Introduction to planting time of Citrus and Control techniques of Diseases and insect pests in Spring

When it comes to citrus, I believe everyone is no stranger, it is a kind of fruit that many people like, there are many kinds of fruit, such as sugar orange, mandarin orange, fertile orange, green orange, ugly orange and so on. Citrus is cultivated all over China, especially in the south. Let's take a look at the introduction of citrus planting time and spring pest control techniques.

First, the planting time of citrus

1. Spring planting: spring planting should be carried out from February to March and before and after spring shoots germinate. When the temperature rises in spring and the rainy season comes, the survival rate of citrus planting is generally higher. however, due to the restoration of branches and leaves before taking root, the tree is bound to be weak, the annual growth is small, and its growth condition is not as good as that of autumn seedlings.

2. Autumn planting: after the autumn shoot stops growing, the air temperature decreases, but the soil temperature is still high, the citrus branches and leaves no longer grow, but the roots still grow once. Therefore, planting at this time can reduce a large amount of water demand for branch and leaf growth, and the tree body consumes less water. After planting the tree, the root system can continue to grow and restore the water supply capacity in time, which is an ideal planting time. However, if there is a threat of low temperature and freezing in winter, it is not suitable to be planted in autumn, but should be planted in spring.

2. Introduction of pest control techniques of citrus in spring.

1. Scab

Occurrence regularity: when it is rainy in spring and the temperature is more than 15 ℃, the overwintering pathogen produces conidia and invades new tissues. Scab can spread rapidly after moderate rainfall and temperature rise.

Prevention and control methods: seize two key periods of spraying to protect citrus shoots and young fruits. One is the sprouting of the spring bud, the first time the bud is sprayed when the bud grows a grain of rice, and the other is the second time when the flower falls at 2/3. In case of cloudy and rainy weather, the effect of pesticide application is not good, but also in the early May young fruit period spray again.

Medicament selection: difenoconazole, tebuconazole + mancozeb, etc.

2. Anthrax

Occurrence regularity: it generally occurs in April to June every year, causing fallen leaves, flowers, fruits and branches to die. Especially in the case of more continuous rain in spring, it is a favorable period for the spread of conidia, resulting in a large area of orange orchard damage.

The disease also has the characteristics of latent infection, spring shoots in a month after germination, branches and leaves begin to carry bacteria. By the end of autumn, most of the branches and leaves of the new shoots were infected with bacteria in the same year, and the disease could be caused the next year when the conditions were suitable.

Prevention and treatment: spray at the tender tip stage to protect and prevent scab. Focus on the young fruit stage, spray every 15 days or so, 3-4 times in a row. Spray must be thoughtful and uniform, especially to fully spray fruit stalks, fruit branches and fruit mother branches, spray wet branches and leaves without dripping as the standard.

Medicament selection: difenoconazole, prochloraz, propionate zinc, etc.

3. Ulcer disease

The occurrence regularity: the optimum temperature was 25-30 ℃, and the peak period in spring was from late April to early May. Young trees, young trees are more susceptible to disease, high temperature and rain, leaf moths and other pests occur, the canker disease is serious.

Prevention and control methods: pay attention to prevention, medication frequently, do a good job of wiping and controlling tips, and release them uniformly. Results the trees could be sprayed once at 10 days, 30 days and 50 days after falling flowers, and the young trees and seedlings were sprayed once at 20-30 days after each shoot germination, and the phosphorus and potassium source pool was applied to promote the ripening of new shoots and reduce the damage cycle of leaf miner.

Medicament selection: copper preparations, thiazolyl zinc, mancozeb, pyrazole carbendazim, etc., pay attention to rotation, compound use. However, it is necessary to avoid copper preparation + copper preparation, so as to avoid superimposed drug damage.