1. Species of Amomum villosum available at present
(1) Green shell sand
perennial herb, 1-2 meters high, with reddish underground stems, which can reach 1 meter horizontally along the surface of the ground. The nodes are covered with tubular membranous phosphorus sheets, and many adventitious roots are born. The underground stems germinate slightly upwards, and a large number of fibrous roots are born downwards to form ramets. The ground is upright and unbranched. Leaves dichotomous, sessile, leaf sheath phimosis, and leaves are long, narrow, round or linear-lanceolate. In spring, spherical spikes are drawn from underground stems, which bloom from April to May, with pale yellow spots. Capsule is spherical or elliptical, slightly triangular, green in appearance and spiny. Most seeds are triangular, black when ripe, and mature from August to September.
(2) Red-shell sand
is different from green-shell sand in that the leaves are larger, the back of the leaves is fluffy, the fruits are smaller, round and red in appearance, and the fruit yield is higher, but the quality is poor, so it is not cultivated much.
(3) Amomum villosum
is different from green shell sand in that the capsule is purple-brown, and the underground stem is more red than green shell sand. This variety is of good quality and is the main circulating variety in the market.
2. Plant growth characteristics
Amomum villosum is a tropical plant, and likes high temperature, humid and foggy climate. The average annual temperature is 22~38℃, but it can still grow through the winter in case of short-term low temperature or occasional short-term frost, especially in the flowering and fruiting period, where flowering is abnormal below 22℃, and pollination is beneficial above 25℃, with high fruiting rate. Shading degree of 5%~7% is appropriate, but the seedling stage needs a larger shading degree of 7%~8% for 1~2 years. During the fruit-setting period of Amomum villosum, and when the soil is clay loam or loam, the shading degree is 5%~6%, and when it is sandy loam or dry land, the shading degree is 6%~7%, and some nectar source trees are planted to attract insects to spread pollen. Amomum villosum likes to diffuse light, and direct strong light is not good for growth and development; If it is too shaded, the plant will grow vigorously, but it will blossom and bear few fruits. The requirement for moisture is particularly strict. The annual rainfall should be about 2 5 mm, and the annual average air relative humidity should be above 8%. Especially in the flowering period, it is foggy and the soil temperature is high (the soil water content is about 2%). On the contrary, in case of continuous rain, flowers will rot, and prolonged drought will make flowers dry and fruits not full, which will reduce the fruiting rate. The requirements for soil are not strict, and the soil with loose and fertile surface, strong water retention and convenient irrigation and drainage is suitable.
3. Cultivation techniques
(1) Land selection and soil preparation
According to the requirements of Amomum villosum on environmental conditions, it is advisable to choose fertile valleys that can be kept moist or foggy and well drained from March to May or low hillsides where streams flow, and broad-leaved evergreen trees with large crown, deep roots, perishable leaves and strong water retention should be selected as shade trees.
prepare the soil one month before planting, and select shade trees to keep the shade degree between 5% and 7% (young trees should be selected if the shade degree is not enough, and appropriate thinning should be done if the shade degree is too large). Remove weeds and cut down shrubs that don't need to be shade trees. Then ploughing for 14-33cm to make the soil weather, breaking large clods and leveling before planting; If it is on a slope, a drainage ditch should be set up to prevent soil erosion.
(2) Propagation methods
The propagation of Amomum villosum can be carried out by seed propagation and ramet propagation.
① seed propagation. Seed selection and treatment. Amomum villosum seeds should go through "three selection" procedures. First, Amomum villosum seeds with high yield over the years should be selected from high-yield varieties, and seed fields should be established. When the fruits are ripe, the mother plants with strong plants and no pests and diseases should be selected, and the ear with large ears and many grains should be selected as seed seeds. Only through such strict selection can a good variety be selected. Generally, the seed ripens around the summer heat, the exocarp is reddish brown, the pulp is as sweet as litchi meat, and when the seed turns black, it is fully mature. Take off the compost for 3~5 days, remove the peel, put it in clean water, add oil sand or chaff, rub off the pulp by hand, change the water several times, wash off the gum sugar, dry it in the shade, and immediately sow it in autumn. Because the seeds are fresh from August to September, the temperature is high and the emergence rate is uniform. Spring sowing is stored in wool cans and the shells are dried as commodities.
② the arrangement of Miao Di. Choose a shady, humid, ventilated and cool environment, fertile and loose land and convenient drainage and irrigation as the nursery ground. One month before sowing, dig deeply and turn over the sun to weather the land. When sowing, the clods will be finely plowed, and the border will be raised from the flat ground, with a height of 1-12 cm, a clear surrounding ditch and a width of 8-1 cm. In order to facilitate the construction of shade shed, weeding and watering management, the border should not be too wide, and it is best to start from the north to the south, which is beneficial to build a shade shed with its back tilted from west to east and control the sunshine in the afternoon in the west. After the border surface is finely ground and leveled, the pit is opened with a row cutter (row cutter method: 1 wooden tooth harrow, teeth are 12 cm apart, teeth are 3 cm wide and 3 cm long), and 1.5 tons of human manure and water fertilizer are applied to the bottom of the pit per mu as base fertilizer, and then sowing is carried out.
③ sow in time. Sowing is divided into spring and autumn. Spring sowing is in the middle or late March, and autumn sowing is in late August to early September. Autumn planters germinate quickly and orderly, and the germination rate reaches 6% ~ 7% 2 days after sowing. Sowing methods mostly adopt row seeding, with row spacing of 12-15cm, plant spacing of 4.5-6cm and sowing depth of 2-3cm. The sowing amount per mu is 2.5~3 kg or 4~5 kg of fresh fruit. Generally, autumn sowing is adopted, and spring sowing is seldom used.
④ sowing method. There are methods such as row sowing and on-demand sowing, in which the seeds are sown evenly in rows, which is convenient for watering, weeding and fertilization management, and the row sowing is mostly used. Spring sowing seeds are dried. Before sowing, the seeds are soaked to accelerate germination, germinate in advance and germinate uniformly. When accelerating germination, soak the seeds in cold water for 1-2 hours, then soak them in warm water at 45℃ for one day and night, and then take them out and air them to be planted.
When sowing, sow seeds with row spacing of 13cm and plant spacing of 8cm, and the sowing amount per mu is 1kg (fresh fruit is about 4-5kg). After sowing, cover with base fertilizer (the base fertilizer is mixed with soil miscellaneous fertilizer, cow urine chaff, chicken excrement, plant ash, etc., and then it is decomposed by mixing and retting), and it is appropriate to apply 1.5~2 tons per mu, covering the seeds by 3 cm. If the base fertilizer is too thin, fine soil can be sprinkled, chicken manure can be applied, and there are many pests, and lime should be sprinkled into the pile to decompose and kill the pests before application.
⑤ seedling management
immediately after sowing, set up a shade shed to make the shade degree reach 8%, and always keep the soil moist and pay attention to drainage in low depressions. Young plants are most afraid of weeds, so weeding should be done early, small and weedy. If the seedlings are too dense, when the height of the seedlings is about 3 cm, the seedlings should be thinned by weeding and loosening the soil, and thin human excrement and urine should be applied. When the height of seedlings is 15 cm, the spacing between plants is 6~12 cm, and soil is cultivated and mixed fertilizer is applied to promote the germination of roots. At this time, the shading degree can be gradually adjusted to reduce it to about 6%. Seedling height is 3~45 cm, which can be transplanted and planted.
(2) Plant propagation
In the production area of Amomum villosum, select 5-1 thick leaves, annual seedlings with two new underground stems, plants with strong growth and many flowers and fruits, cut off at 12-15 cm of the underground stem of the mother plant, separate new plants, trim some long roots and leaves, and place them in a shady and humid place. Ramet propagation can bear fruit early.
(3) Planting
Places with good water conditions (which can keep the soil moist) can be planted in March, and places that cannot meet the water conditions will be planted in May-June when the rainy season comes.
it is advisable to choose cloudy or light rain weather for planting, dig holes according to the spacing between rows and plants of 1m× 1m, apply decomposed animal manure or compost as base fertilizer in the holes, plant the seedlings according to their natural conditions, with the red buds slightly exposed, and bury the rest in the soil, slightly compact them (to prevent the young buds from being damaged), and water them if there is no rain after planting.
4. Field management
1-2 years after field planting, Ying Qin will weed, loosen soil, apply fertilizer, and properly cultivate soil. Three years into the fruiting period, management will be difficult, and tender stems will be easily injured. Weeding and fertilization can be done once before flowering in March to promote flowering and fruiting. Fertilization depends on local conditions, and it is best to apply water and fertilizer in dry season. After fruit picking in September ~ October, weeding and fertilization should be carried out for the second time, and dead branches and weak seedlings should be cut off. If possible, irrigation and artificial pollination should be carried out at flowering stage, which is beneficial to flowering and fruiting and improving yield.
with the growth of shaded trees, such as over-shading in the forest, the branches should be thinned appropriately to adjust the suitable shade. At the same time, these shady young trees are kept to replace bad shady trees.
fertilization in spring and autumn is the key to increase the yield of Amomum villosum: fertilization in autumn can promote the differentiation of flower buds and lay the foundation for increasing the yield in the coming year, while fertilization in spring can strengthen flowers, increase pollen and improve the fruiting rate. Therefore, it is urgent to fertilize Amomum villosum every spring.
According to the growth habit of Amomum villosum and the experience over the years, Amomum villosum should be fertilized twice in spring: once about 3 days before flowering and once again 5-6 days before flowering. According to the calculation of 5 kilograms of fresh fruit per mu, it is generally necessary to apply 2 kilograms of urea, 3 kilograms of calcium magnesium phosphate fertilizer and 1~15 kilograms of potassium chloride per mu. For the first time, 7.5 kg of urea and 15 kg of phosphate fertilizer were mixed and applied; For the second time, 12.5 kg of urea, 15 kg of phosphate fertilizer and 1~15 kg of potash fertilizer were applied in a mixed way.
It should be noted that the fertilizer applied will only dissolve after the rain soaks through the vegetation, so that it can be easily absorbed by Amomum villosum seedlings; Fertilization in dry land, if the concentration of chemical fertilizer is too high, will burn seedlings, resulting in reduced production or loss of harvest, so artificial irrigation can be used after fertilization in dry days. In addition, before fertilization, the garden must be cleared, the dead, weak and diseased seedlings must be cut off, and the leaves on the planting ground should be covered net to facilitate the growth of Amomum villosum and artificial pollination.
5, pest control
(1) Rhizoctonia solani
occurs at the seedling stage, mostly in March-April and October-November, which makes the seedling base shrivel and dry and die. It can be controlled by spraying 1∶1∶(12~14) Bordeaux solution or pouring with 2~4 times of quintozene solution.
(2) Leaf spot disease
occurs at seedling stage, and leaves are waterlogged at the initial stage of the disease, with no obvious edge, and then the whole plant dies.
treatment: clean the seedbed and burn the diseased plants; Pay attention to the ventilation and light transmission of the seedbed to reduce the temperature; Apply more phosphorus and potassium fertilizer to enhance disease resistance; Spray with 1∶1∶(12~16) Bordeaux solution or 1 times solution of Dyson ammonia water once a week for 3~4 times in a row.
prevention methods: pay attention to drainage, ventilation and light transmission, and apply less nitrogen fertilizer during flowering and fruiting; Lime and plant ash (1 lime to 2~3 plant ash) were applied once each in March and October ~ November, with 15 ~ 2kg per mu; Spraying fruits and stolons with 1% formalin or .2% potassium permanganate solution (5 kg per mu) during the flowering and fruiting period, spraying lime and plant ash at a ratio of 1: 4 after each spraying, and spraying for 3-4 times.
(3) Worm. In order to harm young bamboo shoots (seedlings without leaves), the apex of the killed young bamboo shoots dried up and finally died.
control method: adults can be sprayed with 4% dimethoate EC 1 times or 9% trichlorfon powder 8 times during spawning period.
Keep away from the harm of animals and birds. The fruit of Amomum villosum is seriously damaged by rats, so it can be lured and killed with zinc phosphide mixed with food. If there is harm from animals and birds, it can be controlled by hunting.
6. Artificial pollination
The flower of Amomum villosum is a typical insect-borne flower, which cannot pollinate itself. Under natural conditions, it must be pollinated by insects to bear fruit. In areas where many insects collect powder, the natural fruiting rate reaches 3%~4%, and some even reach 6%~8%. Therefore, artificial pollination can greatly improve the seed setting rate and yield of Amomum villosum in places where insect pollination is less.
artificial pollination generally adopts push-pull method. Hold the big petals and stamens with the middle finger and thumb of your right hand or left hand, and gently push the pistil down with your thumb, and then pull it up. A large amount of pollen can be stuffed into the stigma hole by pushing and pulling, which can be carried out from 7 am to 4 pm every day.
7. Harvesting and processing
Generally, the fruit of Amomum villosum is ripe from mid-August to mid-September, so it should be harvested in time, which will affect the quality too early and be harmed by wild rats too late. Use a small knife to cut the ear of fruit, but don't pull it by hand, so as not to tear the rhizome and affect the growth of Amomum villosum. After harvesting, the fruit is picked and processed into shell sand, Amomum villosum and sand shell according to different varieties.
(1) Shell sand
Put the fruit in a bamboo sieve, dry it with fire until it is 6% dry, spray cold water once to make the peel and seeds closely combine, continue drying or pour it into a sack when it is 8% dry, tighten the bag mouth, moisten it for 12 hours, and then slowly dry it with low fire.
(2) Amomum villosum
Peel off the seed balls of the pericarp, and dry them in the sun or oven. Note that when drying or baking, turn it gently to prevent loose particles.
(3) peeling the peel from the sand shell
and drying in the sun.