Section 7 Guava cultivation techniques and pest control (2)

6. Seedling management The quality of seedlings is closely related to the level of management. In order to make the seedlings grow fast and reach the goal of early grafting, a 0.3% nitrogen solution can be sprayed once a month, but nitrogen can not be applied for a long time. It should be combined with compound fertilizer or compound fertilizer. When the seedlings are transplanted for 5-6 months, the seedlings can be as high as 30-40 cm and when the thickness is 0.4-0.6 cm, they can be grafted. 7. Grafting Research has shown that guava has the highest survival rate with intaglio buds and plants grow faster. Among the four methods of grafting, patch grafting, bud grafting, and cutting grafting, the survival rate of the budding grafting method is the highest, and the specific method for achieving 94.25% budding grafting is: Grab the scion when cutting buds, First cut a knife 0.8-1 cm above the shoot, 1.5 centimeters long, then cut obliquely at a 30-degree angle to the bottom of the first incision at the point 0.5-0.8 cm below the bud, remove the bud, cut the rootstock more than the bud Longer, after inserting the bud, note that the upper end of the bud must be exposed with a line of anvil cortex and finally tied. In addition, when guava is in severe growth season, it is not suitable for grafting. Grafting should be selected in late autumn. In the early spring, anion flow is less or less, and grafting survival is improved. Otherwise, excessive wound fluid will reduce graft survival rate. (B) rely on the method of raising seedlings (1) the mother plant's pre-falling pre-growing usually in the mother of the new shoots for the season scion, if the mother is too high, is bound to affect grafting. Before grafting, the mother plant was cut off, pulled and pressed, so that the mother plant had a large number of new shoots and the height of the hair transplant was 20-30 cm from the ground. (2) Selection and transplantation of rootstocks, selection of transplants, seedlings with diameters of 0.7 cm or more, seedlings as rootstocks, excavation from the nursery, hand squeezing the roots to make them beaded, and spurious on the fine mother trees beside. (3) Picking is good, just peeling, and the branches that have not been rounded are scions. Cut the skin opposite the rootstock and scion with a guillotine knife and tie the two layers together. After about 30 days, cut off the mother tree. (3) Cuttings and cuttings Cuttings are usually grown every year before sprouting in February. Choose robust 2-3 year old shoots, 1.2-1.5 cm thick stems, each 15 cm long, and the base is trimmed into a smooth triangular prism. , Insert 12cm x 15cm row spacing into the sand bed or obliquely into the sand bed, the depth is 1/2 of the length of the branch, then compact the soil, pour the water after the cuttings, and keep it moist, and grow new roots in 6-8 weeks. After 4-6 months, you can transplant or nutrition bag. For cuttings, if the shoots are treated with 2000 mg of 1 kg of indole butyric acid or rooting powder 123 for 3-5 minutes, the rooting effect will be better. India Prasad's 2500 mg/kg treatment with indole butyrate had a rooting rate of 98%, and the untreated control was 8.75%. Production uses full light spray, with leaf cuttings, and rapid cultivating strong seedlings. However, the root system of the cutting seedlings is less, and it tends to be biased to the side. The root system is shallower than the roots after 2-3 years of planting, and is susceptible to wind damage, and it is susceptible to root nematode disease. Therefore, planting cutting seedlings should choose sheltered areas, loose soil and good land. (4) The air pressure strips in the air, also known as coiled seedlings, are a common breeding method for guava. Generally selected 2-3 year old shoots with a diameter of 1.2-1.5 cm are ringed and peeled about 50 cm from the tip of the shoot, about 2 cm wide, and then coated with 200 mg/kg of indole or ABT. The rooted media mixed with decomposed bagasse or crushed cow dung can be sawed off from the mother tree after 50-60 days of new root intensive cultivation. The shoots are ready for planting after two new shoots are turned and green. No matter what kind of seedlings are grown, they must be bagged and concentratively implanted to ensure the quality of nursery stock. Most of the branches need to be cut off before planting, but do not cut them all in order to prevent the sprouts from sprouting too quickly, which will exacerbate the unbalance between the upper and lower parts of the ground. This will cause the shoots to â€œreturnâ€ and the seedlings to die. After prosthesis, appropriate shading, regulation of water, began to pour 1-2 times a day, after half a month can be reduced 2-3 days 1 water. After 1-1.5 months, it can be applied 2-3 times with diluted manure, and compound fertilizer can be added properly to facilitate the seedlings to grow robustly. Seedling nursery is the last part of nursery work. The quality of the nursery directly affects the quality of seedlings, the survival rate after planting, and the growth of young trees. Therefore, we must strictly abide by the nursery stock technical specifications to ensure the quality of seedlings. After the seedlings were transplanted, shading nets were removed in one month, and the nursery was released after one month of hardening. The diameter of the garden is required to be 1.0-1.2 cm or more, the height of the seedling is more than 40 cm, and the leaves are old and mature. China Agricultural Network Editor

Posted on June 13, 2018