The Latest Cutting Propagation Techniques and Methods for Red Tip Photinia: A Tutorial
In production, red tip photinia is mainly propagated by cuttings. Cutting propagation has the characteristics of low cost, simple operation, and a high survival rate. It is a propagation technique that can be carried out in ordinary plastic greenhouses, making it suitable for promotion and application in most tree nurseries. Let us take a look below at the cutting propagation technique for red tip photinia!
Cutting Preparation for Red Tip Photinia
Choose a field with good drainage, where the field dries after rain, with a relatively low groundwater table, convenient transportation, and a stable water source to build the nursery. For cutting in a single-span greenhouse, cover it with greenhouse film and add a shade net. After leveling the ground inside the greenhouse, build a ground-level cutting seedbed, which can be about 100 cm wide. Install 10-12 cm high retaining boards around it, and spread a layer of fine sand at the bottom to facilitate drainage. The cutting substrate can be vermiculite plus peat, or clean yellow subsoil plus fine sand. The seedbed and substrate must be disinfected with fungicides and insecticides to prevent pests and diseases.
Cutting Methods for Red Tip Photinia
1. Cutting time: The requirements for cutting time for red tip photinia vary by region. In the middle and lower reaches of the Yangtze River, spring, summer, and autumn are best. Generally, temperatures between 15-35 degrees are acceptable, with 20-30 degrees being most suitable. Therefore, late April to late June and late August to mid-October are the golden seasons for cutting red tip photinia.
2. Selection of cuttings: Select thick, robust, semi-lignified one-year-old branches as cuttings. Cut the cuttings to a length of 3-5 cm, with flat cuts at both the top and bottom. During the golden cutting season, because the temperature is suitable, generally retain half a leaf. Based on experience, retaining a little less than half for large leaves and a little more than half for small leaves is more appropriate. Pay attention to keeping the cuttings moist, shading them, and sprinkling water. When cutting the cuttings, it is best to use special scissors, which make smaller wounds than ordinary flat-edged scissors. The cut end of the cutting has the phloem facing inward and the xylem slightly concave toward the center, making it easy for the cutting to form callus tissue and roots, with a high survival rate. It is best to take cuttings and insert them on cloudy days and before 10 a.m. and after 4 p.m.
3. Cutting method: Using rooting agents on red tip photinia cuttings can shorten the rooting time from 40 days to 7-15 days. Therefore, before cutting, the cuttings should first be treated for rooting. Commonly used rooting agents include finished products such as ABT and Guoguang, and biochemical raw materials such as naphthaleneacetic acid and indolebutyric acid. Before cutting, water the seedbed thoroughly. The cuttings should not be inserted too deep into the soil, generally 2/3 of the cutting. Use 400-700 plants per sq m. The leaves at the top of the cuttings should face the same direction so that they receive uniform light, which helps them root early and sprout early. After inserting, water thoroughly again. After the moisture on the leaves dries, spray with thiophanate-methyl or chlorothalonil at 600-800 times dilution to prevent disease. Finally, cover the entire seedbed tightly with a small arch film.
Post-Cutting Management for Red Tip Photinia
1. Shading and topdressing: From cutting until rooting and sprouting, shading is required, maintaining a shading rate above 75%. After cutting, foliar topdressing should be carried out frequently, and it can be done together with spraying for disease prevention. From callus formation to the emergence of young roots, spraying a nitrogen fertilizer solution at a concentration of 50×10-6 is sufficient. After the root system has formed in large numbers and before transplanting, the nitrogen fertilizer concentration can be increased to 100×10-6 to 150×10-6.
2. Pest and disease prevention: After cutting, pest and disease control should be strengthened. Immediately after cutting, spray carbendazim and thiophanate-methyl at 800 times dilution, and thereafter spray once every 5-7 days. After rain, fungicides must be sprayed promptly. During the cutting period, anthracnose is mainly likely to occur, requiring periodic control. The main control agents include anthracnose Fumei, mancozeb, and chlorothalonil. The main pests include aphids and moth larvae, and the main control agents include imidacloprid and beta-cypermethrin.
3. Strengthen management: After 15 days, some cuttings begin to root, and the substrate moisture content should be appropriately reduced, generally maintained at about 40%. When more than 50% of the cuttings begin to root, the film can be gradually opened for ventilation, and shading can be reduced to about 50%. When all cuttings have rooted and more than 50% have leafed out, gradually remove the greenhouse shade net and film, provide relatively sufficient light, and begin hardening the seedlings.
4. Hardening and potting: For potting rooted seedlings, use a medium of 80% peat + 20% perlite. Generally, lime is added to peat to adjust the pH value while supplementing calcium. When potting seedlings, generally lift, plant, and water immediately. Seedlings are prone to frost damage at the young stage, so small seedlings are best overwintered in a greenhouse, or reduce water supply and do not fertilize. In summer high temperatures, it is best to spend the summer in a shade shed. For water management, pay attention to watering when dry and withholding when wet. For fertilizer management, generally mix 4 kg of controlled-release fertilizer per cubic meter of medium at potting, and after potting regularly apply a nitrogen water-soluble fertilizer at 700-1000 times dilution.