The latest course of planting techniques and methods of Yuanhu

Rhizoma Corydalis, also known as Corydalis, is a perennial herb of the genus Corydalis in the poppy family. It is used in medicine with dry tubers, which has the effect of promoting blood circulation and dispersing blood stasis, promoting qi and relieving pain. "Lei Gong gun burning theory" contains "heartache to death, looking for Yuanhu quickly". The Compendium of Materia Medica records: "Xuanhusuo can exercise qi stagnation in blood and blood stagnation in qi, so it specializes in treating all kinds of pain up and down the body."

Botanical characteristics of Rhizoma Corydalis

Rhizoma Corydalis is a perennial herb with a stem height of 10 to 20 cm. Tuber globose, inner yellow. Aboveground stems slender and slightly fleshy, leaves 3-4, leaves 2-Ternate-cleft, ultimate segments lanceolate or narrowly ovate. Racemes, bracts ovate, sepals very small, early deciduous; petals purplish red, 4, arranged in two whorls, outer whorls slightly larger, outermost one extending at the base of the growing moment; inner whorls two narrow, healing. Six stamens, two bodies. The ovary is superior, composed of two carpels and one chamber. Fruit a capsule, flat columnar. The flowering period is from March to April and the fruit period is from April to May.

Biological characteristics of Rhizoma Corydalis

Rhizoma Corydalis grows in mountainous, sparse woodland or grass on the edge of the forest, likes a warm and humid climate and is afraid of strong light. Afraid of drought, can withstand cold. The growing season is short and the demand for fertilizer is high. The strong wind is bad for its growth.

The root system of Rhizoma Corydalis is shallow, which is mainly distributed in the surface soil layer of 1 inch to 3 inches. Tubers generally have 1-2 buds, 3-4 in most, and 1 in less. The optimum temperature for sprouting is 18-21 ℃. In Hanzhong area, seedlings generally begin to emerge after the Beginning of Spring (early February), and end around the Rain and Water Festival (end of February). Seedlings emerge from late January to early February in most parts of the country.

Before the emergence of Yuanhu, the underground stem had already begun to elongate and grew slightly upward along the horizontal direction. The first stem node was formed in late November, and the underground stem was completed by early February. Each species of tuber could grow 2-4 underground stems, each with 2-5 stem nodes.

It takes 100-120 days for the underground stem growth stage from sowing to emergence, followed by the tuber formation stage. There are two parts in the formation of Yuanhu tuber. First, it is formed by the expansion of the nodes of the underground stem, which is used to be called "Ziyuanhu". Usually under the condition of fine planting and adequate fertilization, a tuber of Rhizoma Corydalis can be expanded from the nodes of its underground stem to form more than 10 Yuanhu. However, if there is not enough fertilizer, extensive planting, planting a Yuanhu tuber, can only grow 5-8 Yuanhu. Second, it is developed from the tissue of the seed stem, which is used to be called "Mother Yuanhu". The female Yuanhu began to form from early February to late February. On the other hand, "Ziyuanhu" begins to form from the expansion of the growth node of the stem node, which takes about 50 days, that is, the expansion period of the stem node from mid-March to late April. The peak period of new tuber growth is from late March to mid-April. During this period, the growth of Yuanhu has a direct impact on the harvest yield.

Rhizoma Corydalis is a typical solar plant. The growth is faster and the life span is shorter (the growth cycle is short). From sowing to harvest is only about 210 days, the real growth period is only about 100 days. Therefore, applying sufficient base fertilizer, paying close attention to topdressing, and ensuring the adequate supply of water and fertilizer during the growing period play a decisive role in increasing production. In Dongyang County, Zhejiang Province, medicine farmers believe that the best weather during the peak growth period of Yuanhu in early spring is "three sunny and three rains" (that is, once a week). Therefore, in case of drought in early spring (especially from March to April), irrigation must be given in time (once a week), which is the key to achieving high yield.

According to the above, combined with the study of national Yuanhu production experience, the living habits of Yuanhu can be simply summarized into three sentences: "three joys" (like sunshine, warmth and moisture), "three fears" (fear of stagnant water, fear of drought, fear of continuous cropping), "five no species" (① clayey yellow soil and alkaline soil can not be planted; ② low-lying paddy fields cannot be planted; ③ continuous cropping fields should not be planted; ④ is not suitable for planting without irrigation and drainage conditions. The stem of ⑤ seed cannot be sown without disinfection. Careful selection of suitable growth environment and strict control of the "five passes" are very important to improve the per unit yield of Yuanhu.

Planting techniques of Rhizoma Corydalis

The cultivation techniques of Rhizoma Corydalis can be summarized into four sentences: "shallow, thin, warm and wet". The so-called shallow point, that is, the depth of planting (covering soil) should be 2 inches; sparse, that is, the sowing density should be 2.5 inches square or 2 × 3 inches between rows and plants; warmer, that is, to keep warm for the winter; and a little wet, that is, the side of the box should be kept moist and not too dry.

1. Sorting out the land for use as compartments

Choose the site for ①. To plant Rhizoma Corydalis, we should choose fertile land (field) with deep soil layer, good irrigation and drainage and high soil organic matter content. Sandy loam is suitable, such as sandy mud, semi-sand and semi-mud field, alluvial soil is the best. Dead yellow mud, white loessial soil and gravel soil are not suitable for planting. The physical and chemical properties of soil should be neutral or slightly acidic, and the pH value is usually about 5.6-7.5.

The root system of Rhizoma Corydalis is mainly distributed in the 1-3 inch topsoil layer. The looser the soil is, the more developed the root system is, which is beneficial to the expansion of stem nodes and the absorption of nutrients. Soil consolidation is not conducive to the growth and expansion of stems and branches, the stem nodes are small and the yield is low. If the soil is alkaline, it is easy to form stiff seedlings, grow slowly, and root whiskers (stem branches) atrophy. The soil quality through sand has poor water and fertility conservation, which is easy to form premature senescence, and the growth is inhibited because the sand absorbs heat too strongly, the temperature difference between day and night changes greatly, and the ground temperature exceeds the environment needed by crops.

② prepares the ground. After planting Rhizoma Corydalis, the first step is fine farming. Three ploughing and three harrowing, finishing the topsoil into loose and fine loam, which is the basis for winning Yuanhu to increase production. If there are many large soil blocks in Yuanhu field, it will not only affect seedling emergence, but also hinder root growth, which will seriously reduce the yield in the coming year. Yuanhu field preparation should be combined with sufficient base fertilizer, because the root of Yuanhu is shallow like fertilizer, and the growing season is short, so applying sufficient bottom fertilizer is the key to increase production. According to the analysis of the results of large area high yield experience, better yield can be obtained by applying rotten pig and cattle manure, cruller fertilizer and phosphate fertilizer per mu. If indiscriminate application of cruller fertilizer or direct contact with unrotten fertilizer will cause burning of seedlings, although the seed stem does not change color, nor rot, the bud will stop growing after 1-2 cm of germination. If too much nitrogen fertilizer is applied, it will cause the stems and leaves to grow, lodge in the case of heavy rain, and create favorable conditions for the parasitic reproduction of downy mildew spores, resulting in mass death after infection, resulting in reduced yield. Therefore, in the application of cruller fertilizer, early fermentation is beneficial to the full absorption of Yuanhu root system.

③ acts as a compartment. Immediately after the consolidation of the plot, it is usually appropriate to use the horizontal box, which is beneficial to drainage and irrigation. at the same time, the box surface is short and easy to flatten, which can improve the land utilization rate. The reasonable use area of one mu of land is about eight points. Generally, the width of the chamber is 4 inches, the width of the trench is 7 inches-1 foot, and the depth of the trench is 5-7 inches. The specific structure is shown in the figure:

2. Planting time and method

① seeding time. Yuanhu propagates with tubers and the growth period is short, which takes up only one season of wheat. The profit is big, the output is high, the effect is quick. The planting time is the high yield period between the Autumn Equinox and Cold Dew (that is, from late September to the first and middle of October), and the producing area has the experience of "planting early and applying fertilizer once". If the growth time of the underground stem is less than 100,120 days before emergence, the yield will be significantly reduced when it is postponed to be planted after Frosts Descent.

② seed selection. To choose the medium-sized seed block uniform, flat round yellow no scars, no insect population of the new-born Ziyuanhu as seed. If the selection is too large, the amount of seed will increase. If the old mother and son Yuanhu is used as seed, the reproductive ability is weak, which will affect the yield. According to the requirements of the selected seeds, there are many buds on the tuber, the seedlings are robust and have strong disease resistance.

③ reasonable close planting. When planting in the box, it is more reasonable to plant with a row spacing of 2 × 3 inches or 2.5 inches. It was proved by field experiment that the incidence rate was proportional to the density of the next species. That is, the higher the density, the faster the infection, the higher the incidence, and the more serious the disease. The comparative test results of the following density of 2 inch, 2.5 inch and 3 inch density were as follows: April 11 examination: 2 inch density infection rate was more than 55%; 2.5 inch density infection rate was 20%. 3 inch density infection rate was 10%. April 25 check: density 2 inch seedling 100% 2.5 inch seedling 70% sheng 3 inch seedling 40%. Early seedling return will affect the yield, and delaying seedling return can increase the yield. The reason for excessive density and infection is that the overdensity of aboveground stems and leaves affects the microclimate of Yuanhu border, poor ventilation and lack of light, which relatively increases the humidity of Yuanhu border, and provides a good parasitic breeding environment for the pathogen of downy mildew. therefore, the disease occurs early and spreads quickly. However, it should not be planted too sparsely, and the yield per unit area will decrease.

④ cover soil. A reasonable depth of soil cover should be maintained after planting. It is appropriate to take 2 inches to 2.5 inches. In some cold places in winter, the depth of soil cover can be increased to 3 inches. Because the root system of Rhizoma Corydalis is shallow, such as thin soil cover, few branches of underground stem, short stem nodes, overlapping tubers and low yield. Covering the soil too deep will affect the emergence of seedlings and can not guarantee the whole seedling.

⑤ planting method and sowing amount per mu. First, pull the rope to step on the box on the whole plot, put the seeds on the side of the box according to 2.5 inches square, and sprinkle a thin layer of old wall soil or rotten fine broken farm fertilizer on the set, with a dosage of 2000-3000 jin per mu, 100 jin of oil cake fertilizer and 100 jin of phosphate fertilizer, and then raise the soil in the box ditch to the wing surface with a hoe, which is the cover soil, which causes the shape of the bow. The sowing rate per mu is generally about 120-140 jin, which varies with the seed size.