Cultivation techniques of Artemisia annua L.

The plant of Artemisia annua is 40ml 150 cm high, and the whole plant has a strong smell of volatile oil. Stem erect, longitudinally striate, much branched, smooth glabrous. Basal leaves flat on the ground and withered when flowering; cauline leaves alternate, green when young, yellowish brown when old, glabrous, shortly stalked, gradually sessile upward; leaf blade usually pinnatifid, lobed leaves short, with minute powdery pubescent, dark green above, light green below, with fine hairs or powdery glandular spots; leaf rachis narrowly winged on both sides; leaves on the upper part of the stem gradually finely striate upward. Small yellow flowers bloom in late autumn, heads small, globose, ca. 3.6 mm in diameter. With slender short pedicels, mostly conical; involucre small globose, flowers all tubular, yellow, periphery female flowers, central bisexual flowers, achene, ellipsoid. The flowering period is from July to August and the fruiting period is from September to October.

In addition, the genus Artemisia annua and its variety Artemisia annua L. The difference between the two and Artemisia annua is that the leaf is tripinnately divided, the central axis is not pectinate, the final lobule is short-pointed, easy to break, and the cross-sectional pith is larger. The head is spherical and dense, 1.5 mm in diameter for Artemisia annua, and 3 mm in diameter for Artemisia annua.

(growth habits)

1. Biological characteristics

The main results are as follows: (1) the weight of 1000 seeds is 0.02-0.048 mg, and the seed weight is 4500Mel 5000 per gram. Seed germination requires light or variable temperature. Under light, the seeds germinated at 15 ℃-25 ℃, and the seed germination rate was 99%; the germination rate of seeds below 15 ℃ or above 30 ℃ was low.

(2) during the growth period, sowing in the first ten days of March (10.5 ℃), seedlings emerged in 7 days, and the first pair of true leaves grew in 12 days. The growth accelerated 40 days after emergence, the seedling height was 18 cm, the stem appeared at 80 days, the first branch appeared at 39 cm, and entered the second branch in mid-late June. It takes 130 days from the first branch to budding, flowering after 170 days (from the beginning of August to the end of September), ripening in 200days (from the end of September to the first ten days of September) and falling seedlings (5 ℃-8 ℃) in 260days (the end of December). The whole growth cycle is 265 days from sowing to leaf harvest.

(3) the root growth of Artemisia annua is a shallow root plant, with short main roots and developed lateral roots, with a depth of 16 cm and a root width of 20 cm.

(4) the germinating ability of branching habit branches is strong, which can reach 76 murine 90 lateral branches. From germination to the appearance of lateral branches, the main stem grew slowly; before the end of May, the stem thickened and grew faster; from the first ten days of August to the middle of August, the second peak appeared; the growth stopped when it entered the flower bud stage in early September. Dry leaf weight and artemisinin content increased with the extension of growing period.

(5) the flowering habit is the initial flowering stage in mid-September, the full flowering stage in late September, and the late flowering stage at the end of September. The order of flowering is from bottom to top, the same branch opens upward from the stem, and the same inflorescence opens from outside to inside. The flowers are tubular flowers, female flowers in the periphery and bisexual flowers in the center. The self-pollination rate is 5%, which is a cross-pollinated plant.

(6) stress resistance has strong biological competitiveness. It grows fast after the first branch, and forms a plant community dominated by Artemisia annua with an overwhelming advantage over weeds. It has strong resistance to stress, drought, waterlogging and epidemic disease.

2. Requirements for external conditions

Artemisia annua is widely distributed, often wild in the wilderness, hillsides, roadsides, riverbanks, houses. After harvest, cornfield, rape land or second wasteland grew the most, followed by ripe land, and wasteland for many years was less.

The main results are as follows: (1) Artemisia annua L. has strong adaptability to air temperature. The content of effective component (artemisinin) of Artemisia annua growing in the middle altitude area of Enshi Prefecture is higher than that of northern Artemisia annua L. The growth of Artemisia annua with higher content was mainly distributed in the zone of 10.4 ℃-14.9 ℃ and accumulated temperature in the range of 4627.2 ℃-5212.7 ℃. Seed germination requires variable temperature, and the germination rate under the condition of variable temperature is higher than that at constant temperature. At 20 ℃-27.5 ℃, the stem and bud grows rapidly, and the content of effective components increases rapidly.

(2) from water heading to budding stage, the average precipitation is about 200 mm, and the relative humidity is 80%. It grows vigorously in the zone of high temperature and humidity.

(3) sunlight with temperature of 30 ℃, light intensity of 1000 mi 2000 and light periodicity of 12:12 hours can promote the early ripening of Artemisia annua, and the active components are high and stable. The sunshine hours from branch to bud stage were longer, 156.5-169.4 hours / month, and 185.3 hours / month at flowering stage. Artemisia annua is a short-sunshine plant, which requires about 1000 hours of light per year, which is not suitable for too much or too little. Artemisia annua can grow with too much or too little light hours, but it will lead to the decrease of artemisinin content.

(4) soil Artemisia annua should choose sunny and moist alluvial soil or purple-red soil with Permian gray thick limestone parent material. The effective content of Artemisia annua grown in yellow loam is low, so it is not suitable for planting.