Detailed Explanation of Lilium dauricum Propagation Methods, Easily Master Seedling Techniques

(1) Growth, Development and Habitat of Lilium dauricum

Lilium dauricum is a plant that germinates relatively early. In the cold Heilongjiang Province, seedlings break through the soil and germinate in late April when the soil has just thawed. The most suitable growing environment for Lilium dauricum is roadsides, forest gaps, meadows and other places with good soil and moisture conditions and sufficient light. Investigations and experiments have proven that when the light intensity is 50% to 100%, Lilium dauricum grows best, with sturdy plants reaching 80 to 130 cm in height, producing 1 to 12 flowers per year, full fruits, large underground bulbs, and up to 6 small bulbs formed at the base. When the relative light is about 25%, Lilium dauricum becomes slender and weak, relatively short, with only 1 to 2 flowers per plant; although it can bear fruit, at most 1 fruit is produced, and it is not full, with small seeds and small underground bulbs, and the plant begins to wither in August. When the relative light is only about 10%, Lilium dauricum plants are short and small, cannot flower or produce only one flower, do not set seed, have small underground bulbs, and the above-ground parts gradually wither in mid-July. Lilium dauricum is suitable for growing in soil with a moisture content of 30%-40%. When the soil moisture content is below 20%, the plants are prone to withering or death.

(2) Propagation Methods of Lilium dauricum Lilium dauricum growing in nature mainly reproduces sexually by seeds and asexually by bulbs.

1. Seed Propagation Method The seed germination of Lilium dauricum belongs to the hypogeal cotyledon type, with difficult germination and great variation in the length of the germination process. In nature, after seeds are dispersed, very few can germinate in the same year and grow vegetative leaves the following spring. Most seeds germinate the following spring, grow small bulbs, and after a brief dormancy, grow vegetative leaves in summer or autumn; or after summer (or autumn) dormancy, followed by vernalization through the cold winter, they can only germinate vegetative leaves in the second spring. The great variation in the germination process of Lilium dauricum shows that the heterogeneity of Lilium dauricum seeds is particularly strong, which is beneficial for the continuation of the population. After seeds are dispersed, under various environmental conditions, the two forms of early germination and delayed germination can coexist for a long time, thereby avoiding catastrophic destructive damage. When artificially sowing, the temperature range for Lilium dauricum seed germination is 10 to 30°C, with the optimum temperature being 20°C. At 20°C, seeds begin to germinate in 7 to 10 days, the germination rate can reach over 60% in 30 days, and over 85% in 50 days. As the temperature decreases or increases, the seed germination rate declines. If the temperature is too high, seeds are prone to molding; if too low, they enter a dormant state. Lilium dauricum seed germination begins with the elongation of the hypocotyl; after 4 to 7 days, the front end of the hypocotyl gradually swells to form a small bulb, and then vegetative leaves (true leaves) germinate from the bulb. Vegetative leaf germination is slow, requiring 10 days under suitable conditions; if conditions are unsuitable, the small bulb may never germinate vegetative leaves and remain in a "dormant state." To break the dormancy of small bulbs, the seedling small bulbs can be treated at a low temperature of 2 to 5°C for 1 month, which enables over 95% of small bulbs to germinate vegetative leaves within 12 days after the low-temperature treatment is removed. In addition, the germination rate of seeds sown at a constant temperature of 25°C (50 days) is about 60%; although lower than at 20°C, when sown for about one month, 20% to 30% of small bulbs can directly germinate vegetative leaves. Therefore, when artificially sowing, as long as the two temperatures of 20°C and 25°C are controlled in a timely manner and the soil moisture content is maintained at 30% to 40%, a certain number of Lilium dauricum seedlings with vegetative leaves (true leaves) can be obtained in about 1 month.

2. Asexual Propagation Method Asexual propagation of Lilium dauricum is mainly carried out by bulbs. In nature, the multiplication of Lilium dauricum bulbs often occurs in the following ways.

1) Up to 4 to 5 small bulbs can develop within the mother bulb.

2) Small bulbs can form on a section of stem node buried in the soil, usually 3 to 4.

3) The scales on Lilium dauricum bulbs have nodes and are loosely attached, making them very easy to be knocked apart by soil insects and the like. The separated scales differentiate meristematic tissue at the break at the base of the node and rapidly form small bulbs; each scale node generally produces only one small bulb.

4) The basal roots emerging from the bottom of Lilium dauricum bulbs can, in rare cases, grow creepingly, and on the creeping roots, 1 bulb can form at intervals of 0.5 to 1 m.

Artificial asexual propagation is mainly carried out by scale cutting. The simplest method is to use a plastic bag filled with sand or leaf mold with a moisture content of 30% to 40%, place scales weighing no less than 0.2 g into the bag and mix with the wet sand or leaf mold, seal the bag opening, and place it in a constant-temperature incubator at 20°C to 25°C; in about half a month, small bulbs will begin to germinate.