How to survive the winter safely in kiwifruit orchards? How to prevent frost damage? How should kiwifruit trees be remedied after frostbite?

Winter is an important period for kiwifruit to restore tree potential and save energy. It is necessary to strengthen the management of kiwifruit in winter to ensure that kiwifruit can survive the winter safely and lay a good foundation for a bumper harvest in the coming year. So how can kiwifruit orchards survive safely in winter? How to prevent frost damage? How should kiwifruit trees be remedied after frostbite?

I. performance of freezing injury of kiwifruit

The areas prone to frost injury are mainly distributed in river beaches, plots with poor air circulation, low-lying areas and Qinling river valley, and freezing damage occurs in other areas to varying degrees.

1. Generally, 1-2-year-old freshly grafted young trees are the most vulnerable to freezing injury. Xu Xiang and other over-growing kiwifruit varieties occur seriously, and the freezing damage of seedlings and orchards in full fruit stage is relatively mild.

two。 Most of the frozen parts are kiwifruit trunk frostbite, mainly within 50 cm upward of the rhizome, the frozen part shows the longitudinal cracking of the cortex, the frozen part has sap exudation, the epidermis looks intact, and the endodermis browns after scraping off. If the trees suffer from frostbite lightly, the severe ones will cause the trees to freeze to death, which will seriously affect the benefit of kiwifruit.

II. Preventive measures for Frost injury of Orchard in Winter

1. Increase the amount of warm fertilizer to improve the cold resistance of crop plants.

In winter, warm fertilizers such as phosphorus, potassium, boron fertilizer, plant ash, burning soil or soil manure and rotten pig manure can be applied appropriately to increase soil temperature, improve plant cold resistance, and spray 600-fold Wofeng foliar fertilizer. The application of solid soil regulator can improve the soil, promote the growth of plants and improve the cold resistance of crops.

two。 Do a good job in the protection of manor crop plants and improve the cold resistance in winter

(1) coverage. Before the severe cold, the dwarf kiwifruit can be protected by the whole plant with grass scaffolding, and the tall kiwifruit can be covered with waste plastic bags or covered with cold protection materials such as straw curtains to increase the temperature.

(2) bandaging the tree trunk. Before the severe cold, using straw or plastic film to bandage the main pole and main technology of kiwifruit trees can effectively prevent the occurrence of freezing injury.

(3) Irrigation before freezing: if the drought is serious in autumn and winter, it can be irrigated once before the severe cold, and if possible, it can be irrigated again before the cold air arrives, and the effect is better. Post-freezing irrigation: the leaves of crops lose a lot of water after freezing, so it is necessary to irrigate immediately to reduce the water loss of crop plants and die.

3. Take the way of smoking to dispel the cold spell and frost. Before the low temperature comes or on the night of the frost, weeds, husks, sawdust, dried branches and leaves or other smoking materials are stacked in the crop land for smoking, with a stack of 5 stacks per mu, burning tobacco at about 10:00 in the evening, and the smoking time is suitable for 6m / m for 10 hours.

4. Strengthen field management and do a good job in the prevention and control of diseases and pests. Timely ploughing and soil cultivation and the addition of microbial agents (soil fertility) can degrade into the best organic fertilizer for crops, make the soil loose and ventilated, clear the ditch and drain well, so as to facilitate the growth of the root system, enhance the tree potential and improve the disease resistance of the tree. Timely removal of frozen dead plants and yellow leaves, withered leaves, effectively do a good job in winter disease and pest control, so as to make crops grow healthily.

5. Disinfect with fungicides. For the management after fruit harvest, it is generally necessary to spray the leaves with fungicides, and it is recommended that Liangguoan 300 times spray. Replenish nutrients, repair wounds and promote healing. The trunk has wound, peeling, ulcer, need to use Kuiyuling brush to dry, as far as possible to expand the scope of more brushing, or high concentration spray, at the same time with Qingkuike, Wofengsu root irrigation effect is better.

6. Paint white to prevent frost. After falling leaves, the trees of the orchards that have been put on the shelves are painted white, mainly smearing the trunk and branches. The formula of whitening agent: 10 parts of water + 2 parts of quicklime + 1 part of stone-sulfur mixture + 0.5 parts of salt + a small amount of animal and vegetable oil.

III. Remedial measures after the occurrence of freezing injury

1. Strengthen the prevention and control of diseases and pests. After the occurrence of frost injury, the tree wound increases and the resistance decreases, which is most likely to aggravate the disease. In order to strengthen the prevention and control of kiwifruit diseases and insect pests dominated by bacterial canker, flank, schnaling, thiazuron copper, copper hydroxide and other agents can be used alternately and sprayed once at the end of pruning work. Spray 2-3 times at the initial stage of the disease (from the middle of February to the first and middle of March).

two。 If the bark is frozen and cracked, a breathable material can be used to bandage the wound before sprouting in spring to prevent water evaporation and miscellaneous bacteria infection to facilitate wound healing.

3. After the frozen fruit tree sprouts, pay attention to the root sprouting, for the frozen necrotic plants, the sprouting tillers at the base can be used to cultivate the new trunk after Lignification.

4. A few severely frozen fruit trees, the trunk cortex cracks seriously, and the cortex becomes brown and necrotic, so that nutrients can not be transferred to the root system, so it is necessary to bridge in time to ensure the supply of water and nutrients in the upper and lower parts of the tree.