Red Fuji Apple Color Enhancing Technology
1. Rational fertilization. Red Fuji apples are hi potassium varieties. Therefore, applying more potassium fertilizer after July will increase the fruit coloring index by 24.4% and the sugar content by 2.4% (absolute value). 2. Foliar spraying fertilizer. When the fruit is near the coloring, spraying 500 mg/kg rare earth solution can color it 12 to 17 days in advance, the coloring index increases by 24.2%, the whole red fruit rate increases by more than 5%, the sugar content increases by 0.9% to 1.6%, and the fruit is increased. The ratio of sugar to acid. Red Fuji started from the leaf stage, spraying photosynthetic micronutrients every 15 to 20 days, and spraying it 3 to 4 times during the whole growth period, which can increase the fruit's coloring index by about 30%. 3. Reflective film under the tree. In early August, one meter of plastic film coated with aluminum foil is placed between the trees on the side of the canopy to increase the reflected light and fully color the inside of the canopy and the lower part of the fruit. The total number of red and half red fruits in the trees treated with retroreflective film accounted for 71% of the total, while only 40% of the unpainted trees. 4. Fruit bagging. Red Fuji apple has a long growing period. It is best to use double bagging, bagging 50 days after flowering, removing the bag 30 days before harvesting, and removing the bag in the evening to prevent the sun from burning the peel of the bagged fruit. All the outer paper bags were removed, and the inner bags were torn into umbrellas for 3 to 5 days. After the fruits were completely adapted to the external environment, all the broken inner bags were removed. 5. Pick leaves, twist fruit, hanging sticks. When the fruit is sunny, the leaves that affect the shade of the fruit must be promptly removed. For the non-colored side of the fruit or the joint surface of two parallel fruit, it should be twisted to the sunny side at the right time. The pillars and hanging sticks should be erected in a timely manner in the later period of fruit growth to prevent coloration due to overlapping, squeezing and sagging of the result branches. 6. Spray. Water spray can wash off the dust on the leaf surface, which is beneficial to the photosynthesis of the leaf. The squirt spray is also conducive to cooling the tree, increasing the temperature difference between day and night, and promoting the accumulation of sugar in the fruit. The fruit is colored fast and bright. From the beginning of September, sunny days from the evening of 5 pm use a clean sprayer to spray fine foggy water to the foliage, the leaves of a clean orchard 1.5 acres of water spray can be 500 kg, leaf dirt can be increased as appropriate heavy dirt The amount of water. 7. Harvest timely. According to the survey, the red Fuji apple harvested on October 5 was 10% lower than that harvested on October 25, 25.2% lower in coloration, 14.9% lower in sugar, and 15.1 lower in sugar-acid ratio. Therefore, the suitable collection period for Red Fuji should be in late October.