44 results about "Long term growth" patented technology

Stem cells, including mammalian, and particularly primate primordial stem cells (pPSCs) such as human embryonic stem cells (hESCs), hold great promise for restoring cell, tissue, and organ function. However, cultivation of stem cells, particularly undifferentiated hESCs, in serum-free, feeder-free, and conditioned-medium-free conditions remains crucial for large-scale, uniform production of pluripotent cells for cell-based therapies, as well as for controlling conditions for efficiently directing their lineage-specific differentiation. This instant invention is based on the discovery of the formulation of minimal essential components necessary for maintaining the long-term growth of pPSCs, particularly undifferentiated hESCs. Basic fibroblast growth factor (bFGF), insulin, ascorbic acid, and laminin were identified to be both sufficient and necessary for maintaining hESCs in a healthy self-renewing undifferentiated state capable of both prolonged propagation and then directed differentiation. Having discerned these minimal molecular requirements, conditions that would permit the substitution of poorly-characterized and unspecified biological additives and substrates were derived and optimized with entirely defined constituents, providing a “biologics”-free (i.e., animal-, feeder-, serum-, and conditioned-medium-free) system for the efficient long-term cultivation of pPSCs, particularly pluripotent hESCs. Such culture systems allow the derivation and large-scale production of stem cells such as pPSCs, particularly pluripotent hESCs, in optimal yet well-defined biologics-free culture conditions from which they can be efficiently directed towards a lineage-specific differentiated fate in vitro, and thus are important, for instance, in connection with clinical applications based on stem cell therapy and in drug discovery processes.

Stem cells, including mammalian, and particularly primate primordial stem cells (pPSCs) such as human embryonic stem cells (hESCs), hold great promise for restoring cell, tissue, and organ function. However, cultivation of stem cells, particularly undifferentiated hESCs, in serum-free, feeder-free, and conditioned-medium-free conditions remains crucial for large-scale, uniform production of pluripotent cells for cell-based therapies, as well as for controlling conditions for efficiently directing their lineage-specific differentiation. This instant invention is based on the discovery of the formulation of minimal essential components necessary for maintaining the long-term growth of pPSCs, particularly undifferentiated hESCs. Basic fibroblast growth factor (bFGF), insulin, ascorbic acid, and laminin were identified to be both sufficient and necessary for maintaining hESCs in a healthy self-renewing undifferentiated state capable of both prolonged propagation and then directed differentiation. Having discerned these minimal molecular requirements, conditions that would permit the substitution of poorly-characterized and unspecified biological additives and substrates were derived and optimized with entirely defined constituents, providing a “biologics”-free (i.e., animal-, feeder-, serum-, and conditioned-medium-free) system for the efficient long-term cultivation of pPSCs, particularly pluripotent hESCs. Such culture systems allow the derivation and large-scale production of stem cells such as pPSCs, particularly pluripotent hESCs, in optimal yet well-defined biologics-free culture conditions from which they can be efficiently directed towards a lineage-specific differentiated fate in vitro, and thus are important, for instance, in connection with clinical applications based on stem cell therapy and in drug discovery processes.

Provided are a system and methods for selectively inducing expansion of a population of T cells in the absence of exogenous growth factors, such as lymphokines, and accessory cells for research purposes. The cell based expansion system and methods permit the long-term growth of CTLs, preferably human CTLs. In addition, T cell proliferation can be induced without the need for antigen, thus providing an expanded T cell population that is polyclonal with respect to antigen reactivity. Further provided are methods for using the system and methods to screen and identify antigens related to specific diseases or conditions, tumors, autoimmune disorders, or an infectious disease or pathogen, and to identify target molecule for research purposes, or for developing a vaccine based thereon.

Provided are a system and methods for selectively inducing expansion of a population of T cells in the absence of exogenous growth factors, such as lymphokines, and accessory cells for research purposes. The cell based expansion system and methods permit the long-term growth of CTLs, preferably human CTLs. In addition, T cell proliferation can be induced without the need for antigen, thus providing an expanded T cell population that is polyclonal with respect to antigen reactivity. Further provided are methods for using the system and methods to screen and identify antigens related to specific diseases or conditions, tumors, autoimmune disorders, or an infectious disease or pathogen, and to identify target molecule for research purposes, or for developing a vaccine based thereon.

The invention discloses a rapid ecological restoration method for rock-soil side slopes, and relates to the field of ecological management for the rock-soil side slopes. The rapid ecological restoration method includes: (1) cleaning a rock-soil side slope; (2) paving a high-tensile net; (3) preparing basic materials for vegetation growth; (4) allocating vegetation, mixedly planting seeds and grass blades of shrubs and herbage plants endurable to draught and infertility and selecting rock-soil side slope protective Bermuda grass blades; (5) subjecting the vegetation to spray-planting; and (6) maintaining and managing. Since the rock-soil side slope protective Bermuda grass blades are selected to protect the rock-soil side slopes, the rapid ecological restoration method is efficient and rapid; the basic materials for the vegetation growth are easy to obtain, simple to prepare, scientific to prepare, capable of effectively meeting requirements on nutrient and moisture of the vegetation, beneficial to flourishing and long-term growth of the vegetation and the like; and the herbage plants and the shrubs endurable to draught and infertility are selected as the vegetation to be planted mixedly, so that the rapid ecological restoration method is good in landscape allocation effect. The rapid ecological restoration method is applicable to ecological restoration in earth-rock mountain regions, and is particularly beneficial to stability of eco-fragile regions with bare rocks.

The invention discloses a method for greening and restoring a hard side slope. The method comprises the steps of cleaning a slope surface, arranging an anchor rod, laying a galvanized wire mesh sheet,improving red sandstone into planting soil, laying a geomembrane, executing sowing, establishing an automatic irrigation system and executing operation and maintenance, wherein the red sandstone soillayers with different sandstone contents are improved by adding an improver, meanwhile spray heads are installed on a pre-buried spray system by utilizing an automatic control system, and planted plants are irrigated by using the spray heads. A sprinkling irrigation system can be automatically controlled according to temperature and humidity. The invention provides a hard slope greening restoration technology for improving red sandstone into planting soil. Long-term growth conditions are provided for vegetations, the ecological restoration requirements of a rock slope and a hard slope are met, slope protection greening planting plants are combined with a traditional vegetation concrete ecological-restoration technology, vegetation restoration and anchoring fixation are simultaneously carried out, and the vegetation growth on slopes and slope fixation can be better achieved.

Provided are a system and methods for selectively inducing expansion of a population of T cells in the absence of exogenous growth factors, such as lymphokines, and accessory cells for research purposes. The cell based expansion system and methods permit the long-term growth of CTLs, preferably human CTLs. In addition, T cell proliferation can be induced without the need for antigen, thus providing an expanded T cell population that is polyclonal with respect to antigen reactivity. Further provided are methods for using the system and methods to screen and identify antigens related to specific diseases or conditions, tumors, autoimmune disorders, or an infectious disease or pathogen, and to identify target molecule for research purposes, or for developing a vaccine based thereon.

Undifferentiated primordial stem cells are manipulated to permit their long term growth in defined media lacking serum and feeder layer cells by shifting the apoptotic balance of the cells, through increasing the activity of Bcl-2 family anti-apoptotic proteins or decreasing the activity of Bcl-2 family pro-apoptotic proteins. In some embodiments of the invention, the Bcl family protein is Bcl-2. The ES cells sustain the characteristics of undifferentiated, pluripotent stem cells during long-term serum- and feeder layer cell-free conditions, including the ability to be expanded in vitro, but maintain their potential to differentiate into mature cell types.

The invention discloses a three-dimensional greening structure for a bridge pier. The three-dimensional greening structure comprises a bottom sleeve surrounding the upper surface of the bridge pier and a plant cultivating sleeve; the three-dimensional greening structure is characterized in that a worm driven by a motor I to rotate, and a slide chute are arranged in the bottom sleeve; a rotary sleeve connected with the plant cultivating sleeve into a whole is arranged in the slide chute; a turbine meshed with the worm is arranged at the bottom of the rotary sleeve; idler wheels are arranged at the bottom of the rotary sleeve and clung to the slide chute; and a three-dimensional support structure is arranged on the plant cultivating sleeve and comprises a hinge seat fixed on the plant cultivating sleeve. The three-dimensional greening structure has the beneficial effects that greening plants of the bridge pier can be trimmed up and down through a reasonable structure design, growing plants can be horizontally trunked and trimmed, meanwhile, in order to prevent the plants from winding the bridge pier, the plants can be driven to rotate as a whole and the plants are prevented from winding the bridge pier during long-term growth, and manpower can be saved through mechanized maintenance, so that the three-dimensional greening structure is suitable for promotion and use.

The present invention relates to pluripotent stem cells and methods of promoting long term growth of such cells. In particular, the methods described are used to enhance the proliferation of hematopoietic stem cells, hematopoietic precursor cells, hemangioblasts and endothelial stem cells. The present invention also relates to methods of using such cells, comprising introducing such stem cells, into the host. The present invention also relates to pharmaceutical compositions comprising the cells and such compositions may include growth factors or cytokines to allow for further cell growth and / or cellular differentiation. The invention further relates to methods of in vivo administration of a protein or gene of interest comprising transfecting the stem cells grown by the methods described, with a construct comprising DNA which encodes a protein of interest and then introducing the stem cell into the host where the protein or gene of interest is expressed.

The invention discloses an ecological slope protection structure for a high and steep spray-sowing side slope in an arid area and a construction method of the ecological slope protection structure. The ecological slope protection structure can meet the long-term growth requirements of plants. The ecological slope protection structure for the high and steep spray-sowing side slope in the arid area comprises a concrete slope and a reinforcing mesh, and further comprises at least two rows of vegetation recovery mechanisms which are arranged in a spaced mode in the inclination direction of the slope surface of the high and steep side slope. Each row of vegetation recovery mechanism comprises at least two vegetation recovery grooves which are formed in a spaced mode. Each vegetation recovery groove comprises a recovery groove enclosing wall, a concrete layer arranged on the bottom surface of the vegetation recovery groove, and an anti-seepage paint layer arranged on the concrete layer. A sand gravel under layer, a planting soil layer and a covering layer are sequentially arranged in each vegetation recovery groove from bottom to top. The ecological slope protection structure is a novel slope protection structure which integrates a spray-sowing slope protection structure and the vegetation recovery mechanisms, the planting soil layers communicate with water and soil matrixes located in the high and steep side slope and used for plant growth and have the good water-retaining property, and the requirement for the water and soil matrixes for long-term growth of plants in the arid area is met.

The invention discloses a plane root-zone irrigation method and an irrigation device. The irrigation device sequentially comprises a base layer with bearing capacity, an intermedium material arranged above the base layer, and a soil or plant container arranged above the intermedium material and connected or attached to the intermedium material, wherein, the intermedium material can be a membrane material, a coiled material, a sheet material or a plate material which take a spongy, lacunose or fibrous shape and has a function of absorbing and storing a liquid. The invention has the following beneficial effects: 1. water and nutrients are uniformly supplied to a plant, thus ensuring long-term growth of the plant; 2. construction is very simple, convenient and fast: a framework does not need to be built outside structures such as a greened wall surface and the like, as the base layer or a base material can bear the weight of all objects added thereon by means of the strength thereof, and a large number of drip irrigation heads do not need to be mounted; 3. the irrigation device is combined with a waterproof membrane to achieve simple structural levels, wherein, the thickness from a waterproof layer to a plant layer does not exceed 10cm, thus eliminating hidden danger of water leakage and avoiding a plant root penetrating through a wall; and 4. construction cost and maintenance cost are low, thus providing guarantee for wide popularization.

The invention provides a high-steep hard slope greening system and an application method thereof. The high-steep hard slope greening system comprises a plurality of holes formed in a hard slope surface. Ecological cylinders are arranged in the holes. Each ecological cylinder is filled with an ecological medium for planting plants. A spray-irrigation water supply system is arranged on the upper side of the slope surface. A water intercepting ditch is formed in the bottom of the slope surface. The spray-irrigation water supply system supplies water and waters the plants in the ecological cylinders. The water intercepting ditch is used for drainage of the greening system. Ecological repairing and greening are conducted on the hard slope through the multi-layer porous ecological cylinders, the advantages of a vegetation base material and the porous ecological cylinders are sufficiently used, by locally forming pores in the slope surface and placing the slope protection ecological cylinders, the long-term growth conditions are provided for vegetations, and the ecological repairing requirement of the rocky slope surface and hard slope surface is met. The disturbance of the slope protection ecological cylinders on the slope surface is small, meanwhile the potential adverse effects of the vegetation long-term growth requirement and the plant root system on the slope surface are considered, and the high-steep hard slope greening landscape can be effectively kept.

The invention discloses a method for ecological remediation of a side slope. According to the method, a reasonable material proportion of a spraying-seeding substrate is summarized on the basis of a lot of test data and project experience, so that the physicochemical properties of the substrate reach the best indexes required for the growth of plants; compared with highly-dispersive soil particlesformed by technologies of the same kind, the soil structure with rich pores is formed by means of the method, can achieve water retention and ventilation, slow down leaching loss of nutrient elements, and guarantee the good growth of root systems of the plants; sprayed artificial soil is small in density, low in unit weight, and large in internal friction angle, is easily attached to a steep slope, and is unlikely to be peeled off; compared with the technologies of the same kind, the spraying-seeding thickness can be obviously increased, and the long-term growth demands of the plants are met.Through the use of polyacrylamide, the effect of flocculating the solid substrate is achieved, so that the substrate sprayed on the slope surface is subjected to solid-liquid separation, clear wateris filtered out, and the loss of the solid substrate and nutrients is reduced; in the dewatering shrinkage process of the substrate, the solid substrate forms a granular structure with certain porosity, and thus the growth of the plants is better facilitated.

The invention belongs to the technical field of land reclamation, and concretely discloses a scientific fertilizing method of Neyraudia reynaudiana. An organic and inorganic combination fertilizing technology is adopted based on a sustained and controlled release fertilizing principle and the physiologic characteristics of a fertilizer according to the characteristics of destroyed land soil and the seedling stage fertilizer demanding characteristics of Neyraudia reynaudiana in production construction activity, so the physical and chemical properties of soil can be reconstructed, the root growth and the plant tillering of Neyraudia reynaudiana can be promoted, seedlings can be cultivated and strengthened, and the fertilizer utilization rate and the fertilizer efficiency release speed can be improved. The method is in favor of realizing a fertilizer long-term effect, realizes soil improvement and fertilizer increase, and promotes the long-term growth of Neyraudia reynaudiana.

Undifferentiated primordial stem cells are manipulated to permit their long term growth in defined media lacking serum and feeder layer cells by shifting the apoptotic balance of the cells, through increasing the activity of Bcl-2 family anti-apoptotic proteins or decreasing the activity of Bcl-2 family pro-apoptotic proteins. In some embodiments of the invention, the Bcl family protein is Bcl-2. The ES cells sustain the characteristics of undifferentiated, pluripotent stem cells during long-term serum- and feeder layer cell-free conditions, including the ability to be expanded in vitro, but maintain their potential to differentiate into mature cell types.

The invention provides a special fertilizer for bletilla striata. The special fertilizer comprises the following raw materials: a chemical fertilizer and an organic fertilizer. At first, the contents of organic matter and nitrogen phosphorus and potassium of the special fertilizer for bletilla striata are controlled, so that planted bletilla striata can fully but not excessively absorb all nutritional ingredients; the release amounts of nitrogen phosphorus and potassium are controlled through a urea formaldehyde controlled-release fertilizer and a compound containing a radical as shown in the description, so that the demands on nutritional elements for long-term growth of bletilla striata are guaranteed; moreover, due to the selection of raw materials of the organic fertilizer and bacteria species, the root system of Bletilla Striata (Thunb.) Reichb.f. can be promoted to absorb the nutritional elements; through the unique technological design, acid-basic microbes of the fertilizers are subjected to fermentation treatment; through the adoption of the special fertilizer, seedling burning is prevented, and the yield is improved by 30% or above.

The invention discloses a planting method capable of improving survival rate of jatropha curcas L., and belongs to the technical field of planting. The method includes the following steps of soil preparation, seedling cultivation, seedling plating and the like. According to the method, treatment measures of digging planting holes, applying 0.5-1.5 kg of chicken manure in the planting holes and the like are adopted, the volume of the planting holes are increased, and the acid-base property of the planting holes is improved, so that the volume and the acid-base property of the planting holes are suitable for the long-term growth of the jatropha curcas L.; meanwhile, disinfection treatment and rooting promoting treatment are conducted on the seedlings of the jatropha curcas L., so that the survival rate of the seedlings of the jatropha curcas L. is relatively high after transplantation, and the rooting and growth of the seedlings of the jatropha curcas L. are well promoted; during the planting period, scientific fertilization is conducted to make the trees of jatropha curcas L. grow vigorously, so that the yield of fruits is promoted, the yield of fruits is still relatively high many years after the planting, and the method is suitable for massive planting.

Cell culture media formulations for culturing human epithelial cells are herein described. Also described are methods of increasing population doublings in a cell culture of finite life span human epithelial cells and prolonging the life span of human cell cultures. Using the cell culture media disclosed alone and in combination with addition to the cell culture of a compound associated with anti-stress activity achieves extended growth of pre-stasis cells and increased population doublings and life span in human epithelial cell cultures.

The invention discloses a nutrient soil for green garden flower cultivation and a preparation method thereof. The nutrient soil for green garden flower cultivation is prepared from the following raw materials in parts by weight: 25 to 35 parts of amino acid, 20 to 25 parts of dregs of decoctions,11 to 18 parts of vitamin B6, 6 to 11 parts of calcium nitrate terahydrate, 10 to 15 parts of humus, 8 to 15 parts of EDTA chelated zinc, 11 to 22 parts of feeding maggots, 6 to 12 parts of potassium ferrate, 8 to 11 parts of red brick clasts, 1 to 3 parts of bacillus subtilis, 3 to 5 parts of plant ashes, 4 to 9 parts of watermelon juices and 10 to 20 parts of sodium naphthalene-1-acetate. The nutritive soil has the functions of helping the garden cultivated plants to absorb the nutrient elements in various growth stages evenly, increasing the plant nutrition, promoting the plant growth, improving the plant resistance and resisting the plant disease; coordinating the humus with the plant ashes can improve the fertilizer efficiency duration, while long-term growth of flower is well maintained, light nutrient substrate raw materials of the EDTA chelated zinc, the potassium ferrate, the red brick clasts and the like are used, the transportation cost of the substrate is significantly reduced, and the nutrient soil is suitable for greening of the garden flowers due to the long-term and light characteristics.

The present invention relates to the data analysis technology field, especially to a residential electricity consumption prediction method based on a time series model. The method comprises the following steps: performing analysis modeling through historical data, fully employing electricity consumption data over the years, considering seasonal fluctuation and temperature influence in the condition of long-term growth trend, and predicting electricity consumption through the time series model. The residential electricity consumption prediction method based on the time series model assists a program construction department and a finance department in performing power network program construction and financial budget management to perform prediction of future electricity consumption. The time series model is employed to perform residential electricity consumption prediction according to data such as resident user growth trend condition and the resident electricity consumption over the years and on a quarterly and year basis.

The invention discloses a cultivating method of tomato trees and aims to realize the long-term growth and disease resistance and high yield of the tomatoes. The method comprises the following steps: disinfection of nutrient soil, cultivation of root stock seedlings, cultivation of scion seedlings of mini-tomatoes and colored tomatoes, grafting, grafted seedling management, field planting to field or greenhouse flowerpots, and shaping, trimming and pruning. Compared with existing tomato cultivation techniques, the cultivating method provided by the invention changes the tomatoes into woody plants and realizes the purposes of cultivating once, growing for many years and rapid growing. The plants can grow to a height of 4-5m in a quarter and the side branches can also be used as the basic branches. The method can completely change the traditional single trunk pruning method, and the number of buds can be increased by 40-60, and a plant has 3-4 trunks. The plants can grow through a summer or a quarter when cultivated in an open field and can bear fruit throughout the year when cultivated in greenhouses. The method can increase the yield by 3-4 times, realizing a yield of 15,000-20,000 kg per mu, and increase the nutrient content by 2-3 times. The varieties have high immunity against the soil infectious disease and cropping cultivation can be achieved.

The invention discloses a plant culture medium formula and a manufacturing method thereof, wherein the plant culture medium formula comprises peats from Northeast of China, fine pine tree barks, rice chaffs and fermented cow dung; and the components by weight percent comprises: 30-60% of the peats from Northeast of China, 10-25% of the fine pine tree barks, 10-30% of the rice chaff and 10-20% of the fermented cow dung; after the components are blended and packed separately, the product is acquired. According to the plant culture medium formula and the manufacturing method thereof provided herein, the plant culture medium is suitable for viaduct greening planting; light amount of nutrient medium is adopted as material, so the plant culture medium can retain water, fertilizer, slowly release and provide necessary growing ingredients for plants; the organic matter and the micro elements are rich, thus the fertilizer effect is durable; and insects and pests do not easily occur, thus the long-term growth of the plant can be better maintained.

The invention discloses an edible mushroom cultivation base material and relates to the technical field of edible mushroom cultivation. In order to solve the technical problems that the existing cultivation base materials are prepared from perishable raw materials such as wood chips, wheat bran and straws, the raw materials easily deform, shrink and even sink after rotting, and are adverse to long-term growth of an edible mushroom, and since a nutrient solution cannot be absorbed sufficiently due to shrinkage, the quick growth of the edible mushroom is influence, the base material mainly takes bamboo powder as a raw material of the cultivation base material to utilize the characteristics of specific corrosion resistance, good bacterium resistance, good bacterium inhibition capability and good moisture absorption capability of a bamboo fiber; appropriate sawdust and a common auxiliary material are in combination; the characteristics that too quick rotting is avoided in an edible mushroom culture process, particularly a bagged cultivation process, a fertilizer effect is kept continuously for a long term, and non-deformation is avoided can be guaranteed; and the cultivation efficiency of the edible mushroom is effectively improved.

The invention discloses an artificial intelligence-based accurate teaching and research method. The method comprises the following steps: firstly, obtaining a classroom video after a certain course isfinished through an audio and video acquisition device; generating a classroom observation report according to the obtained classroom video; based on the classroom participation degree curve, callingtime points of rising and lowering of the participation degree, and then calling videos near the corresponding time points to obtain a condition that the participation degree is changed due to the fact that teachers and students perform specific teaching activities; according to the two paths of videos of the teacher and the student in class, the questioning frequency and the questioning type ofthe teacher in class are obtained, and the characteristics of the teacher in class in the class question design are obtained; and generating a teacher teaching evaluation scale according to the obtained classroom observation report and the characteristics of the problem design, and generating a teacher ability matrix based on the contents in the teaching evaluation scale. According to the method,the classroom course evaluation report can be presented to teachers in a more scientific, convenient and rapid teaching and research mode, the course evaluation workload of the teachers is reduced, and suggestions are provided for the long-term growth direction of the teachers.

The invention discloses a production method of a suaeda salsa pudding and relates to a pudding. The invention aims at the defects of high sugar and high cholesterol in the existing pudding products and provides the suaeda salsa pudding with low sugar and low cholesterol. Suaeda salsa is sweet in taste and cold in property, is capable clearing away heat and toxic material and reducing blood pressure and blood fat, especially has a weight-reducing effect, is a main traditional Chinese medicine for treating hepatitis, is capable of reducing cholesterol and blood fat and has good curative effectson hypertension and diabetes. Biologic iodine and beta carotene in the suaeda salsa are two of important components essential for long-term growth for infants provided by breast milk.

The invention relates to a Chinese medicine material planting method, namely a culture method for long-neck American ginseng. The steps are as the follows: (1) selection of a growing environment and growing conditions, (2) a direct seeding, non-transplanting and anti-grain-running-down method, (3) management for increasing growth of a ginseng neck, (4) light-degree management and reduction of human intervention, and (5) a method for prolonging a picking period and protecting and collecting a stem basal part. To grow into a long neck, the stem basal part must uptake a special culture method under long-time growing effect, and therefore the long neck formed through long term growth and the features of wild ginseng characterized by high quality of effective components calculated in a long term are favored and admired by consumers. The culture method for the long-neck American ginseng provides a production method integrating the advantages of both a production method for cultivating the wild American ginseng and a production method for cultivating the American ginseng, achieves combined creation, and effectively makes up for the shortcomings of supplying of a wild American ginseng product.

The invention relates to the technical field of culture substrates, and relates to a culture substrate based on peat sawdust. Raw materials of the culture substrate comprise peat sawdust, coconut chaff and fermented unlined upper garment wood chaff, wherein the quality of the peat sawdust accounts for 40-55% of the total mass of the culture substrate; the quality of the coconut chaff accounts for20-40% of the total mass of the culture substrate; the quality of the fermented unlined upper garment wood chaff accounts for 5-40% of the total mass of the culture substrate; the particle size of theculture substrate is not more than 30mm; and the pH value is 5-7.2. The culture substrate has comprehensive nutrition, and is rich in nitrogen, phosphorus, potassium, organic matter and humic acid, has long-lasting fertilizers, so that the nutrient requirements of long-term growth and development of plants can be met; and the culture substrate has good physical properties, good permeability and structure, proper water-air ratio, decomposition resistance and good physical structure stability, so that the defects of poor air permeability and uneven nutrients of the existing culture matrix can be effectively solved, and the aims of enhancing the air permeability of the culture substrate and fully and uniformly supplying nutrients can be achieved.

The invention provides a plant growth ring for preventing loose fine granular nutrition substances from falling out. A cavity (2) is processed in a circular ring of the plant growth ring (1), a plant nutrition medium (3) with the loose fine granular nutrition substances is contained in the cavity, air holes (4) are processed in the outer circular wall of the upper half part of the circular ring, a meshed material (5) attaches to the surface of the inner wall of the outer circular wall of the upper half part of the circular ring, edge parts (6) of a plurality of meshed holes of the meshed material cross the air holes, the pore space of each meshed hole is less than that of each air hole, and the meshed material is an elastic material such as a plastic material. According to the plant growth ring, the meshed material attaches to the surface of the inner wall of the outer circular wall of the upper half part of the circular ring, and the edge parts (6) of the plurality of meshed holes of the meshed material cross the air holes, so that the loose fine nutrient substances are prevented from falling out through the air holes, the influences on the long-term growth of plants in the plant growth ring and on the appearance tidiness and beauty of the plant growth ring are avoided, and a wearer with the fashionable decorated ring is free of embarrassment. Therefore, the plant growth ring is worthy of popularization.

The invention discloses a method for planting selenium-enriched rice, comprising the following steps: (1) pretreatment of rice fields; (2) transplanting of rice seedlings; (3) fertilization at tillering; (4) stocking of ducks; (5) fertilization at full heading; and (6) harvesting. The broad bean selected in the present invention is a green manure which can be combined with a nitrogen-fixing bacteria to increase the nitrogen content of the soil, and provide fertilizer for the long-term growth of the rice seedling; the turning over of green manure and retting before the transplanting further increase the soil fertility and the balance of the elements, so that the rice seedlings are balanced; and the organic selenium fertilizer is sprayed during the process of broad bean cultivation so as toincrease the selenium content of the broad bean, the organic selenium content in the soil is greatly increased after turning over of green manure and retting, and the absorption of organic selenium inrice is increased, which greatly increases the selenium content in rice. The method increases the selenium content of rice by increasing the interaction between increase in soil organic selenium content and spraying of organic selenium fertilizer.