What is rust on pear and how to treat it
Rust on pear is one of the most difficult diseases. From rust on pear leaves lose their ability to photosynthesis and become stained. And with a strong infection, the disease passes to the fruits and by the time of harvest there may not be a single healthy fetus.
Rust on pear and its treatment
Cause of disease
The disease received such an unusual name because of the color of the spots on the leaves and fruits. They are usually bright orange, yellow and pale red.
Rust is caused by a pathogenic fungus called Gymnosporangium sabinae.
In most cases, the fungus affects those varieties that grow in home gardens, because in order for the disease to occur, two plants are needed - a pear and a juniper. But the source of the disease is juniper, namely those varieties of it that are used to decorate houses outside and sites near them.
On these plants, the fungus develops, lives and forms spores that infect the tree. But the pear is only a stage in the development of the fungus. Then he again switches to juniper, infecting it, this completes the life cycle of the pest-fungus, but it can last up to 2 years. During this cycle, neither the pear nor the juniper can infect themselves.
Juniper has low resistance to frost and cold weather. Indeed, in late autumn, winter, and early spring, when the temperature drops below 0, the bark and branches of the plant are damaged - this provokes the appearance of a fungus.
The life cycle of the pest begins in the spring. After the first rain has passed, the spores come to life and wind flows can carry them up to a distance of 40 km. So the juniper variety can become a source of rust on the leaves of fruit trees.
Rust on pear leaves often appears in the spring, when the disease is still in the early stages of development.
The first signs of a pear disease such as rust can be seen during flowering. On the leaves, near their beginning and on the first fruits, small dark orange spots begin to appear. Already in July they become larger and turn pink with black dots inside.
If the infection is massive, then the rusty spots on the leaves of the garden pear spread to the whole tree, and sometimes to neighboring trees. After a strong exposure to the disease, the leaves may fall prematurely, and the first shoots do not grow and even dry out. After exposure to the disease, photosynthesis in the plant is disrupted, the tree does not receive enough nutrition, the fruits become smaller, and yield decreases.
There are resistant varieties to rust on pear:
- summer varieties: Chizhovskaya, Sugar, Ilyinka, Skorospelka;
- Autumn varieties: Berek Bosk, Borovinka red, Dekanka autumn;
- winter varieties: Belorussian late, Ligel Bere, Nika, Yakovlevskaya.
Most often, these varieties are planted in large gardens where fruits are grown for industrial use.
Some varieties are not treatable
There are unstable varieties that even timely treatment does not always help:
- Bere Ardanpon;
- Dikanka winter;
- Klapp's favorite.
But besides pears, the apple tree, quince, hawthorn can also become infected, and instead of juniper, thuja can become the focus of the disease. After exposure to rust, crop losses can be very large, sometimes more than 50% of the total harvest.
Ways to fight
To save a tree from a disease, you need to know what to treat and what to do. It is important that there is regular care: the formation of crowns, timely harvest, fertilizers and, of course, protection from diseases and pests.
But if after all the spots appeared, you need to look for methods of treating trees. The most common and effective means of control are chemical mixtures and solutions with mineral additives that can cure the plant or even save from imminent death. Here are some of them:
- processing pears from rust with a solution of Bordeaux liquid (3%). It is better to do this in the spring, during the period of budding, when the temperature reaches 5 °;
- spray the branches and trunk with an organic preparation with minerals before flowering begins;
- having bought a drug to enhance stability (Topaz fungicide), treat the crown when the trees have already faded and ovaries begin to form.
Processing trees from scab will be an additional means of combating rust. But when spots are found on the leaves, it is recommended to process fruit trees up to five to six times per season, with an interval of three to four weeks. You can also spray with a solution of colloidal sulfur or use a drug such as Topaz, which is widespread among gardeners and is very effective.
Rust control measures on pear are applied when infection has already manifested. In order for the pear to be more resistant to the disease, preventive measures must be observed. You need to think about this in the fall, when the time is approaching and the trees are becoming vulnerable.
The most reliable methods of prevention:
- do not grow juniper and thuja in garden plots, near fruit trees;
- equipping the site with special anti-wind systems so that fungal spores from wild-growing infected plants do not fly into the garden;
- if on the territory near the house coniferous plants already grow, it is necessary in the early spring to inspect them for the presence of fungus or the disease itself, and cut off the damaged areas;
- regular inspection of trees, pruning, fertilizing and processing protects against dangerous diseases: in the spring and autumn it is necessary to process juniper and other conifers with any preparation that contains copper;
- all infected leaves need to be burned at the end of autumn;
- To rejuvenate and improve the plant, you need to cut off the leaves covered by the disease, and branches up to 10 cm from the outbreak, and disinfect with a 5% solution of copper sulfate.
Now you know how to treat a young pear for rust. Keep track of all the trees in the garden, check for signs of illness so that the tree does not die.
Rust on pear is very dangerous and affects plants at an enviable rate. It is necessary to choose disease-resistant varieties and remember preventive measures and timeliness of treatment.