84results about How to "Lower hatch rate" patented technology

The invention relates to a parent fish breeding and hatching method for greenlings, belonging to the technical field of fish breeding and hatching. The parent fish breeding and hatching method for greenlings is characterized by comprising the following factors of parent fish selecting time and standard, breeding pond and stocking density, water temperature control, bait feeding, illumination control, egg taking for insemination, and hatch. In the parent fish breeding and hatching method for greenlings, grown maturity-approaching parent fish is enabled to be mature in advance by adopting the breeding measures of manually controlling temperature and light, adjusting bait and water quality, and the like; the parent fish bred by the method can be mature for 15 to 20 days earlier than that in a natural sea area; the mature rate of the parent fish reaches more than 70 percent, and the hatching rate of eggs reaches 85-90 percent, which are shown in the figure II (hatch-approaching eyed eggs); and in the clustered hatched egg blocks, a plurality of eggs are yellowed and are dead, and the hatching rate is low (shown in the figure III). By being used for manual breeding, the method is favorable for protecting natural resources, reducing energy consumption caused by heating during breeding, and changing the shapes of the egg blocks so as to increases the water contact area of the egg blocks and improve the hatching condition and the hatching rate.

The invention discloses the siRNA of SjLGL gene of schistosoma japonica. The siRNA may be one pair or any more than two pairs of nucleotide sequences represented by SEQ ID No.1 and SEQ ID No.2, nucleotide sequences represented by SEQ ID No.3 and SEQ ID No.4, and nucleotide sequences represented by SEQ ID No.5 and SEQ ID No.6. The invention also discloses the use of the siRNA of the SjLGL gene of schistosoma japonica. The siRNA of the SjLGL gene of schistosoma japonica can obviously inhibit the transcription of the SjLGL gene, obviously lower the hatchability of the eggs of insects in livers of mice infected with schistosomes and is suitable for preparing medicines for treating schistosomiasis.

The invention discloses a method for pruning a tea tree. After spring tea is picked every year, a tree crown of the tea tree which is more than 30 to 60 centimeters away from the ground is pruned completely by using a tea tree pruning machine in a horizontal pruning method from May 2nd to 15th. Due to the adoption of the pruning mode, exuberant branches with small physiological ages can be promoted to be sprouted from the tea tree, and large and full buds can be obtained in the following spring to meet the requirement on early time and quality of famous and high-quality single-bud tea. In addition, the method has certain effects on the prevention and control of plant diseases and insect pests of tea gardens and the improvement of the utilization rate of fertilizer water and the picking efficiency of the tea gardens.

The invention provides a genetic control method for tea geometrids, and belongs to the technical field of tea geometrid control methods. The genetic control method for the tea geometrids comprises the following steps of (1) controlling A population of tea geometrids in the northern area of the Zhejiang province, the southern area of the Jiangsu province and the eastern area of the Anhui province and B population of tea geometrids in the other areas of the China; (2) forecasting the occurrence quantity and the emergence period of the tea geometrids in the controlled areas; (3) collecting and feeding the population of the controlled tea geometrids; (4) releasing of pupas or imagoes: releasing male pupas or male moths in the B population into the A population according to the proportion of the sum of the A population: the sum of the B population=1:0.5-1.5 when the B population is used for controlling the A population; and releasing male pupas or male moths in the A population into the B population according to the proportion of the sum of the B population: the sum of the A population=1:0.5-1 when the A population is used for controlling the B population. Injurious insects are regulated and controlled by mutual interference of different geographical populations; the genetic control method is a green control method; and the problem of pesticide residue can be solved, so that the safety on tea leaves can be improved.

The invention relates to a nano material copolymerization mineral substance, a plant extract insecticidal bactericide and a preparation method thereof. The bactericide comprises mineral soil, a composite nano photocatalytic material and a plant extract; the composite nano photocatalytic material and the plant extract are jointly immobilized on the mineral soil. According to the plant extract insecticidal bactericide o the invention, the composite nano photocatalytic material and the plant extract are jointly immobilized on the mineral soil through a specific method; and the realization of thestandardized production of the insecticidal bactericide can be realized; just a small dosage of the insecticidal bactericide needs to be used; the insecticidal bactericide can exert its effects fast;the insecticidal bactericide just needs to be sprayed a few times; the insecticidal bactericide is stable and is not influenced by territorial environment; the efficiency of the insecticidal bactericide is not reduced at night; the insecticidal bactericide has a cost advantage; the insecticidal bactericide is non-toxic and environmentally friendly; and the insecticidal bactericide is a water-basedor aqueous dispersion and can be prepared into powder or aqueous dispersion.

The invention discloses siRNA of schistosoma japonicum SjELAV-like 2 genes. The siRNA is selected from one pair of a combination of more than optional two pairs as follows: nucleotide sequences shownas SEQ ID NO.1 and SEQ ID NO.2, nucleotide sequences shown as SEQ ID NO.3 and SEQ ID NO.4, and nucleotide sequences shown as SEQ ID NO.5 and SEQ ID NO.6. The invention further discloses the application of the siRNA of schistosoma japonicum SjELAV-like 2 genes. The siRNA of schistosoma japonicum SjELAV-like 2 genes disclosed by the invention is capable of obviously inhibiting transcription of the schistosoma japonicum SjELAV-like 2 genes and obviously reducing the liver egg hatching rate of schistosomiasis infected mice, and is applicable to preparation of drugs for treating schistosomiasis.

The invention provides a composition and feed for feeding coccinella septempunctata, and a preparation method of the composition. The composition comprises the following components in parts by weight: 500-1000 parts of aphid treatment substances, 1-4 parts of [beta] carotene, 0.000001-0.00001 part of juvenile hormone and the like. The feed composition provided by the invention comprises the aphid treatment substance, the juvenile hormone and the [beta] carotene, wherein the aphid treatment substance has relatively comprehensive basic nutrients, the juvenile hormone has the characteristic of promoting ovarian development of adults, and the [beta] carotene has the characteristics of improving the survival rate of insects and protecting follicles and uterine cells. The egg laying amount and the hatching rate of the coccinella septempunctata fed by the composition have no significant difference from the egg laying amount and the hatching rate of the coccinella septempunctata fed by conventional bean aphids, and the feed is favorable to be stored and is conveniently used. The whole demand quantity of aphids can be reduced by about 20%, the space is saved by 50% or above, and the labor demand is reduced by 30% or above.

The invention discloses a poultry egg windowing and sealing method. The invention comprises the steps: windowing on a poultry egg equatorial plate position, keeping a full eggshell membrane, forming a concentric sealing ring on the eggshell by using hot melt adhesive or the like, taking a window center as a circle center, dropwise adding physiological buffer solution after the concentric sealing ring and the eggshell surface are bonded firmly, removing the eggshell membrane under the buffer solution blockage condition, positioning an embryo and performing the embryo operation, then fully covering the window under the solution by using the prepared eggshell membrane, absorbing surplus solution in the sealing ring by using absorbent paper, then filling the interior of the sealing ring by using the hot melt adhesive or gelatin. The poultry egg windowing and sealing method effectively increases transgenic poultry egg hatching rate and transgenic efficiency by optimizing an operation proposal.

The invention relates to a laneway type incubator with independent left and right laneway temperature control, which comprises a box board, an air door box, an incubation vehicle, a temperature probe,temperature control probes, a wetting spray nozzle, water cooling components, heating components, a fan component, a right laneway, a left laneway and an intelligent temperature adjusting probe, andis characterized in that: two sets of the heating components, the water cooling components and the temperature control probes are provided; and the left laneway and the right laneway are symmetricallyarranged. The laneway type incubator reduces the temperature difference between the left laneway and the right laneway, greatly improves the production performance, meets the requirements of the leftand right laneways for incubating different quantities of breeding eggs or different breeding eggs and maintains incubation efficiency.

The invention discloses siRNA of a schistosoma japonicum katsurada SjFrzb2 gene. The siRNA has nucleotide sequences as shown in SEQ ID NO. 1 and SEQ ID NO. 2. The invention also discloses an application of the siRNA of the schistosoma japonicum SjFrzb2 gene. The siRNA of a schistosoma japonicum SjFrzb2 gene can obviously inhibit the transcription of the SjFrzb2 gene, the insect body number of schistosomiasis infected mice, the number of liver eggs, the liver egg contribution rate and the egg hatching rate of each female insect can be remarkably reduced, a certain pathological influence is alsocaused to the integument structure of the insect and the cell morphology of the gonad, and the product is suitable for being prepared into drugs for preventing and treating schistosomiasis.

The invention discloses siRNA of a schistosoma japonicum SjLwr gene. The siRNA has nucleotide sequences as shown in SEQ ID NO.1 and SEQ ID NO.2; or nucleotide sequences shown in SEQ ID NO.3 and SEQ IDNO.4, or nucleotide sequences shown in SEQ ID NO. 5 and SEQ ID NO. 6. The invention also discloses an application of the siRNA of the schistosoma japonicum SjLwr gene. The siRNA of the schistosoma japonicum katsurada SjLwr gene can obviously inhibit transcription of SjLwr gene, can obviously reduce schistosome infected mouse insect body number, liver egg number, and liver egg contribution rate and egg hatching rate of each female insect, has certain pathological influence on insect integument structure and gonad cell morphology, and is suitable for preparation of drugs for prevention and treatment of schistosomiasis.

The invention relates to the technical field of fry hatching, in particular to a tilapia mossambica roe hatching circulation system. The system comprises a rack, a hatching pond, a temporary raising pond, a fry pond, hatching barrels, a temporary raising basin, a water storage pond and a water supply pond. By forming a hatching cavity, each hatching barrel can be cultured independently to preventdifferent roe feeding times of the hatching barrel. Egg envelope lytic enzymes released by roes without membranes input into the hatching barrel early to water enter the hatching barrel along with circulating water and roes are put in the hatching barrel to lead to membrane release of roes put in the hatching pond, so that the hatching rate is reduced; the content of dissolved oxygen in water is improved through water circulation, so that the hatching rate is prevented from being reduced as a result of oxygen deficit in the hatching process. The dosage of water can be reduced, so that the system is energy-saving and environment-friendly. By arranging the hatching barrels, the temporary raising basin and the fry pond on the rack to form a three-layered three-dimensional structure, an intactfry hatching culture process can be finished, so that the intermediate transfer links are reduced, the hatching efficiency is improved and the production cost is lowered.

The invention discloses a polyodontidae fry breeding device, which is composed of a cylindrical placenta isolating pond, a motor, a mixer, a motor front and back direction controller, a first linkingpipe, a spawn incubation pond, a constant temperature pond, a second linking pipe, a first filter, a first water pump, a first water guide pipe, a second water pump, a second water guide pipe, a temperature control meter, a heating pipe, a temperature probe, a third link pipe, and a fry breeding slot. The polyodontidae fry breeding device can rapidly separate and demould the placenta of the wholepolyodontidae and form a single spawn without hurting the unshelled spawn; the spawn is cultivated under the best temperature and environment, the fry cultivating cycle is short, and the fry hatchingspeed is over one-time faster than that of the traditional method; besides, the fry quality is good. When the fry is bred by the polyodontidae fry breeding device, the polyodontidae fry breeding device with high degree of automation has the advantages of greatly reducing the labor intensity, reducing the fry malformation and improving the unshelling rate and the hatching rate.

The invention discloses a special multivitamin immunopolysaccharide microemulsion preparation for waterfowl. Each 1050 parts of the special multivitamin immunopolysaccharide microemulsion preparation for the waterfowl by weight comprises a traditional Chinese medicinal extract, 51.11-102.52 parts of multivitamin, 25.5-51.5 parts of polysaccharide and 12.5-25 parts of sunflower seed oil by weight, wherein the traditional Chinese medicinal extract is obtained by performing alcohol extraction on the following traditional Chinese medicinal raw materials in parts by weight: 200-250 parts of honeysuckle, 350-400 parts of radix bupleuri, 400-450 parts of indigowoad leaf, 150-200 parts of rheum officinale, 100-150 parts of motherwort, 100-150 parts of radix gentianae and 60-80 parts of liquorice. The invention aims to provide the special multivitamin immunopolysaccharide microemulsion preparation for the waterfowl, which can quickly supplement nutrition, resist diseases and promote growth. The invention also aims to provide a preparation method and specific application of the special multivitamin immunopolysaccharide microemulsion preparation for the waterfowl.

The invention relates to a Chinese softshell turtle breeding method. The method comprises a parent breeding process. The parent breeding process comprises the following steps: before the parents are put into a breeding pond, adding quick lime into the breeding pond to carry out water pond cleaning, pumping the water in the breeding pond and sun drying the pond; refilling the pond with water, sterilizing the parents with povidone iodine solution and then putting the parents into the breeding pond; performing bait feeding and water quality control by stages, wherein the bait comprises a turtle feed, fresh fishes and / or shrimps and vegetable; the water quality control enables the transparency of water in the breeding pond to be 25-40 cm by water change operation. The method is more scientific and is easy to produce and operate, in general the parent breeding process greatly improves the egg yield of parents and the hatching rate of turtle eggs, and moreover the vitality and the survival rate of the hatched juvenile soft-shelled turtles are greatly improved.

The invention relates to an insecticidal composition. The active component of the insecticidal composition is composed of milbemycins and spiromesifen according to a weight ratio of 1:1-1:200. Compared with the activity of single components, the insecticidal composition has a prominently synergistic activity, when the weight ratio of milbemycins to spiromesifen is in the abovementioned range. The provided insecticidal composition is used to prevent and control pests, in particular, panonychus citri, tetranychus cinnabarinus, tetranychus urticae, psylla chinensis, bemisia tabaci, aphid, plutella xylostella, cnaphalocrocis medinalis, chilo suppressalis, and the like. The invention also provides a method of preventing or controlling the invasion of pests. According to the method, milbemycins and spiromesifen are sprayed on target useful plants or environment of target useful plants, target pests or environment of target pests, and target useful plant propagating materials in a random expected sequence or simultaneously. The invention also provides a method of preventing seeds, seedling roots, and branches from the invasion of pests in soil and on leaf surfaces.

The invention provides a method for preventing and controlling loopworms, and relates to the technical field of prevention and control of insects. The method for preventing and controlling loopworms comprises the following step: after sunset every day, illuminating the region about to prevent and control the loopworms with yellow light or green light until sunrise next day. The research show thatafter the region is illuminated with yellow light or green light at night, the spawning habit of adult loopworms can be affected remarkably, incubation of loopworm eggs can be affected remarkably, andthe emergence number of the adult loopworms can be affected remarkably. The biological characteristics of the loopworms under illumination of the yellow light or green light at night are deeply researched by a light behavior method, thus, the method for preventing and controlling the loopworms is high in selectivity and high in interference efficiency, natural enemies of the loopworms are not threatened, and ecological diversity of the insects is protected. By the method, pesticide is not required. Compared with an existing method, the method is more environmentally friendly.

Aiming at the adverse effect of sticky fertilized eggs on artificial propagation and scientific research, the invention provides a method for debonding sticky fertilized eggs of marine fishes. According to the method, a tannic acid seawater solution with a specific concentration is used for debonding the sticky fertilized eggs, the method comprises the steps of debonding solution preparation, inflating embathe, washing, counting and the like, and finally, the debonded fertilized eggs are artificially hatched, so that the hatchability is remarkably improved. The method is good in debonding effect, the debonding of fertilized eggs is uniform and thorough, damage to the fertilized eggs is reduced to the maximum extent, the hatching rate of the sticky fertilized eggs of artificially cultured marine fishes is increased, and the technological method is simple and high in debonding speed.

The invention relates to an insecticidal composition and particularly relates to an insecticidal composition comprising a first active substance tolfenpyrad and a second active substance cycloxaprid. The insecticidal composition comprises tolfenpyrad and cycloxaprid, wherein the weight ratio of tolfenpyrad to cycloxaprid is 1:100-100:1. The insecticidal composition has the advantages that tolfenpyrad and cycloxaprid are compounded according to the certain weight ratio, so that the gain effect in preventing and controlling lepidoptera and homoptera insects in the field crops is achieved, the single-dosage use amount of tolfenpyrad and cycloxaprid is reduced, the use cost is reduced and the risk of insecticide resistance generated by insects is reduced.

The invention relates to the technical field of marine economic shellfish cross breeding, in particular to a breeding method based on argopecten purpuratus, argopecten irradians and Argopecten irradians concentricus three-way hybrid scallop commodity fries. The argopecten irradians and the Argopecten irradians concentricus are subjected to intersubspecific hybridization, then the obtained first-generation scallops of the intersubspecific hybridization and the argopecten purpuratus are used as seed scallops and are respectively subjected to high selfing purification, and the obtained purified sea and ink sea (or ink sea) hybrid scallops and the argopecten purpuratus are subjected to interspecific hybridization; therefore, large-scale preparation of the sea-black-black-purple (or black-sea-black-purple) three-way hybrid scallop commodity offspring seeds is realized. According to the method for preparing the three-way hybrid scallop commodity offspring seeds of the Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus, Argopecten purpuratus,

The invention relates to a method for hatching and cultivating goldfish eggs in an indoor chamber. Calcium gluconate, sodium chloride, magnesium chloride hexahydrate, 4-hydroxyethylpiperazine ethanesulfonic acid solution, methylene blue, and water were made into hatching culture stock solution according to the proportion, and then diluted into hatching culture solution of three dilutions respectively. Put the hatching culture medium with a dilution of 5% in the spawning tank, and put the broodstock in the same spawning tank with the artificial fish nest prepared in advance with a male-to-female ratio of 3 to 2:1 for fertilization. The artificial fish nest with eggs was taken out, rinsed with a 5% hatching culture solution, and then hung in the hatching tank for 1-day hatching. The hatching tank is a hatching medium with a dilution of 10%. After hatching for 1 day, add a hatching medium with a dilution of 15% for incubation for 3 to 5 days, and the fry can emerge. Through the control test, adopting the method of the present invention, the hatching rate is 82-94%, the fry survival rate is 85-95%, and the fry deformity rate is 0.2-0.3%.

The invention provides a breeding method for improving the commercial specification and the commercial rate of freshwater shrimps. The breeding method comprises the following steps: clearing a pond, and planting cold-resistant waterweeds; putting young shrimps bred in winter and spring; catching the freshwater shrimps for marketing for the first time; catching the freshwater shrimps for marketing for the second time; clearing the pond, and planting high-temperature-resistant waterweeds; putting young shrimps bred in summer; replacing bottom-layer water of the pond, and spreading quicklime, a bottom-sediment improver and an organic acid detoxifying agent into the pond; when the content of dissolved oxygen of the pond is 3 mg / L or less, introducing oxygen into the pond; and alternately applying the bottom-sediment improver and the organic acid detoxifying agent, and catching all the freshwater shrimps in the pond for marketing. The breeding method has the following beneficial technical effects: through technological innovation in the aspects of control of water quality, a stocking manner of the young shrimps, planting of the waterweeds, feed selection and feeding, catching, etc., a proper shrimp load density of the pond is maintained, and the survival rate of the freshwater shrimps is improved. Through technical measures of the invention, a unit net profit reaches 5000 to 8000 yuan which is 2 to 4 times of the unit net profit of traditional breeding.

The invention belongs to the technical field of chick embryo hatchery environment illumination, and particularly relates to a method capable of improving the proliferation activity of skeletal muscle satellite cells in the chick embryo hatching period. The method specifically includes the step that illumination with light in different colors is adopted for hatching in the chick embryo hatching period. The light in different colors includes white light, red light, green light and blue light, preferably, green light. The hatching temperature is kept to be 37+ / -0.5 DEG C, and the humidity is kept to be 50%-60%. As for the light regime, 24 h full illumination is carried out, and the illumination intensity is 15 lx. By improving the proliferation activity of skeletal muscle satellite cells in the chick embryo hatching period, the weight of broiler chickens in hatching and the antioxidant level of skeletal muscles after hatching are effectively increased, and the meat quality is improved.

The invention relates to an insecticidal composition. The active component of the insecticidal composition is composed of (A) milbemycins and (B) at least one neonicotine compound. The weight ratio of the active component (A) to the active component (B) is 1:100-100:1. Compared with the activity of single components, the insecticidal composition has a prominently synergistic activity, when the weight ratio of the active component (A) to active component (B) is in the abovementioned range. The provided insecticidal composition is used to prevent and control pests, in particular, panonychus citri, tetranychus cinnabarinus, tetranychus urticae, psylla chinensis, bemisia tabaci, aphid, plutella xylostella, cnaphalocrocis medinalis, chilo suppressalis, and the like. The invention also provides a method of preventing or controlling the invasion of pests. According to the method, the active component (A) to active component (B) are sprayed on target useful plants or environment of target useful plants, target pests or environment of target pests, and target useful plant propagating materials in a random expected sequence or simultaneously.

The invention relates to an insecticidal composition, which contains active compounds SYP-9625 and spirobudiclofen in a weight ratio of 50:1-1:50. The invention also relates to use of the insecticidalcomposition in prevention or control of psyllidae, chrysomelidae, cicadellidae and whitefly pests. The invention also relates to a method for prevention or control of psyllidae, chrysomelidae, cicadellidae and whitefly pests. The insecticidal composition provided by the invention can be applied to seeds, target useful plants or plant growth soil, or soil suitable for plant growth.

The invention relates to an insecticidal composition. The active component of the insecticidal composition is composed of (A) milbemycins and (B) at least one neonicotine compound. The weight ratio of the active component (A) to the active component (B) is 1:100-100:1. Compared with the activity of single components, the insecticidal composition has a prominently synergistic activity, when the weight ratio of the active component (A) to active component (B) is in the abovementioned range. The provided insecticidal composition is used to prevent and control pests, in particular, panonychus citri, tetranychus cinnabarinus, tetranychus urticae, psylla chinensis, bemisia tabaci, aphid, plutella xylostella, cnaphalocrocis medinalis, chilo suppressalis, and the like. The invention also provides a method of preventing or controlling the invasion of pests. According to the method, the active component (A) to active component (B) are sprayed on target useful plants or environment of target useful plants, target pests or environment of target pests, and target useful plant propagating materials in a random expected sequence or simultaneously.

A production method for euproctis pseudoconspersa nuclear polyhedrosis virus belongs to the technical field of microbial pesticide production. The production method comprises the following technological steps: 1) large-scale breeding of larva; 2) virus propagation; 3) virus collection; and 4) virus extraction. The production method comprises the following beneficial effects: firstly, skin allergy caused by toxic hair of euproctis pseudoconspersa is prevented, because the probability of euproctis pseudoconspersa toxic hair contamination is substantially reduced by exchanging forage in a fume cupboard and collecting euproctis pseudoconspersa dead bodies, and allergy is effectively avoided; secondly, the virus production yield is improved, by employing potted tea trees for producing overwintering spawns, the hatching rate of the overwintering spawns is substantially improved from 10-15% to 65-80%, so that first-generation larva breeding number and virus productivity in next year are ensured; and also, the virus dried dead body collection method is employed, helps to reduce the loss of virus during collection, and is improved in efficiency by 52.7% and in virus productivity by 38.8% compared with a conventional collection method.

The invention relates to an insecticidal composition. The active component of the insecticidal composition is composed of milbemycins and indoxacarb according to a weight ratio of 1:100-100:1. Compared with the activity of single components, the insecticidal composition has a prominently synergistic activity, when the weight ratio of milbemycins to indoxacarb is in the abovementioned range. The provided insecticidal composition is used to prevent and control pests, in particular, panonychus citri, tetranychus cinnabarinus, tetranychus urticae, psylla chinensis, bemisia tabaci, aphid, plutella xylostella, cnaphalocrocis medinalis, chilo suppressalis, and the like. The invention also provides a method of preventing or controlling the invasion of pests. According to the method, milbemycins and indoxacarb are sprayed on target useful plants or environment of target useful plants, target pests or environment of target pests, and target useful plant propagating materials in a random expected sequence or simultaneously.

The invention discloses a method for obtaining nilaparvata lugens new strains stably infected with Cardinium by artificial transfection and belongs to the technical field of agricultural biology. According to the method, eggs newly laid by sogatella furcifera and nilaparvata lugens are used as a donor and a receptor for artificial transfection respectively, and a cytoplasm component of the donor is sucked by a micro-injection instrument and rapidly injected into receptor eggs. The receptor eggs are cultured and developed into primary female adults (G0), the primary female adults are mated with non-infected males to produce a first generation (G1), and infected positive females are screened from the G1 to be continuously mated with non-infected males to produce a second generation (G2). The G2 and the G1 are detected to be positive, so that the nilaparvata lugens new strains stably infected with Cardinium are obtained successfully. The method can be used for rapidly establishing the nilaparvata lugens new strains infected with Cardinium, the fertility and hatching rate of the new strains are significantly reduced, so that harm of the nilaparvata lugens is controlled. The invention also provides models for transfection of other symbiotic bacteria.