High grafting and replacement technique of olive

According to the investigation on the flowering and fruiting of several olive orchards, about 10% of the plants in which olive seedlings grow are male sterile trees and low-yield trees with a small amount of fruit.

There are two kinds of olives cultivated as fruit trees: olive (also known as white olive, mainly produced in Fujian) and black olive (mainly produced in Guangdong). As the offspring of olive seed breeding are prone to variation, and the fruit tends to become smaller, so rare and superior olive varieties are required to maintain their genetic stability through grafting (or high grafting replacement).

The tissue of olive xylem is loose and there is more tannin in tree sap. When the wound is exposed to air, the tannin in tree sap is easy to oxidize and coagulate, which affects the healing of grafting. Therefore, the survival rate of olive grafting (or high grafting) is low. In recent years, through several different transformation methods, such as planting after grafting of small seedlings, high grafting of young trees (2-3 years old) and height replacement of more than 5-year-old trees, we think that it is more feasible to replace species with high grafting of big trees by observing and analyzing the results of treatment.

The main results are as follows: 1. Rootstock selection and treatment, high-replacement planting plants mostly choose low-quality, low-yield and sterile trees, the tree age is generally more than 5 years old, the trunk is 2 meters away from the ground, the diameter is more than 0.1 meters, and the root growth is more developed. When high grafting, first saw off the upright trunk or main branches of the rootstock 1.5 meters above the ground or 0.5 meters above the branch point, and leave at least 1 Mel 2 auxiliary branches to ensure the balance of nutrition and water supply in the underground and aboveground parts of the tree.

2. It is better to choose the sunny day from mid-April to mid-May in the high pick-up period.

3. The high connection method adopts the embedding method.

(1) selection and treatment of scion selection of more than two-year-old strong branches in the middle and upper canopy, about as thick as the index finger to the middle finger (about 2mi 3cm in diameter). Cut off the leaves and upper twigs and wrap them with a clean wet cloth immediately. It is best to pick and pick the scion or use it the same day.

When cutting the scion, hold the top of the scion branch with one hand, on both sides of the base of the bud branch. Each cut a horseshoe-shaped oblique section with a length of about 5ml / 8cm, so that the incisions on both sides are wedge-shaped or obliquely triangular, and note that the incisions should be consistent with the rootstock incisions as far as possible. The upper end of the scion notch is at least 1 cm away from the bud, then cut 2 cm above the bud point in the upper part of the scion, and flatten the cut with a sharp knife. The length of scion is about 13m ~ 18cm, and there are 3 buds left in it.

(2) the cutting treatment of rootstock requires that the saw surface of the sawed rootstock should be horizontal or slightly inclined to the outside. At first, when the handsaw is less than the thickness of the cut planes on both sides of the scion, there are 4 saw wedge-shaped or oblique triangular incisions, and then the cut is flattened with a sharp knife, the cut scion can be quickly inserted so that the outer forming layer is aligned and closely matched. Then apply wax and tie the rope to fix it.

When cutting scions and rootstocks, the knife should be sharp, the action should be quick and accurate, and the incision should not be contaminated with dirt (such as finger sweat stains, dust, etc.) to avoid long-term exposure to the air, lest the oxidation of tannins in tree sap affect healing.

(3) after fixing and ensuring high grafting, wax moisturizing should be applied on the section of anvil, ear anastomosis and the top of scion, and be careful not to touch and shift. Wrap the wet grass rope from the cut of the rootstock to the saw surface to protect the scion. Then cover it with a cylindrical film (slightly larger than the rootstock), tie the lower end tightly under the grass rope, fill it with a clean, fine red heart with moderate humidity, cover the scion, leave about 20 cm space at the top, and keep the top moisturizing. Finally, wrap a layer of straw or Reed up and down the grafting joint to shade and cool down, and pay attention to at least 1 meter above the ground to avoid 0.2 cm, so as to reduce the sap flow at the joint of rootstocks and scions.

4. Management after high pick-up.

The management after high grafting of olive is very important to the success or failure of high grafting. The management mainly focuses on moisturizing and shading, timely breaking of membrane, rational use of auxiliary branches and so on.

The main results are as follows: (1) moisturizing and shading entered the high temperature season in summer and autumn soon after high grafting. In order to prevent the scion from losing water and drying caused by high temperature and strong sunlight and excessive ventilation, attention should be paid to peripheral grass shading and film sealing to promote scion healing and sprouting.

(2) the partially healed scion may sprout after timely breaking of the membrane and high grafting for about 30 seconds. At this time, do not rush to break the membrane and allow it to grow in the film. When the tip is about 10 cm long, a small hole is pierced at the top of the film, and there is a trace of air flow. Since then, the new tip is allowed to grow and even bend in the film, until the new tip is close to aging, to break the upper end of the film, so that it can resume upward growth. The outer grass quilt still needs to be encased and guaranteed. When overwintering, the new shoots of the scion should be closely covered with straw or Reed to prevent low temperature frost.