Organic cultivation techniques under grass coral forests

Organic cultivation techniques under grass coral forests

Fund Project Guangxi Agricultural Science and Technology Self-financing Project (Z201994).

_ Blue Songtao, etc

Grass coral ( Sarcandra glabra ( Thunb. ） Nakai. Also known as swollen knots, nine knots of tea, elderberry, etc., it is a perennial evergreen half-shrub of the genus Golden Millet Orchid, which is a Chinese herbal medicine commonly used to treat bruises, low back pain, stomach pain, wound ulceration and other symptoms. With the increase in the benefits of grass coral planting, the planting area has also been expanding in recent years, in this process, many growers in order to pursue yield, excessive use of pesticides and fertilizers, resulting in forest land destruction, environmental pollution and grass coral quality decline and other issues.

Organic Chinese herbal medicines are plant Chinese medicinal materials or Chinese medicine tablets that are produced and processed according to the principles of organic agriculture and the production methods and standards of organic products, and are certified and issued by legal organic product certification bodies. Organic cultivation of grass coral can avoid the use of highly toxic pesticides, chemical fertilizers, plant growth regulators, and can also be harvested in advance or delayed, which greatly protects the physical safety of consumers and promotes the healthy development of the traditional Chinese medicine industry. If it is not processed according to the norms, it will lead to the loss of authenticity of medicinal materials, low quality, pesticide residues and heavy metals exceeding standards.

Grass corals like shade, avoid strong light and drought, fir forest, moso bamboo forest, fast-growing eucalyptus forest, camellia oleifera forest and other understory environment is suitable for grass coral growth, so the planting of grass coral under the forest has been greatly developed. At present, more than 70% of the grass corals are planted in the hills and mountains of Jiangxi, Fujian, Guangdong, Guangxi, Hunan and other places. The organic cultivation of grass coral under the forest needs to coordinate the growth of grass corals and forest trees, reduce the use of chemical fertilizers and pesticides, and achieve a balance between ecological benefits and economic benefits. At present, there is less research on the organic cultivation technology of grass coral, this paper combines the organic planting standards and requirements of Nanjing Guohuan organic agriculture, studies the organic planting technology of understory grass coral, and summarizes the organic cultivation technology of grass coral under the forest, in order to better promote the development of grass coral industry in the direction of high efficiency, environmental protection and high quality.

1 Site selection and planning

1.1 Site Selection Requirements

Grass corals should be planted far away from urban areas, industrial and mining areas, traffic trunk lines, industrial pollution sources, domestic garbage dumps and other places, pollution-free areas with convenient transportation, and for production bases in adjacent industrial areas, atmospheric samples should be collected for pollutant analysis. The concentration of contaminants must be lower than the corresponding environmental quality standards and food hygiene standards on the mainland. If there are or potential sources of pollution around, practical measures must be taken to ensure that production is not affected. There should be sufficient water sources such as reservoirs, rivers, streams, mountain springs, and groundwater near the planting area, and the quality of the water sources must meet the corresponding requirements in the "Farmland Irrigation Water Quality Standards" (GB 5084 - 2005). You can choose undeveloped primary forests, eucalyptus trees, fir trees, camellia oleifera, moso bamboo, fire nan and other trees with a depression of about 0.7, and there can be no genetically modified organisms and their derivatives in the forest, including plants, animals, seeds, pollen, propagating materials and fertilizers, soil improvement substances, vaccines, plant protection products and other agricultural input substances. If the above trees are conventionally produced trees, it takes a 3-year conversion period to achieve the conditions for organic production.

1.2 Planning Requirements

A forest buffer zone of 8 to 10 m wide is set up around the organic production area to avoid pollution caused by neighboring villages and conventional production areas. In the organic production area of grass coral, drip irrigation or sprinkler irrigation facilities are installed, and the production area is divided, and there should be effective isolation measures between the drainage and irrigation system of the organic plot and the conventional plot to ensure that the water of the conventional plot will not penetrate or flood into the organic plot. Construction of planting, fertilizer, agricultural machinery storage rooms, toilets, garbage, compost treatment and other places, the construction of fireproof belts and drainage channels, leaving sidewalks and mechanical roads. At the same time, the corner plots are used to build natural enemy protection sites to protect biodiversity.

1.3 Administrative Requirements

Management plans should be carried out in strict accordance with the requirements of organic production documents, and crop rotation plans should be formulated to intercropp nitrogen and green manure crops in corner land and vacant plots to improve soil fertility and reduce dependence on off-farm fertilizers. Biodiversity is protected through the use of agricultural, biological, ecological and physical control measures for pest control and disease control. Avoid soil or crop pollution and ecological damage caused by agricultural activities, and control soil erosion. For strict internal quality control, it is necessary to maintain a complete record of the whole process of production management and sales, including the date, source and quantity of all input substances such as seeds (propagating materials), fertilizers, plant protection products purchased; fertilizer application records, including fertilizer application date, application plot, type and quantity of fertilizer applied; plant protection product application records, including application date and reason, product name and quantity, application method; harvest records, including harvest date, variety and quantity of organic (converted) crops. When producers harvest both organic and non-organic products, the date, time, transport route, and date and time of receipt of both organic and non-organic products should be recorded.

2 Fine land preparation

2.1 Land preparation

Before planting, the forest land should be prepared according to local conditions to adapt to planting and mechanized management, and the installation of drip irrigation or sprinkler irrigation facilities and water network pipes should be carried out first, the drainage system should be done, and the water withdrawal should be monitored if possible. In order to prevent soil erosion and soil desertification and salinization, terraces or reclamation belts with a width of 20 to 30 cm should be opened along the contour line of 1.5 to 2.0 cm for planting. At the same time, crop straw should be fully utilized and the burning of straw on the spot should be prohibited.

2.2 Arable land

Grass coral colonization time is generally in November to December and March to April of the following year, before colonization, the inter-row soil under the forest is turned about 40 cm deep, crushed, removed gravel, tree roots, dead branches and weeds, applied bio-organic fertilizer that meets the organic production standards 5 t/hm 2, and then use a rotary tiller to rotate the bio-organic fertilizer into the soil, plough the soil, raise the furrow 20 cm high, and the furrow width is 0.5 to 1.0 m.

3 Transplanting and colonization

3.1 Seedling selection

Organic grass coral seeds or seedlings should be used for cultivation, and in the case of purchase of certified organic grass coral seeds or seedlings, conventional seeds or plant propagation materials with unconstrained substances can be used to cultivate annual grass coral seedlings using organic production. Before planting, select seedlings that are more than one year old, grow strong, seedling height of more than 20 cm, and diameter of more than 0.2 cm, cut off too many branches and leaves, and retain 6 to 8 leaves, so as not to consume too much water and nutrients and lead to low survival rate of seedlings.

3.2 Colonization

Colonization in the evening on cloudy or sunny days, if it cannot be planted in time, it should be planted falsely or placed in a wet place for preservation, and the time from seedlings to planting should not exceed 5 days. Colonize at 20 cm×30 cm row spacing and water through the roots. If it is in the dry and cold season, it should be covered with mulch film for heat preservation and moisturizing. After transplanting, check the seedlings and supplement the seedlings in time, pull out the dead seedlings and the injured and dried seedlings, ensure the whole seedlings, and ensure the yield.

4 Fertilizer water management

4.1 Soil fertilization

Grass corals prefer loose, fertile, humus-rich, acidic soils, and avoid poor, compacted, and watery and sticky soils [6]. After colonization, 15~20 days after colonization, 1 time of fulvic acid organic water-soluble fertilizer 500 times liquid was applied to promote new roots and promote plant growth. The 3rd month was combined with the application of bio-organic fertilizer 3 t/hm2 in combination with medium tillage. Thereafter, every 30 days, apply 500 times of the fulvic acid organic water-soluble fertilizer until harvest. In addition, it is necessary to carry out soil fertilization programs, plant nitrogen-fixing plants such as legumes, and compost based on microbial, animal-derived, and plant-derived materials. The microorganisms used in organic compost composting must come from nature, not genetically engineered products, reduce the application of fertilizer outside the farm, and it should be noted that the nitrogen in the animal manure applied to the farm plot each year should not exceed 170 kg/hm2.

4.2 Moisture management

Grass corals require a large amount of water from the initial flowering stage to the fruit color change period, and should be drip or sprinkler irrigation to keep the soil moist; in the rainy season, it should be drained in time to avoid water rotting roots. Stop watering 7 to 10 d before harvest to prevent late ripening of grass corals.

5 Weeding in medium tillage

In order to maintain loose soil, promote grass coral growth and extract side branches, it is generally necessary to cultivate 1 to 2 times a year. After colonization, interforest management should be strengthened, and the loose soil should be cultivated in the third month after colonization, and the loose soil should be shallow, not hurting the roots, and not pressing the seedlings.

Remove weeds in time, keep the forest ventilated and transparent, and prevent the breeding of pests and diseases. Organically produced grass corals prohibit the use of herbicides, so manual or mechanical weeding is required, and water and fertilizer management and weed suppression can be carried out by drip irrigation and covering anti-weed cloth. Although drip irrigation and cover film have more fixed investment in the early stage, according to calculations, the input of labor costs can be greatly reduced after the second year.

6 Forest management

The closure of trees is the key factor affecting the growth of grass corals and the occurrence of diseases, such as insufficient light, poor ventilation and light transmittance, poor growth of grass corals, high incidence of diseases, and low yields. Therefore, it is necessary to remove too low and dense branches in time to keep the forest canopy between 0.6 and 0.8 to achieve the best economic benefits. In addition, farm manure that has been piled up and fully decomposed can be applied to promote forest growth. Trees must also be managed in strict accordance with organic production.

7 Pest control

Grass corals are more resistant to disease, but poor environments or extreme weather can also lead to diseases. After colonization, pay attention to the occurrence of plexy, when the plant is infected, the base of the stem is yellow-green water stained, and then quickly turns yellow-brown and develops around the stem. The diseased tissue decays, withers and depressions, producing constriction, water stains expanding from bottom to top, and seedlings lodging on the ground. When the air humidity is high, a layer of flocculent white mold can be produced on the diseased body and the surrounding bed soil, causing the leaves, young roots and young stems to turn brown and rot [9]. It can be controlled by spraying Trichoderma Harz, Bacillus subtilis or garlic oil in the early stage of the disease, while keeping the forest ventilated and dry to create a good growth environment.

Grass coral anthrax is a fungal disease, high temperature and high humidity in the spring incidence is more, mainly in the growth leaves, old leaves tip or edge, the spots are close to round, black brown, disease, healthy parts are not obvious. Anthrax is mainly transmitted by wind and rain. In the prevention and control of anthrax, it is possible to clear the garden in the spring, cut off the leaves of diseases and insects, and spray stone sulfur compound to reduce pathogenic bacteria. In the early stage of the disease, some mixed bacterial agents such as Bacillus subtilis can be used to prevent the occurrence of diseases.

Grass coral tail spore leaf spot disease is a fungal disease, the disease is more severe in May to June, the initial disease spots appear a small amount of mold on the back of the leaves, and the later spots become yellow and die. The method of prevention and control is the same as that of anthrax.

If grass corals are exposed to sunlight in the summer, the leaves will burn and the whole leaf will dry up in severe cases. Therefore, it is necessary to use a shade net for shading treatment, while watering for cooling.

When large-scale planting of grass corals under the forest, there is a risk of outbreaks due to the influence of adjacent trees and crops, and the single plant.

When grass corals are plucked, the young buds and leaves are susceptible to aphids. Grass corals that are infested with aphids are susceptible to other diseases in addition to curling leaves and losing their commerciality. In the control of aphids, neem, natural pyrethroids, neem, etc. can be used for control, and at the same time, it is necessary to protect the natural enemies of grass worms, ladybugs and other aphids; it is also possible to use the yellowing of aphids to stick to aphids by hanging yellow plates for physical control.

Snails are prone to snails in the warm and humid environment after rain, which generally harms the young stems and young leaves of grass corals, resulting in gaps in the leaves of grass corals and necrosis. In snail control, copper sulfate + table salt solution or red pepper can be boiled into water and sprayed, or before the peak of snail breeding in May and June, grass and vegetable leaves can be used to induce prevention and control; and ducks can also be stocked to eliminate snails.

Leafhoppers mainly suck on the young stems and young leaves of grass corals, which are the most harmful in July and August, resulting in malnutrition of grass coral leaves, premature leaf fall, and inability to differentiate flower buds. The control methods mainly include physical methods such as hanging yellow plates and frequency vibration insecticidal lamps, and at the same time, weeding, cutting dead branches and egg-laying branches, and clearing the garden in time to eliminate the source of insects. Natural enemies such as spiders, red-eyed bees, bugs, ladybugs, and praying mantises can also be used for control.

Leafminer moth, also known as ghost drawing symbol and drawing insect, belongs to the lepidoptera pest, mainly for the leaves of grass corals, its larvae sneak under the epidermis to feed, leaving many twists and turns, making the leaves curled, seriously affecting the photosynthesis of the leaves and the commerciality of grass corals. It begins to be hazardous in early June and remains in danger until early November. The control methods are similar to those of leafhoppers, mainly based on physical control, biological control and agricultural control.

8 Harvesting

May and October are the optimal harvest periods for grass corals, which should be harvested in May if used as an anti-inflammatory drug and in October if used as an anti-cancer drug. When harvesting, the whole grass coral is cut from 5 to 10 cm above the ground, and then the fresh product is sold directly to the drug dealer. After harvesting, the garden was cleared in time, the diseased plants, dead plants, dead branches, etc. were removed, and the bio-organic fertilizer 5 t/hm 2 was applied in combination with the middle cultivation to promote the timely extraction of the second stubble grass coral.