Cultivation techniques of Elsholtzia splendens

Elsholtzia splendens, alias coriander, Xiangrong and so on. It is used in medicine with dried aboveground parts with flowers. It is a commonly used traditional Chinese medicine, which has the effect of sweating, dispelling summer heat and resolving dampness, promoting diuresis and reducing swelling, warming the stomach and regulating the stomach. The main treatment of summer cold drink cold, headache and fever, aversion to cold without sweating, chest ruffian abdominal pain, vomiting diarrhea, edema, beriberi and so on. The volatile oil content of the whole grass is 0.61.8 and has broad-spectrum antibacterial activity. It is planted in Liaoning, Hebei, Shandong, Henan, Anhui, Jiangsu, Zhejiang, Jiangxi, Hubei, Sichuan, Guizhou, Yunnan, Shaanxi, Gansu and other places.

I. growth habits

Elsholtzia splendens like to grow in a warm, humid, sunny and rainy environment. The adaptability to the soil is not strong, the general soil can be planted, but the fertile clay soil or red loam soil is better. When the soil moisture is suitable, the temperature is about 15-18 ℃, the seeds of Elsholtzia splendens emerge 10-15 days after sowing, and the optimum growth temperature is 25-28 ℃.

After sowing in spring, the growth and development is slow due to the low temperature, and the growth is accelerated gradually with the increase of air temperature. The period from July to August is not only the exuberant period of Elsholtzia splendens growth, but also the season of accumulation of active components. The florescence is from June to July and the fruiting period is from September to October.

II. Land selection and land preparation

Elsholtzia splendens has strong adaptability, so it is appropriate to choose sandy loam soil with loose texture, shelter from the wind and good drainage, and red soil with loose texture on hilly slopes. Ploughing before planting, the soil is fully weathered, according to the soil type and fertility condition, the rotten barnyard manure or compost 2000-2500kg/u is applied as base manure, and the soil is turned 15-20cm into a fine level, generally two ploughs and two harrows, and then make a border with a width of 120-150cm and a height of 12-15cm, with a width of 25-30cm, and a turtle back shape on the border surface, sprinkled with 375-450kg calcium magnesium phosphate fertilizer per hectare, and then covered with broken soil.

Third, sowing seeds

It is suitable for sowing in late March and in the first half of April, and summer sowing can be carried out in June.

1. Seed selection and retention

The disease-free robust plants were retained from late September to early October and harvested when the seeds were fully mature. It is best to choose a sunny morning, harvest with dew, the seeds are not easy to fall. Cut off the roots of the extracted plants and put them back on the cement field or mats until 80% dry, cuff the seeds with small sticks to make the seeds fall off, remove the impurities, dry them, store them in a pot and place them in a ventilated and dry place.

2. Sowing method

It can be broadcast on demand, strip or broadcast, and the strip broadcast is good for easy management.

When sowing, mix the seeds with plant ash and choose sunny or cloudy days. According to the row spacing of 3-5cm × 3-5cm, the row spacing is 20-25cm, the shallow trench is deep 2cm, and the seeds are sown evenly in the ditch. The density should not be too high, and the seeds should be pressed slightly after sowing to make the seeds close to the soil to facilitate the emergence of seedlings. The sowing rate is 1.5-2kg/u. After sowing, the fine soil sifted with fine soil mixed with plant ash or fire ash is about 1cm thick. The seeds can sprout after 1-2 weeks.

IV. Field management

1. Interseedling and fixed seedling

After the emergence of Elsholtzia splendens, it is necessary to have time for seedlings, the density is sparse, and the weak is strong. Generally, the first interseedling was carried out when the seedling height was about 5cm, and then 2-3 times according to the growth condition, and the seedlings were fixed when the seedling height was 10cm.

2. Ploughing and weeding

Elsholtzia splendens should be ploughed and weeded for 4-5 times in the whole growing period, and the weeds should be pulled out in time after emergence. The principle of pulling small and pulling should be taken as the principle to prevent weeds from competing with Elsholtzia splendens for nutrients, and be careful not to damage the roots.

3. Fertilization

Elsholtzia splendens has a short growth period, so it is necessary to topdressing in time, mainly organic fertilizer, and pay attention to the combined application of organic fertilizer and inorganic fertilizer. On the basis of sufficient basal fertilizer, the first topdressing was carried out when the seedling height was 5-10cm, and the third time was carried out before heading, with urea 120-150kg per hectare, sprinkled on the border, or urea dissolved in water, urea 11.2kg per hectare. In the future, fertilizer should be applied properly depending on the growth of the seedlings.

4. Irrigation and drainage

Elsholtzia splendens like to be wet, but they are afraid of stagnant water in their roots. In the seedling stage, water should not be too much, if the rainfall is too large, ditches should be opened in time to avoid stagnant water in the field. Elsholtzia splendens need the most water before and after flowering. In case of drought, they should be irrigated properly to ensure an adequate water supply.

Prevention and control of diseases and insect pests

The main disease of Elsholtzia splendens is root rot. It occurs in the root and rhizome. At the initial stage of the disease, brown plaques appear in the root and root neck, which expand by Zhejiang, and the base of the main root and stem become dark brown. In the later stage of the disease, the lower leaves of the plant atrophied, yellowed and died, and developed upward in Zhejiang. The pathogen belongs to the genus Fusarium oxysporum. The hyphae overwintered in the diseased body or soil, the disease began in April, and the peak period was in May, which was re-infected by Rain Water or irrigation water. Prevention and control methods: the agricultural comprehensive control measures of "prevention first, comprehensive prevention and control" were adopted. First of all, strengthen cultivation management, clear the garden in winter, remove diseased leaves or diseased leaves in time, eradicate weeds, concentrate on burning or deep burial treatment, in order to reduce the source of bacteria. Do a good job in the rainy season to clear ditches and drainage, prevent stagnant water, and remove diseased plants in time to prevent spread. Chemical control can be controlled by spraying 50% carbendazim 500 times liquid, spraying every 7-10 days, spraying 2-3 times continuously or 50% carbendazim wettable powder 1000 times irrigating root.

The insect pests of Elsholtzia splendens are mainly small land tigers. In order to harm the larvae, the young leaves of Elsholtzia splendens seedlings were eaten at the young stage and bitten into concave spots, holes and lacunae. After the 3rd instar, the larvae sneaked into the soil surface and broke the tender stems, causing the seedlings to wilt and die, resulting in lack of seedlings. 6-7 generations can occur in a year, which begins to appear in mid-late February, two breeding peaks appear in mid-late March and early-middle April, and the damage peak is from late April to early May. After late June, adults begin to Eclosion and gradually decrease in the field. Control methods: in the dangerous period of the advanced instar larvae, check in the field in the morning and find that the newly wilted or bitten seedlings can be removed from the topsoil to kill the larvae artificially. In the low instar stage, 50% phoxim EC 1000 times and 90% crystal trichlorfon 1000 times were sprayed with 75kg/u, once every 7-10 days, 2-3 times in a row. You can also use 50% phoxim EC 200mL/u, mixed with moist fine soil 30kg to make poisonous soil, spread it along the ridge near the seedling rhizosphere in the evening, or use 90% crystal trichlorfon 200g or 50% phoxim EC 200mL, add appropriate amount of water, mix cottonseed cake 5kg, and make poison bait for better control effect.

VI. Harvesting and processing

Spring sowing was harvested in mid-late August and summer sowing in early and mid-September. When Elsholtzia splendens were harvested at the flowering stage, the volatile oil content was the highest.