Taxus mairei

Alias: beautiful yew

Scientific name: Taxusmairei (LemeeetLevl) S.Y.Hu

Family name: Taxaceae of Taxaceae

I. characteristics of tree species

The trunk is straight and the garden is full, the branches and leaves are thick green, and the four seasons are evergreen. it is an excellent greening tree species with hard and dense wood, light yellow sapwood and strong corrosion resistance. it is a special industrial and precious carving material; it can manage medicinal raw material forest and extract paclitaxel and other anti-tumor substances. It is a national first-class precious protection tree species.

Taxus chinensis var. mairei grows slowly and is often mixed with other broad-leaved trees, bamboos and conifers; shallow roots, well-developed lateral roots, drought tolerance, high temperature tolerance, slow growth, like to grow in moist soil rich in organic matter. The canopy density of seedlings and big trees is between 0.5Mel 0.6, which grows well and weakens with the increase of canopy density. The mature period of the seed is from 10 to 12 months, and the seed is red with a hard epidermis. Only after the epidermis is worn off will the seed take root and sprout.

2. Cultivation techniques

1. Seedling raising: at present, sowing and cutting propagation are the main ways to raise seedlings of Taxus mairei.

(1) sowing and raising seedlings: during the seed collection period from October to December, the collected seeds need to remove the outer fleshy aril and wax from the seed shell and then disinfect and store them in sand to break dormancy. The sand storage time in the natural state is 15 months, and the seeds are sown when 80% of the sand is white. Generally, the emergence rate can reach more than 50% after 3 months.

According to the study, the main factor affecting the germination of Taxus chinensis var. mairei is the existence of intraspecific inhibitor, which mainly exists in the seed coat and endosperm. In addition, the impermeability of the outer seed coat also has a certain effect on its germination. It is considered that this inhibitor may have other components besides ABA, and BA can inhibit the activity of this substance to some extent. The sand storage treatment of "warm temperature (25 ℃) stratification for 36 weeks and low temperature 5 ℃ stratification for 12 weeks" can inhibit the activity of substances, complete post-ripening and break seed dormancy, so as to shorten the sowing time and meet the requirements of autumn seed collection and spring sowing.

(2) Cuttage seedling raising: the seeds of Taxus chinensis var. mairei have dormancy caused by post-embryonic ripening. Even if various treatment methods are used, the seeds will not germinate until spring and summer in the third year. The use of branch cuttings can not only increase the source of seedlings, but also maintain the excellent characters of the mother plant, and the main factors affecting the rooting rate of Taxus mairei cuttings: ① panicle age and component phenotype: the cuttings are better for current-year and 2-year-old branches; sprouting vines or cutting on old stems and branches are beneficial to the development of robust tree type. ② cutting habitats and facilities: at present, low greenhouse shading and nursery film mulching are commonly used in production to keep warm and moisture. the seedling bed temperature is generally 2030 ℃, humidity 80% muri 90%, transmittance 25% Muir 35%, which can be adjusted appropriately in winter and summer. ③ hormone treatment and time: soaked in ABT1 No. 2 100ppm and No. 8 10ppm, indolebutyric acid 500ppm, indole acetic acid 100ppm for 4 hours, rooting powder, indolebutyric acid or indole acetic acid and talc powder could also be adjusted into paste, and the cuttings were dipped in medicine at the base of the spike, but the best soaking time was indole acetic acid (IAA) 100ppm for 1 hour. ④ cutting substrate and cutting length: Taxus chinensis var. mairei can grow normally on a variety of single or combined substrates, such as river sand, saw bran, perlite, yellow core soil, (stone to) stone, loam and so on. The mixed substrate of 46% perlite and 54% yellow core soil is the best for 8cm cuttings, and perlite is the best for 5cm cuttings. Cuttings of 10cm and combination of sand, perlite or yellow soil and sawdust are commonly used in production. ⑤ cuttage season: autumn is better for hardwood cuttage, and softwood cuttage can be carried out in the whole growing season theoretically, but production generally needs to avoid the hot summer, mostly in April-May.

2. Afforestation: the opposite site condition of Taxus chinensis is high, and the afforestation site should choose the shade with deep and fat soil. There are mainly two afforestation modes: interplanting under ① canopy: using large diameter wood base of Cunninghamia lanceolata and Pinus massoniana and Phyllostachys pubescens forest (canopy density is controlled at about 0.5). ② according to the experience of Mingxi County, afforestation 1000 trees / mu in the field, the purpose of afforestation is to extract paclitaxel, pay attention to shading, moisturizing, no stagnant water.