transplant
definition
Grafting is one of the artificial vegetative propagation methods of plants. That is, the branches or buds of one plant are grafted to the stems or roots of another plant, so that the two parts connected together grow into a complete plant.
Related definition
Grafted branches or buds are called scions, and grafted plants are called rootstocks or scions. Scions usually choose seedlings with 2 ~ 4 buds, which become the upper part or top of the plant after grafting; Rootstock becomes the root part of the plant after grafting.
principle
Grafting by using the function of injured callus of plants. When grafting, the cambium of the two injured surfaces are close together and tied together. As a result, due to cell proliferation, they heal each other and become a whole connected with vascular tissue.
influencing factor
The main factor affecting the survival of grafting is the compatibility between scion and rootstock, followed by grafting technology and post-grafting management. The so-called affinity refers to the ability of scion and rootstock to be identical or similar to each other in internal organizational structure, physiology and heredity, so as to be able to combine with each other. High affinity and high grafting survival rate. On the contrary, the survival rate is low. Generally speaking, the closer the genetic relationship between plants, the stronger the affinity. For example, apples are grafted on sand fruits; Pear is connected with Li Du pear and Qiuzi pear; Persimmon grafted with black dates; Walnut and Juglans mandshurica have good affinity.
meaning
Grafting is of great significance to the propagation of some seedless fruit trees (such as some varieties of persimmon). Grafting can not only maintain the excellent characteristics of scion varieties, but also make use of the favorable characteristics of rootstock to achieve early fruiting, enhance the ability of cold resistance, drought resistance and pest resistance, and also make economic use of propagation materials to increase the number of seedlings. Commonly used for the reproduction of fruit trees, trees and flowers; It is also used for seedling raising of melons and vegetables. Grafting, branch grafting and bud grafting can be divided into two categories. The former is suitable for spring and autumn, especially in spring. The latter should be carried out in summer.
function
1. Enhance plant disease resistance. Cucumber grafted with black-seeded pumpkin can effectively control cucumber wilt. At the same time, it can also delay the occurrence of downy mildew; After grafting eggplant with CRP and tomato as rootstocks, the occurrence of cucumber can be basically controlled.
2. Improve the low temperature tolerance of plants. Because the rootstock has developed root system and strong stress resistance, the grafted seedlings are obviously resistant to low temperature. For example, the cucumber grafted with black-seeded pumpkin has a good root elongation at low temperature, and the root system can still grow normally at ground temperature 12- 15℃ and air temperature 6- 10℃.
3. It is beneficial to overcome the harm of continuous cropping. Cucumber root system is fragile, so continuous cropping is prohibited. Cultivation in solar greenhouse is easily affected by soil salt accumulation and harmful substances. After switching to black seed pumpkin root, the harm of soil salt accumulation and harmful substances can be greatly reduced.
4. Expand the scope and capacity of root absorption. After grafting, the root system of plants grows exponentially than that of self-rooted seedlings, absorbing about 30% more nitrogen and potassium and more than 80% more phosphorus than that of self-rooted seedlings in the same area, and can make use of phosphorus in deep soil.
5. It is beneficial to increase the output. Grafted seedlings with large stems and leaves can increase yield by more than 40%. Using late-maturing varieties as rootstocks and early-maturing varieties as scions not only retains the early maturity, but also greatly prolongs the fruiting period and improves the total yield.
place
Grafting is best done in a greenhouse. In high temperature season, shading nets or grass curtains should be used to shade seedlings to avoid excessive wilting of seedlings and affect their survival. For example, grafting eggplant at the end of winter in August is in the high temperature period, and heatstroke prevention is the key. In the low temperature season (such as the grafting of cucumber and cucurbitaceae in late September+10/early October, 65438), heat preservation is the main factor, and low temperature is not conducive to wound healing. The suitable temperature for grafting should be 25-28℃, and the relative humidity of air should be above 80%. When the humidity is not enough, use a sprayer to spray water into the air or wall to increase the humidity.
device
1. Blade: a double-sided blade for general shaving. When grafting, it is broken in half, which not only saves the blade, but also facilitates the operation.
2. Bamboo stick: one is used to insert a jack on the rootstock, the thickness is the same as that of the young stem of the scion seedling, and one end is cut into a wedge shape. The other one is not strict in thickness, and one end is cut into a single wedge, which is used to pick out the growing point of pumpkin when docking.
3. Grafting clamp: used to fix scion and rootstock. At present, there are two kinds of grafting clips on the market, one is eggplant grafting clip and the other is melon grafting clip.
The old grafting clip should be soaked in 200 times aldehyde solution for 8 hours in advance for disinfection. The operator's fingers, blades and bamboo sticks should be smeared with 75% alcohol (medical alcohol) and disinfected every 1-2 hours to prevent the wound from being infected by miscellaneous bacteria. But the leaves and bamboo sticks wiped with alcohol cotton balls must wait until they are dry, otherwise the survival rate will be seriously affected.
way
1. Docking mode: the operation method is the same as that of pumpkin docking.
2. Splitting method: removing the growing point and the heart leaf from the rootstock, and vertically cutting a gap of 8- 10 mm between the two cotyledons; Cut the scion about 1㎝ under the cotyledon into 8- 10 mm double wedges on both sides of the young stem with a blade, and gently insert the double wedges of the scion into the interface of the quasi-rootstock, so that the two cuts are closely attached, and fix the grafting clip.
3. Insertion method: firstly, remove the true leaves and growth points of gourd seedlings with bamboo sticks, and insert the bamboo sticks downward from the growth points between the cotyledons of rootstocks. 5-0。 7㎝ deep, and then cut the watermelon seedlings below the cotyledon 1㎝ into about 0 with a blade. 5㎝ Wedge, while pulling out the bamboo stick, insert the watermelon seedlings, which is the direct insertion method. Another inserting method is oblique inserting method, in which a single-sided wedge-shaped bamboo stick with the same thickness as the scion is used, and the plane of the bamboo stick is obliquely inserted downward from the cotyledon base of one side of the gourd seedling to the other side, and the tip of the bamboo stick is pushed to or pierced through the epidermis of the young stem, and then cut into oblique stubble under the cotyledon of the watermelon seedling 1㎝, and when the bamboo stick is pulled out, the oblique stubble of the young stem of the watermelon seedling is quickly inserted downward. After the connection, move into the shed to strengthen management.
First, rootstock seedling raising and nursery management?
1? Seeding and seedling raising: firstly, the selection and arrangement of seedling raising sites. Apricot trees have strong adaptability and low requirements for soil conditions. You can choose land with deep soil layer, loose soil and general fertility. First of all, the sowing place is plowed deeply with a mountain plow, raked thinly, and sown with a plow. The row spacing is about 30cm, and the sowing depth is generally 10- 15cm. About 25-40 kilograms of seeds are used per mu, and wide and narrow rows are used for sowing, that is, one blank row is left every two rows, which is convenient for field management and grafting. Seeds should be selected when they are fully mature and full. If the seeds are obsolete, clean the chaff and moldy seeds with clear water before sowing, and increase the sowing amount appropriately. The sowing time is good before the land freezes in autumn and winter, and the seedlings emerge neatly in the second year, and the seeds do not need sand storage treatment, which is simple and easy to implement.
2? Nursery management: after seedling emergence in early spring, when the seedling height is about 15-20 cm, applying a small amount of urea in combination with weeding and loosening soil can accelerate seedling growth. You can use water if you can, and the effect is better. Topdressing on dry land is best carried out when the water content is good after rain. At the seedling stage, the seedling field is also prone to rodent damage, which often causes the cotyledons of the seedlings to be scratched and the stems of the seedlings to be bitten off. It is necessary to prevent and control rodents in time. When the height of seedlings is more than 30cm, light heading can be used to facilitate the coarse growth of seedlings. In late June, when the root diameter of the seedlings reaches 0.6-0.8 cm, the seedlings can be grafted. ?
Second, grafting?
T-bud grafting (which people call hot sticking skin) is the best and easy to operate. The survival rate is as high as 90%, and it can be grafted in June-September. The specific operation method is as follows:
1? Tools and materials?
(1) Grafting knife: it can be made by yourself: select an old hacksaw (about 12cm), grind it roughly on the grinding wheel, smooth the toothed side, and cut the front end into a round belly shape, about 2. ? 5-3 cm, slightly grinding off a part of the back of the tip to make it sharp, and then grinding the tip with a fine grinding stone. The handle is covered with a plastic tube with appropriate thickness, and thin bamboo and wood pieces are tightly inserted on both sides. Hold the length of the handle in your hand and don't show your tail. In this way, the grafting of rootstock seedlings can be flexibly rotated and unimpeded. ?
(2) Banding: Select plastic sheets with appropriate thickness and strong elasticity (which can gradually shrink and recover after stretching), roll them into more than ten layers like egg rolls, and cut them into strips with a width of 0.6- 1 cm. After cutting, every 100 or 50 strips are bundled, and then cut into small pieces of about 10cm, and bundled into small bundles for later use. ?
(3) Other articles: wet cloth, which is used to cover scions that are transported and stored for a short time. Can bottles, one bottle for each person, with half a bottle of clear water. When grafting, scions can be stored, which can be taken as needed without losing water. In addition, we should also prepare labor insurance supplies such as straw hats, cushions and heatstroke prevention drugs.
2? Scion collection and preservation?
(1) scion collection: scions with pure varieties, strong growth, bright colors and no pests and diseases should be selected. And then collect according to that thickness of the rootstock. But if the bud is too big and the base grows and deforms, it is not suitable. The best collection time is early morning, when the temperature is low, the evaporation of water is small, and the seedlings are full of water and moist. When cutting the ear, the incision should be smooth and don't tear the ear skin. Remove the shoots and leaves of the scion, leaving only the petiole 0.8- 1.0 cm long, and then wrap it with wet cloth. Avoid strangulation and wear when binding and transporting.
(2) scion preservation: the harvested scion should be preserved in a cold storage or a cool and humid fruit cellar. Here are some simple and effective storage methods.
(1) Put the bundled scion with the tip facing upwards into the woven bag, tie the bag mouth tightly and hang it in the well. First, soak the base of the scion in water, and then lift it out of the water, which can be preserved for about a week.
(2) Dig a hole 30cm deep in the shade, the length and width of which shall be subject to the scion can be put in, bury it with wet soil, and cover it with weeds and other shade objects, which can also be preserved for more than a week;
(3) When there are few scions, the washbasin can hold half a basin of clean water. Immerse the base of the scion in the water and store it in a cool soil hole. Change the water every 1-2 days, and it can be stored for several days. ?
3? Grafting?
(1) Bud grafting: Select a complete fresh bud in the middle of the scion, cut it from the top of the bud 0.5cm (less than half a circle around the scion when cutting) to the xylem, then gradually deepen it from the upper part of the bud at an angle of about 0.8cm, and cut it to the cutting edge of the upper part of the bud (don't hold it too hard to avoid scratching other buds). Gently pinch both sides of the bud with your thumb and forefinger and slowly break off the bud skin. Don't pinch the bud. The bud is shield-shaped, about 1.2- 1.5 cm long, 0. 5-0.6 cm wide. Two small white spots can be clearly seen on the inside of the bud piece, the lower part is the attachment point of the petiole and the upper part is the bud growth point. Any bud growing point that turns black, brown, yellow or falls off and scratches should be discarded.
(2) Rootstock: select a rootstock 5- 10 cm above the ground, and cut a knife (the blade rolls for less than half a turn) at the place with smooth surface without hurting xylem. Then cut down from the transverse incision, the length is 1.5cm (slightly longer than the budding), and the depth is the same as that of the transverse incision, making it T-shaped. Then twist the knife left and right along the longitudinal incision to pry open the cortex. ?
(3) Grafting: While prying open the cortex with a knife, hold the petiole of the bud grafting with your left hand, gently press the rootstock down to tilt, and prying open with a knife to insert the bud grafting. Don't rub on the rootstock when inserting buds to protect the growing point. The upper plane of the bud connection is closely matched with the upper plane of the T-shaped opening of the rootstock. ? (4) Binding: binding with plastic strips after grafting. The first requirement is to tie it tightly, so that the bud grafting and rhizome are closely combined without leaving any gap. Secondly, the T-shaped incision should be tightly wrapped and not exposed, which can not only prevent water evaporation, but also prevent pests from laying eggs in the wound, and the larvae will eat holes after hatching, leading to the death of the bud. Third, rapid grafting is the key to survival. The exposure time of bud grafting should be minimized, and the operation technology should be skilled to improve the grafting speed. When tying a knot, hold one end of the belt with your left hand and the other end with your right hand, and wind it down from the upper end of the T-shaped mouth for two or three times, wrap the lower incision, then screw it up to make the upper and lower layers cross, and then cross and tighten the two ends of the belt upward to tie a knot. The advantage of this method is that it can prevent rotten buds from being soaked in rain, and it can also cooperate with the anvil to cut off the knots of the binding belt without special unbinding, saving time and labor. Generally, before germination in March of the following year, the rootstock tip is cut off at 65438±0cm above the bud. It is also useful to apply plant growth agents such as high-efficiency zhizhibao on grafted buds. That year, in order to promote growth and speed up seedling raising, roots were cut off and branches were removed. ?
Third, on-site management?
1? Removing sprouting: In order to ensure the rapid sprouting and growth of grafted buds after rootstock cutting, the clustered sprouting can be removed for 2-3 times in April. When operating, it is necessary to prevent damage and tearing of bark. ?
2? Pest control: During spring and summer, especially in the germination stage, it is necessary to prevent scarabs from biting leaves. In summer and autumn, omethoate, phoxim, malathion, pyrethroid and other drugs can be sprayed to control aphids, leaf rollers and other pests. ?
3? Weeding and fertilization: Weeding more than 3 times a year. Cooperate with weeding and apply nitrogen fertilizer such as urea and ammonium bicarbonate. It can be furrowed and applied, and at the same time, an appropriate amount of phosphorus and potassium fertilizer can be applied, 5-7 kg per mu. Where conditions permit, irrigation can be done once when the drought is serious. ? In addition, we must do a good job in preventing people and animals from being trampled and damaged.