A course on the latest management techniques of persimmon trees

Persimmon trees are widely distributed in our country, and they are planted in many places. Persimmon is delicious, juicy and nutritious, and is deeply loved by people. Persimmon has large roots, strong ability to absorb water and fertilizer, and convenient cultivation. When cultivating persimmon trees, it is necessary to do a good job in the maintenance and management of persimmon trees to make persimmon trees grow healthily.

Tree disk management

1. Turn the tree plate deeply, store water and preserve fertilizer: turn the tree plate twice a year, the first time from March to April in spring, and the second time after harvest to before freezing. Deep turning ranges from the trunk to the edge of the crown, slightly shallower near the trunk and deeper outward to prevent root damage.

2. Grass mulching on tree plate: grass mulching under tree plate is an effective way to improve soil nutrient and water status, and it is one of the important measures for high yield and high quality of persimmon. The first advantage is that it can slow down the rapid change of ground temperature under the tree plate and achieve the purpose of maintaining the stability of soil temperature; second, it can reduce evaporation and runoff and maintain the relative stability of soil moisture; third, it can increase the content of soil organic matter. The time of grass mulching is in March every year. Before covering the grass, apply appropriate amount of nitrogen and potash fertilizer, then water and then cover the grass. The appropriate thickness of the grass cover is 15mur20cm, the coverage is within the crown, but there is no grass within a radius of 30cm from the trunk. After covering the grass, sprinkle a little bit of earth and press the grass to prevent the wind and fire.

Application of base fertilizer in autumn

The suitable time for applying base fertilizer in autumn is from mid-late September to early October, when the soil temperature is high and the microbial activity is exuberant, and the decomposition and decay heat of organic matter is fast, which is beneficial to root absorption. Fertilizer is mainly organic fertilizer, and mixed with N, P, K and other available fertilizers. 100 kg of soil fertilizer, 20 kg of human feces and urine, 15 kg of plant ash, 0.5 kg of urea and 4 kg of superphosphate were applied to each plant.

Using strip ditch or annular ditch, dig a 50 cm wide and 60 cm deep trench or annular ditch along the outer edge of the crown, put topsoil and immature crop straw into the bottom of the ditch, mix the mature soil fertilizer and fine fertilizer into the 20ml-30cm soil layer. No matter which way to apply fertilizer, rotten farm manure and fine fertilizer should not be applied too deep, so as not to affect the fertilizer efficiency.

Skillfully applying topdressing

Persimmon trees are fertilized twice a year. For the first time, the whole tree was covered with grass in March in spring. The second time was in the period of rapid fruit expansion in late July. Topdressing was dominated by available fertilizer, nitrogen fertilizer in the early stage and potash fertilizer in the later stage. And mixed with appropriate amount of phosphate fertilizer. Those who have irrigation conditions can top fertilizer on time, and those without irrigation conditions can topdressing according to the weather while rain. Generally, according to the size of the crown, each plant digs a number of small holes, which can be filled with soil after applying chemical fertilizer.

The amount of topdressing should be determined according to the crown size and load. Generally, mature trees apply 0.5 kg of nitrogen fertilizer, 0.5 kg of potassium fertilizer and 0.75 kg of phosphate fertilizer. In the growing season, 0.5% urea, 200 times potassium dihydrogen phosphate or photosynthetic micro-fertilizer were sprayed with foliar fertilizer for 3 times for 4 times.

Reasonable pruning

In production, persimmon trees are often neglected to prune and let them grow naturally, resulting in weak upper and lower strength, poor light, bald inner chamber, outward movement of fruit parts and reduced yield. In pruning, we should master the principle of cutting less, retreating quickly after the result, and not more branches.

The main results are as follows: 1. Light shearing is the main trimming in winter, which should be combined with sparse and shrink, adjust the skeleton and improve the ventilation and light transmission conditions. It is necessary to remove some over-dense branches, thin and weak branches, overlapping crossed branches, dry and withered branches of diseases and insects, and pay attention to retreating perennial weak branches to stimulate the formation of new branches. Cut short branchlets to promote secondary buds to sprout into branches.

2. In summer pruning, we should master the principle of the combination of thinning, picking, sprouting and ring cutting, that is, to remove the big branches and the new shoots whose inner chamber is too dense, weak and improperly positioned, and the branches left behind are easy to blossom and bear fruit due to the improvement of light and nutritional conditions. Before sprouting, the annual strong branches are carved into buds, medium and short branches are promoted, and the new shoots and other branches from the sprouts are coring at 30ml and 40cm. After the weak branches are coring, the top is easy to form flower buds, and after the strong branches are coring, the secondary branches can form flower buds in the same year and bear fruit the next year. In order to improve the fruit setting rate, the large auxiliary branches should be cut around at the flowering stage.

3. In autumn, the best time to pull branches in a year is September, but in the summer season from May to June, the upright branches can be pulled at any time, and the vigorous shoots can be taken. The main objects of drawing branches in September are the main branches and auxiliary branches. The opening angle of the basic main branches should be about 90 °, less than 70 °downward, more than 70 °upward, and inappropriate azimuth to the left or right. Note that this kind of big branch is not hard to pull, it is easy to split, the correct way is to saw 3 times behind, then pedal the base with your feet, pull both hands down slowly, and finally fix it, leveling all the upper main branches and side branches.

Control of diseases and insect pests

The main pests of persimmon are shell worm, persimmon stem worm, persimmon caterpillar and so on. The main diseases are angular spot and round spot, comprehensive control measures:

1. In early winter, thoroughly clean the orchard, remove the persimmon stalks on the residual trees, and clean the fallen leaves, diseases, pests and branches around the persimmon trees, so as to remove the overwintering places of diseases and pests such as round spot, corner spot and persimmon stalk moth, and reduce the harm in the coming year.

2. In winter, the old thick warped skin on the trunk and big branch is scraped and destroyed, and the trunk is painted white after scraping, which can eliminate persimmon stalk worm and grass paramecium.

3. Chemical control, persimmon trees should be carefully sprayed with 5 Baomedu stone sulfur mixture before germination, and alternately spraying multi-dose Bordeaux solution, mancozeb and methyl topiramate from early June to early August for disease control, and according to the occurrence of insect pests, timely spraying control.