Studies On Cultivation And Adaptability Of Several Introduced Colored-leaf Plants

The study focus on 20 colored-leaf plants, which were introduced to Chengdu. The phenological properties and the ecological adaptability, such as temperature, illumination and soil, of those plants were observed. And the propagation techniques of several colored-leaf plants were studied. The result of the experiment shows:1. Phenological observation shows that there is a bit difference in phonological between the first year and the second year that after were introduced to Chengdu,especially in germination or frondesce stage of several colored-leaf plants. Compared with the orininal habitat, florescence of Acer rubrum is 35 days earlier, whereas Abelia grandiflora cv. 'Francis Mason' is about 20 days later, but the ornamental effect of flower ,of the two species, are unchanged. The peak of growth of most of the colored leaf plants come between mid July and mid August, and the plants, in general, grow most quickly in summer, then in spring, most slowly in autumn.2. By observing the ability of those plant wintering ,the result shows that if cold-protection measures should be taken to protect biennial seedlings of Melaleuca bracpeata cv. 'Revolution Gold' and Callistemon formosus, the seedlings should grow up better. It is better to take advantage of plastic film as a shed covering to protect seedlings, but the effect of disposing paclobutrazol and spraying phosphate and potash fertilizer is not so good .The experiment of overing summer and plant diseases and pests show, except that Berberis rhunbergii 'Aurea' and Caryoptris Clandonensis 'worester Gold' ,most of those plants are strong enough to resist diseases.3. Illumination experiment shows that for most of the colored-leaf plants such as Melaleuca bracpeata and Callistemon formosus, when accept whole illumination,the plants can display the beautiful color, if in the 70% of whole illumination, and over 10d,the colorful leafs will turn into green. The shade-tolerant of Trachelospermum jasminoides are strong, which in summer in the 25% of whole illumination, the overall growth of branches and the maximum growth of single branches amount to the peak, the total number of leafs being observed amount to the maximum. Fertilizer experiments show that after applying fertilizer to Melaleuca bracpeata, compare with control ,it has significant change in height, crown, but it has no significant change in leaf color. After applying fertilizer to Callistemon formosus, compare with control, it has no significant change in height, crown and leaf color, which displays its widespread adaptability to the soil. 4. Melaleuca bracpeata cv. 'Revolution Gold' has high rooting rate of cuttings if young banches are used. Disposed of in 30 minutes with ABT1 of concentration 800mg/kg, mixed with 2 oxalic carbon plus 1 pearl rock along with 1 roseite, during the summer time of July and August, the rooting rate of cuttings can amount to 78%. The experiment of the rooting rate of cuttings of Salix Integra cv. 'Hakuro Nishiki' shows that if disposed of in 30 minutes with ABT6 of concentration 600mg/kg,and select roseite as medium , the time should be from mid June to September, the rooting rate can amount to 100%. Acer rubrum has a low the rooting rate of cutting .so it is not successful to Survival. If not disposed of hormone, the rooting rate of Acer rubrum is 0. With 100mg/kg ABT1 treatment for 6 hours; its root rate will amount to 20%.5. The germination capacity of Callistemon formosus are always lower . When the temperature reaches 25℃, the germination capacity is comparatively high, which will amount to 16%. The performance of seeding are orderly, whose index is 11.37. Gibberellin treatment can improves to some extent the budding of the seeds of Callistemon formosus, among which if disposed of with concentration 50mg/kg, the most germination capacity can reach 18%. The germination capacity and germination speed of seeds, if uncovered with soil, is better than that of covered.