entered into the Megalab. If you are using a different laboratory you will need to contact us to make sure that the Megalab service is available.
Taking a fruitlet sample. Make sure that the fruitlets sent to the laboratory are representative of the fruit to be harvested (remember, 1 ha may produce over 250,000 harvested fruit!!). Do not sample fruits less than 30 grammes weight (around 30 mm diameter). Sample at least 30 fruitlets taking one fruitlet per tree. Rotate sampling from north, south, etc sides as consecutive trees are sampled. Do not mix fruit from different blocks and sample only healthy fruit. Remember, the analytical results are only as good as the sample they come from.
Author: John Brooks, Global
Published: June 2000