Seed Seedling raising technique of Longan

Longan, also known as round meat and longan meat, has the effect of tonifying heart, nourishing blood and calming the nerve. it is a well-known bulk medicine and food. Mainly produced in Fujian, Guangdong, Guangxi, Sichuan and Taiwan and other places. Seed propagation and grafting propagation can be used for its cultivation. Seed breeding techniques are introduced as follows: first, the selection of nursery land the nursery should choose a gentle slope or flat platform with good drainage, no stagnant water, irrigation in drought, slope of 5-10 °, deep, loose and fertile sandy loam (heavy clay should not be used as nursery land). After the nursery land is selected, it is necessary to plow and harrow ahead of time, remove stones and weeds, turn 25~30cm deeply, and the width of the border is 1-1.2m, which is about 20cm higher than the bottom of the ditch. After getting off the bed, travel according to the distance of 30cm on the border surface. 2. Apply sufficient basic fertilizer in order to cultivate robust longan seedlings, 3000~4000kg per mu, or high-quality farm fertilizer 4000~5000kg, calcium magnesium phosphate 100~150kg, lime 100~130kg are used to compost the fertilizer to ferment, rot and sprinkle evenly into the border ditch, and mix with the topsoil evenly before sowing. Third, the treatment of seeds Longan is peeled (eaten) to the pulp, if it is dried or dried in the sun, it will lose its germinating power. Therefore, the seeds used for raising seedlings should not be allowed to dry up. The seeds must be concentrated in time, mixed with fine sand, gently rub the pulp off the navel, rinse in water, remove inferior seeds, select fully ripe and full seeds, and germinate according to the proportion of 2 to 3 parts of fine sand (about 5% moisture) of one seed. You can also spread a layer of 10~15cm thick sand under the shade, then spread the seeds on the sand, cover it with a layer of sand (the sand exceeds the seed 1~1.5cm), and cover it with straw to prevent the water from evaporating and keep it moist to facilitate germination. When accelerating germination, the temperature should be controlled at about 25 ℃. If the temperature is too high, it should be drenched in cold water to prevent the seeds from losing their germinating power. After 3-5 days of sprouting, the seeds can be sown after the germ grows 1~2cm. 4. Sowing method the germinated seeds are sown in the row ditch where the row spacing is 30cm according to the 20cm. After covering the soil, the border surface is covered with wood bran or rice straw to prevent water evaporation, keep the soil moist and promote the rapid growth of seeds after germination. Generally, it is suitable to raise 800010000 seedlings per mu, and 6000000000 seedlings per mu is better. Too dense, not only affect the thickening of seedlings, but also affect the survival rate and growth of transplanting in the future, as well as the rapid expansion of the crown. When longan was sown, it was in the period of high temperature in early autumn, which was very disadvantageous to the growth of seedlings. According to the experience of Guangxi Land Reclamation system Farm, green manure such as pig dung beans and soybeans were sown between the rows of the border 45-60 days before sowing. By the time longan was sown, the green manure had grown about 20cm. The use of green manure to form a shady microclimate environment could prevent longan from being burned by the scorching sun at seedling stage and improve the survival rate. In this way, we can not build a shade, wait until the longan seedling leaves aging, the temperature dropped, and then pull out the green manure to cover the border. 5. Management of seedlings after longan seedlings grow 4-5 leaves and turn green, the root tip of the main root is cut off with a knife to promote the growth and development of lateral roots, and lay a foundation for improving the survival rate of transplantation and early fruiting in the future. When the leaves of longan seedlings are aging and sprouting again, we should pay attention to the management of fertilizer and water, apply fertilizer and water in time, promote the growth of longan seedlings and reach the grafting standard as soon as possible. In addition, there are many diseases and insect pests in longan, so we should pay attention to timely prevention and control. Longan seedlings are afraid of frost. Pay attention to frost prevention in the cold winter. When the seedling grows above 30cm, if it does not grow branches, it will be topped artificially to restrain its growth and height, and make the stem long and thick to facilitate grafting. More than 80% of the seedlings for the first anniversary reached the grafting standard (the stem diameter off the ground 10~15cm reached 1~1.2cm). The grafting could be carried out between August and September of the second year, and it could be out of the nursery in the spring or autumn of the third year.