Method for evaluating citrus fruit cracking and use thereof

A method for evaluating citrus fruit cracking, comprising:

• evaluating fruit cracking of a citrus fruit by determining one or more of five indicators,
• wherein the five indicators comprise peel hardness, fruit turgor pressure, fruit cracking site at fruit turgor pressure limit, injected water volume at fruit turgor pressure limit, and cracked fruit proportion index;
• the fruit turgor pressure is a pressure value produced inside a citrus fruit when the citrus fruit cracks due to water injected into the citrus fruit from a central axis of the citrus fruit;
• the fruit cracking site at fruit turgor pressure limit is a site of a crack of a citrus fruit, and the fruit cracking site at fruit turgor pressure limit is quantified by the following scoring manner:
• there is cracking in a peel equatorial plane:
• 5 points, there is cracking between a fruit equatorial plane and a fruit pedicel or a fruit umbilicus:
• 4 points, there is cracking around a fruit umbilicus:
• 3 points, there is cracking at a fruit umbilicus:
• 2 points, there is cracking at a fruit pedicel:
• 1 point, there is a wound on a fruit:
• 0 point, and there is cracking around a needle:
• 0 point;
• the injected water volume at fruit turgor pressure limit is an amount of injected water when a citrus fruit cracks;
• a determination method of the cracked fruit proportion index comprises:
• injecting water into fruits from fruit pedicels of the fruits in an amount 5% to 15% of a weight of each fruit, taking a ratio of the number of fruits in which a peel cracks within 24 h to the total number of fruits in which the water is injected as a cracking ratio Cr after the water injection, and calculating the cracked fruit proportion index with the cracking ratio Cr after the water injection, a score S of a peel cracking site, and a time t when a peel cracks according to a predetermined formula:
• cracked fruit proportion index=0.347×(25−t)×(1+S)×(1+Cr), wherein the score S of a peel cracking site is determined by the same scoring manner as the fruit cracking site at fruit turgor pressure limit, and the time t when a peel cracks refers to a tth h after the water is injected into a fruit;
• the peel hardness, the fruit turgor pressure, and the injected water volume at fruit turgor pressure limit each are negatively correlated with a fruit cracking rate of citrus fruits;
• and
• the fruit cracking site at fruit turgor pressure limit and the cracked fruit proportion index each are positively correlated with a fruit cracking rate of citrus fruits.