Citrus is an important fruit tree, and the harvest of its fruit is inseparable from management techniques. In the growth process of citrus, the extraction and growth period of summer shoots often overlap with the growth and development of fruits, if the extraction amount of summer shoots is too large, a lot of nutrients will be consumed, causing the contradiction between growth and fruit, resulting in fruit shedding and yield decline. Especially for citrus varieties such as sugar oranges, which grow a lot in summer, the protection of the fruit is particularly important. At the same time, summer is also the peak period of citrus pests and diseases, and the growth of summer shoots is easy to increase the probability of pests and diseases, such as anthracnose, canker, citrus psyllid, whitefly, leafminer moth, etc., especially the damage of citrus psyllids may also accelerate the spread of citrus huanglongbing.
Controlling the growth of summer shoots is crucial to protect citrus trees, however, it is often difficult to achieve the desired results with a single tip control technique. Here are some of the traditional techniques for controlling summer shoots:
Artificial pins
This method requires manual erasing or pruning of summer shoots, but this will consume nutrients from the tree, be costly, and be prone to errors in the selection of agricultural time.
Weigh the tips with the fruit
: This method maintains the nutrient balance of the tree by keeping enough young fruit and then pruning and thinning the fruit before the summer shoots are extracted. However, this requires a high level of technical mastery and is prone to pests and diseases, especially citrus huanglongbing.
杀梢素杀梢
: This method uses shoot killing to inhibit the growth of shoots, but it also consumes nutrients from the tree, and sometimes causes the tree to produce so-called "broom branches", which is difficult to control the growth of shoots, and is easy to lead to pesticide damage and problems on the surface of the fruit.
Medication control
: This method uses drugs to control the growth of shoots, but it is susceptible to other factors, resulting in unstable tip control effects.
In order to better control the growth of summer shoots and ensure the health of fruit trees, the following are the best techniques for citrus to control summer shoots and maintain fruits:
Cultivating the Mean Tree Potential
: Make sure that the tree is neither too strong nor too weak to balance the relationship between nutrient distribution and reproductive growth. Too strong will cause nutrients to be used mainly for growth, making it difficult to control the shoots, while too weak will affect the next year's yield.
Weigh the tips with the fruit
: By keeping enough young fruits and pruning and thinning them before the summer shoots are extracted, the tree maintains a dynamic equilibrium of nutrients. This ensures that the fruit has an adequate supply of nutrients, while also inhibiting the growth of summer shoots.
Fertilizer to control the shoots
: After flowering, reduce the application of nitrogen fertilizer to reduce the amount of summer shoot pumping. At the same time, it is important to ensure that sufficient nutrients such as phosphorus, potassium, magnesium, calcium, and boron are provided for fruit enlargement.
Circumcision and circumcision
: Circumcision and circumcision techniques are used to control the growth of summer shoots. This can be done after flowering on the tree, and the growth of the shoots is controlled by cutting off the bark (phloem). These methods produce quick results, but they need to be used with caution to avoid harming the trees.
Medication control
: Certain drugs can be used to regulate the hormone balance of the tree, thereby controlling the growth of shoots. For example, fluthramine (tip capping) is a safer drug that can be used in spring when the shoots are old and in the summer when the shoots are less than 2 cm old. This drug has a longer duration of action and has less effect on fruit trees.
In conclusion, the management of citrus fruit trees requires a combination of factors to ensure the control of summer shoots and the protection of fruits. Through the comprehensive application of various technical means such as cultivating the mediocre tree potential, pressing the shoots with fruits, controlling the shoots with fertilizer, circumcising and ring stripping, and controlling the shoots with drugs, the growth of summer shoots can be effectively controlled and the harvest of citrus can be ensured year after year.