A few notes on the cultivation of persimmon
Persimmon is an emerging seasonal fruit introduced from Japan. It can be eaten after ripening, sweet and crisp. Its natural astringent, off the edible, nutritious, crunchy, durable storage, long supply period and welcomed by growers and consumers. However, in the production of persimmons, there are strict environmental requirements, small fruit size, natural physiological fruit drop, and serious fruit drop before pests are cooked. In production, attention should be paid to preventing the occurrence of these phenomena, so as to promote the yield and quality of persimmon. And improve efficiency. According to the production experience, the following problems should be paid attention to in persimmon cultivation. 1, suitable planting. Sweet persimmon is a thermophilic tree species and can be cultivated in regions where the average annual temperature is above 10°C, and the temperature is required to be high. When cultivated in regions with an average temperature lower than 13°C, the fruit can not be naturally removed from the trees and become astringent. Astringent persimmons should therefore be planted in areas where the average annual temperature is above 13C. Generally speaking, persimmon can tolerate short-term temperature of -15-18°C, and below -18°C, it is susceptible to freezing. Therefore, it is recommended to choose the area where absolute low temperature is higher than -18°C to prevent freezing injury. 2, to promote fruit enlargement. To increase the fruit product rate. In the production of persimmons, there is a general phenomenon of small fruit, and the main reasons for the small fruit are: (1) Excessive results, excessive fruit retention, it is difficult to grow. (2) Poor site conditions, weak tree vigor, is not conducive to fruit expansion. (3) Lack of fertilizer and water, lack of nutrients, insufficient nutrient supply during the fruit growth period, and inhibition of the fruit's swelling and growth. (4) As a result of continuous fruiting for many years, the result was reduced in ability and it was unfavorable to produce large fruit. Therefore, in the production of targeted measures should be taken to facilitate the production of large fruit, improve the commercial character of persimmon. The main measures that should be adopted in production are: (1) When constructing a garden, choose a sandy soil or fertile soil with deep soil, fertile soil and strong water retention, and lay a solid foundation for the robust growth of persimmon trees. (2) Strengthen the methods such as cultivating loose soil, orchard and grass mulching, and planting green manure to create loose and fertile soil conditions, fertilize fertility, optimize the environmental conditions for the growth of persimmon trees, and follow the production path of strong roots and trees to ensure the robust growth of trees. Improve the capacity for solidification. (3) Strengthen fertilizer and water management. Should focus on the application of basal fertilizers and supplements of bulking fruit fertilizers in order to promote full expansion. Because the persimmon tree requires more pods, phosphorus and potassium are needed next, so the application amount of nitrogen fertilizer should be increased when persimmon trees are fertilized. Every year after harvesting fruit, the basal fertilizer should be applied in time, and 50-100 kg of high-quality farmyard fertilizer should be applied to 0.5 kg of urea, 1 kg of superphosphate and 1.5 kg of potassium sulfate to increase the nutrient reserve of the tree. 0.2 kg of diammonium phosphate and 0.5 kg of potassium sulfate were applied during fruit growth to promote fruit enlargement. There are watering conditions in the pre-germination pouring water, fruit expansion period depending on the soil moisture, to ensure adequate supply of fertilizer and water, promote the robust growth of trees to produce large fruit. (4) Control the output. Persimmon generally has many flowers and strong fruiting ability. If a large number of results are obtained, it is difficult to grow up. Therefore, after entering the fruit period, the branches should be divided according to the strength of the result, and the average tree branch should retain 1-2 fruit. Branches stay 2-3 fruit, all fruits and vegetables in weak branches in addition to fruit, to promote the rejuvenation of branching potential, persimmon trees due to physiological fruit drop phenomenon, fruit thinning should not be too early, generally should be after the physiological fruit drop fruit thinning is appropriate. (5) Maintain strong results. Persimmon fruit branch results tend to be thin after the branch, resulting in decreased ability to produce results, adverse production of large fruit, so in the production to strengthen the results of the renewal of the branch, the results of the short and weak branches should be retracted Zhuang branch after the decentralization For the apex pendulous branches should be properly retracted, raising the branches, to prevent weakness of the branches, short-term results of the mother branches to form a preliminary branch, in order to maintain the results of strong growth, improve the ability of results, and promote fruit full expansion. 3, to prevent falling flowers. Since most of the sweet persimmons only have female flowers and no male flowers, they are mainly parthenocarpy. In addition, rapid growth of new shoots during fruit set-up results in fruit and nutrient competition. As a result, fruit drop and fruit drop in the production of persimmon trees are more serious and have a great impact on production. Attention prevention. Comprehensive measures can be adopted to increase the fruit setting rate and increase the output. The main measures used in production are: (1) In the persimmon cultivation, it is best to use “Zengsi Pill†with male flowers as the pollination varieties, and take the road of bisexual and solid production in order to reduce the number of falling fruits and increase the yield. In general, the number of “zenji pills†should account for about 20% of the total number of cultivated plants. (2) Topdressing and watering before flowering to ensure material supply, 0.1% borax plus 0.3% during flowering. The gibberellin solution, or 0.1% borax solution spray, are beneficial to increase the fruit setting rate. (3) The growth of new shoots can be alleviated during the flowering period, and the shoots can be circumcised by spraying 100-150 times of 15% paclobutrazol or blooming at the new shoot speed from late April to early May each year to inhibit the production of new shoots. , Can effectively prevent falling flowers and improve fruit setting rate. 4, pests and diseases. Lead to serious fruit drop before harvest, and unfavorable production efficiency. The diseases and pests that cause more severe damage to persimmon are mainly schizandra, persimmon keratopathia, persimmon leaf spot disease, persimmon anthracnose, etc. Although their hazards are different, they will cause the fruit to fall off before it matures, resulting in reduced yield. Therefore, prevention and control should be done in production to reduce the occurrence of pre-harvest fruit drop. One year after the first generation of the schizandra, the mature larvae survived in the old skin of the persimmon tree branches, in the roots of the trees, and in the damaged dried fruits that remained on the trees. The first generation of larvae began to harm in late May. After the larvae hatched, the first larvae spun silky stalks, persimmons, and the body. They did not allow the persimmons to fall to the ground, and then bite the stalks into a ring and drilled into the fruit from the fruit shank. heart. The second generation of larvae in the late August in the Shidi under the harm of flesh, the fruit damage generally from green to yellow, red, soft, a lot of falling. Prevention and control should be strengthened when the artificial control, winter and spring should be carefully scraped off the old skin, in order to eliminate overwintering larvae. From June to early July, the diseased fruit should be cleared out of the park in time. The larvae can be burnt and destroyed in the tree body before the winter is over, reducing the insect source. Drug control should focus on the occurrence of adult emergence and larvae after hatching, can use 2.5% enemy killed 4000 times liquid spray protection. The keratoses were infected with hyphae on diseased leaf peduncles, and infested from June to July of the following year. In August, they were continuously infested, and in September a large number of deciduous fruits fell. Round spot disease occurs in immature ascosmic shells in diseased leaves and overwinters. Scattered ascospores in about June to July. Invasion through stomata. Occurrence of disease at the end of August and early September. Fruits turn red and soft after disease defoliation and flavor changes. Light and fall off quickly. Anthracnose pathogenic bacteria overwinter in new lesions, new conidia in early summer, initial infection, shoots beginning in early June, onset of fruit in early July in late July, severe onset in late July Falling fruit. Disease prevention and control: Before spraying, 5 parts of lime sulfur should be carefully sprayed before germination to kill the pathogenic bacteria on winter trees. This will lay a good foundation for prevention and control of the whole year. Spray protection should be started in late May, and protective fungicides should be used. Mancozeb predominates, and carbendazim and thiophanate-methyl should be used for the period from June to July to control and control hazards.