After the citrus enters the coloring period, it is necessary to do a good job in the management work, so that it is fully colored, the color is bright, and the taste is sweet and delicious, so as to effectively improve the commodity value of citrus. However, if you encounter a slow coloring and low sugar of citrus fruits in this period, how to solve it? Let's take a look.
1. Improve lighting
Good light conditions are conducive to carbohydrate synthesis, promote sugar accumulation, promote the synthesis of pigments such as anthocyanins and carotenoids, and are conducive to coloring. Therefore, at this time, it is necessary to strengthen the management of the canopy, rational pruning, and improve the ventilation and light transmission conditions of fruit trees. Pay attention to sawing off the upright branches in the center to let the sunlight in, and the large branches with too small branching angles and the branches that intersect and are vertical should also be properly pruned.
2. Reasonable fertilization
After citrus enters the flavor formation stage, attention should be paid to nitrogen control, increase the application of phosphorus and potassium and medium and trace elements in fertilization. Phosphorus can improve photosynthetic energy efficiency to promote fruit ripening, potassium can improve fruit sugar accumulation, promote coloring; medium and trace elements molybdenum can promote the synthesis of organophosphorus compounds in plants, participate in photosynthesis and respiration in the body and promote fruit sweetness and color.
3. Foliar spray fertilizer
Foliar fertilizers such as potassium dihydrogen phosphate + calcium magnesium + amino acids + amino acids or alginic acid are sprayed on the foliar surface to supplement the fast-acting coloring nutrients, which is conducive to sweetening and coloring the fruit.
4. Scientific water control
Scientific water control can also improve the soluble solids and sugar content in the fruit juice and improve the quality of the fruit. In general, the specific water control time for citrus is 20-30 days before harvesting. The water control method can be to cover the ground with reflective film, which can control both water and fill the light, and improve the efficiency of citrus sweetness and coloring.
5. Temperature management
Appropriate low temperature can accelerate the decomposition of citrus chlorophyll and increase the synthesis of anthocyanins and carotenoids. For low-temperature areas and the transcolorization period of late maturing varieties, low temperature at night can reduce respiratory intensity, increase sugar accumulation, weaken protein synthesis, and promote pigment formation.
6. Rational use of hormonal agents
Hormonal agents must be used scientifically to avoid abuse. Generally like brassinolide, amine fresh ester to promote citrus coloring than ethylene, abscisic acid safety, the effect is good.
In general, the coloring and sugaring of citrus will be affected by many factors, and the management of citrus that has entered the coloring period should focus on the improvement of the light and temperature environment and the management of water and fertilizer. Of course, pest control is also essential, otherwise it will directly affect the sugar accumulation and discoloration of the fruit.