Duanzhou Mountain Dendrobium

Duanzhou Mountain Dendrobium

Duanzhou Mountain Dendrobium is an agricultural product with geographical indication status.

　　Duanzhou Mountain Dendrobium is a specialty of Rong County, Yulin, Guangxi.

　　1. Morphological Characteristics

　　Dendrobium is a perennial epiphytic herbaceous plant of the Orchidaceae family. Its stem is upright and cylindrical, measuring 5–35 cm in length and 0.3–0.6 cm in diameter, with internodes 1–2.5 cm long. It features purple longitudinal stripes and is purplish-red or yellow-green in color. The one-year-old stem is semi-transparent when held up to the light, revealing internal fibrous strands. It is multi-jointed, with stem nodes ranging from iron-blue to black in color, hence also known as "black-jointed herb." The nodes bear scars from flower stalks and remnants of leaf sheaths. The leaves are alternate, numbering 3–20, with young leaves being purplish-red and mature leaves yellow-green. They grow on the upper part of the stem, arranged in two rows, and are oblong-lanceolate in shape, measuring 3–7 cm in length and 0.8–2.0 cm in width. The leaf tips are blunt with slight hooks, and the base extends downward into a sheath that clasps the stem. The leaf edges and midrib often have a light purplish tint. The leaf sheaths are gray-white with slight purple speckles, slightly open at the mouth, clasping the stem but not extending beyond the previous node, usually leaving a ring-shaped gap. They are hard and brittle. The inflorescence is a raceme, growing at the upper end of leafless stems, measuring 2–4 cm in length, and curved in a recurved shape. There are 1–3 flowers per internode, pale yellow to white with a faint fragrance. Each flower is about 1.5–2.0 cm in diameter, labiate in shape, with one petal modified into a lip. The Dendrobium flower has the pistil and stamen fused into a typical columnar structure, with the pistil located below and the stamen above. Each flower has four pollen grains, with an almost oval-shaped anther cap that splits open at the center. The flower bracts are pale white, the tepals yellow-green, the lip ovate-lanceolate, 1.6 cm long, white on the upper half with a large purplish-red blotch, and the lower sides featuring purplish-red streaks. The median sepal resembles the petals, being oblong-lanceolate, 1.7–1.9 cm long and 0.4–0.5 cm wide. The lateral sepals are about 1 cm wide. The ovary is conical, 0.5 cm long, densely covered with papillate short hairs on the disk, with a single yellow callus at the base. The Dendrobium fruit is an elliptical capsule, 3–5 cm long, turning yellow-green when mature. Each fruit contains tens of thousands of seeds, which appear yellow-green under a standard optical microscope, with winged ends and a long spindle-like shape. The seeds measure 0.4 mm in length and 0.09 mm in width.

　　2. Ecological Habits

　　Dendrobium is mainly distributed in provinces such as Yunnan, Anhui, Guizhou, Guangxi, Zhejiang, and Guangdong within China, and is also found in Tibet. It has strict requirements for its ecological environment and mostly grows as an epiphyte on rocks at forest edges or on broadleaf trees with thick trunks that are covered in moss and wild vines, at altitudes of 2100–2500 meters. It prefers cool, moist environments and typically coexists with lichens, ferns, and mosses. It thrives in environments where the relative humidity of the air exceeds 70%, with an annual average growth temperature of 17–22°C. The temperature difference between the coldest and hottest months is not significant, with January’s average temperature staying above 10°C, a frost-free period of 250–250 days, and annual rainfall exceeding 1000 mm. It exhibits tolerance to drought and cold. The flowering period mainly occurs from May to late June, lasting 3–6 months. The seed pods mature progressively from early October to February of the following year. Dendrobium seeds are extremely small, with incomplete embryonic development and no endosperm tissue, resulting in very low natural germination rates. Sexual reproduction is highly difficult, and propagation mainly occurs asexually through continual root division from the base or new plants sprouting from roots formed at upper stem nodes. The stem's lifespan is generally three years. In March to early April, axillary buds at the base of second-year stems sprout into seedlings—each mother stem can produce 1–3 new shoots, and harvesting typically takes place in the autumn or early spring of the third year.

　　Region:

　　Guangxi

　　Applicant:

　　Guangxi Rong County Golden Land Dendrobium Planting Professional Cooperative

　　Region:

　　2013

　　Coverage Area

　　The protected area for Duanzhou Mountain Dendrobium is located in the southeastern part of the Guangxi Zhuang Autonomous Region, between 110°15′–110°53′ east longitude and 22°27′–23°07′ north latitude. It spans a maximum east–west width of 51 km and a maximum north–south length of 73.5 km. To the east it neighbors Cenxi City, to the northeast it connects with Teng County, to the south it borders Xinyi City and Beiliu City of Guangdong Province, to the west it adjoins Beiliu, to the northwest it lies next to Guiping, and to the north it connects with Teng County and Pingnan County. The easternmost point is Yuguishan at the eastern end of Dapo Chong, the westernmost is Dadong and Chenchong at the western end of Shitou, the southernmost is Gouji Mountain at the southern end of Lichun, and the northernmost includes villages such as Datianxu, Pingshan, and Guxie. The protected geographical indication area for Duanzhou Mountain Dendrobium agricultural products includes 15 towns and their 219 administrative villages: Rongzhou Town, Rongxi Township, Shili Township, Shizhai Town, Yangmei Town, Lingshan Town, Liuwang Town, Lichun Town, Yangcun Town, XianDi Town, Ziliang Town, Langshui Township, Songshan Town, Luojiang Town, and Shitou Town.