Breeding seedlings should pay attention to several technical aspects
September 03 12:32:09, 2025
To effectively understand and utilize the different biological traits of seedlings, it's essential to combine their characteristics with practical application. Through methods such as seedling testing, clone comparison forest trials, and regional adaptation tests, we can ensure that species are not introduced blindly. For instance, in ecological engineering projects, species like *Populus × euramericana* (107 Poplar) from Europe and the U.S. are favored for their strong drought and cold resistance, surviving even in temperatures as low as -30°C. Another example is *Malus argentea*, a nationally protected species, which thrives in acidic soils and has a long lifespan with resistance to sulfur dioxide, making it an ideal choice for urban and industrial afforestation. Therefore, breeding in accordance with the specific characteristics of each seedling variety is crucial for improving survival rates and capturing market opportunities.
Choosing the right nursery site is equally important. The selected land should be convenient, with fertile, loose soil and a pH between 7.0 and 8.0, while maintaining at least 3% organic matter. The quality of the nursery significantly affects seedling growth, yet it's often overlooked. Common issues include poor site selection, where the location doesn't meet the water, heat, nutrient, and gas requirements for healthy growth, leading to stunted seedlings or weak emergence. Even increased fertilization may fail to produce desired results. Additionally, neglecting soil improvement leads to structural changes and reduced nutrients, which negatively impact seedling development. In large-scale cultivation, soil compaction and degradation can occur, affecting root growth and increasing the risk of root nematode diseases.
Rational fertilization is also key. Fertilizer application should be based on soil properties, with a balanced use of nitrogen, phosphorus, potassium, and organic matter. This approach not only saves labor but also improves fertilizer efficiency, reduces nitrogen leaching, and enhances soil organic content. Typically, 60% of the total fertilizer should be applied as base fertilizer, while 40% is used as top dressing during the seedling stage. Top dressing should follow the principle of "fertilize where there is need, and avoid where there isn't," ensuring efficient nutrient uptake.
When using seeds or seed strips for sexual reproduction, netting before sowing is essential. Seeds collected from mother trees often contain impurities, so sieving and rinsing with water is necessary. Disinfection using chemicals or lime water helps prevent disease. Germination should be done in a greenhouse to ensure optimal conditions. For vegetative propagation, cuttings must be stored properly. They should be sorted by size and stored by digging to a depth of 50–70 cm, with the roots facing upward. During storage, the polarity should be reversed to promote root formation and callus development, depending on the seedling’s needs.
Timely irrigation is critical. Watering should be done at the right time, avoiding the small-water-pouring method. There are five key times to irrigate: first, watering before sowing to check soil moisture; second, watering after transplanting to maintain soil moisture and increase ground temperature; third, watering after top-dressing to prevent fertilizer burn and aid absorption; fourth, watering after the seedling head develops to enhance trunk diameter and delay defoliation; and fifth, watering after dormancy to protect the root system and prevent frost damage. Proper irrigation ensures healthy growth and long-term survival.