What are the key points to note for rapid apple seedling propagation
Apple is one of the most common fruits in daily life, and it is also one of the fruit trees with the largest planting area in China. In cultivation, rapid seedling propagation techniques can quickly produce robust young plants, saving a great deal of time for production. However, there are several points to note in rapid seedling propagation. Let's take a look together below.
1. Choose fast-growing rootstock
Among apple grafting rootstocks, Malus prunifolia and Malus spectabilis are relatively cold-resistant, drought-resistant, waterlogging-tolerant, and salt-alkali-tolerant, and they have strong grafting compatibility with apple, well-developed root systems, and fast seedling growth. Generally, they can grow to grafting thickness by the summer of the same year. Choosing fast-growing rootstock is the foundation of rapid seedling propagation.
2. Grasp the seedling propagation time
Apple seedling propagation is best done by autumn sowing, when the climate is mild and favorable for seed germination. After sowing, mulch film should be applied immediately. For spring sowing, sowing should be done early to avoid young seedlings encountering high-temperature weather during growth, which is unfavorable for seedling growth. At the same time, cold protection and moisture retention measures should be taken. Common protection measures include cold-resistant wind barriers, sun-facing beds, hotbeds, and plastic film mulching. Use plastic film and greenhouse film to cover seedbeds for concentrated seedling propagation. Then transplant to the open-field grafting nursery. This method can advance the sowing period, but transplanting must wait until after the late frost.
3. Pinching and grafting
When the rootstock seedlings grow to 30 cm, pinch the tips to promote thicker stems. When the stem diameter reaches 0.5-0.6 cm, grafting can be done, and grafting must be completed before the end of June. Grafting generally adopts the high-position bud grafting method. After the seedlings survive, do not cut immediately. Instead, bend the rootstock 1-2 cm above the grafted bud without breaking it, to promote sprouting of the grafted bud. Wait until the grafted bud grows 5-6 true leaves before cutting the rootstock.
4. Strengthen fertilizer and water management
Choose loose and fertile plots as the nursery. At the same time, increase the application rate of base fertilizer. From seedling establishment to before grafting, apply 10-15 kg of urea per mu along with watering. After grafting survival, apply 8-10 kg of urea per mu; in August-September, apply 8-15 kg of compound fertilizer per mu each time, and spray foliar fertilizer once every half month. Spray 300 times urea solution in the early stage and 300 times potassium dihydrogen phosphate in the later stage.
The above is an introduction to the key points to note for rapid apple seedling propagation. We hope it can help you. To learn more related knowledge, please follow us.