CN1421130A - Low-cost interlinear silkworm hybrid breeding method - Google Patents

Abstract

The interlinear silkworm hybrid breeding method includes high hatchability non-meiotic female parthenogenesis to propagate the female parent as hologynic filial generation for silkworm hybrid, egg color limiting process to propagate the male parent as holandric filial generation for silkworm hybrid ,and hybridization with the two parents to produce interlinear silkworm hybrid. The present invention has low hybrid breeding cost to raise high-quality new silkworm hybrid with high feed efficiency.

Description

Silkworm low breeding cost interlinear silkworm hybrid breeding method

Technical field

The present invention relates to silkworm low breeding cost interlinear silkworm hybrid breeding method.

Background technology

Silkworm all utilizes crossbreed on producing, because present production can not artificially be controlled with the original seed sex major part of planting, the hybridization parents have the male and female individuality, thereby on producing, positive and negative 2 of first generation cross-fertilize seed is handed over all must utilization.This not only can not satisfy seed station and support the requirement that female silkworms are supported male silkworm less more, has increased breeding cost, and makes and can't utilize silkworm sex-linked inheritance principle in the silkworm breeding, the crossbreed parents is provided with different seed selection emphasis, to simplify breeding goal.And crossbreed reciprocal cross both sides will utilize, and must consider reciprocal cross both sides' characteristic trait during assembly hybrid combination simultaneously, greatly reduce the success rate that improved seeds are selected, and have also limited the raising of cultivated silkworm breed variety economic characters.

The silkworm artificial parthenogenesis is meant the fusion without gamete between bisexuality, and the unisexuality individuality is stimulated by certain physical, impels the nucleon self in the reproductive cell to merge, and develops into a newborn individuality.Silkworm ameiosis parthenogenesis (Ameiotic parthenogenesis. is called for short AMP) is a kind of of silkworm artificial parthenogenesis.Confirmed by cell and genetics research: the individuality that is produced by the AMP method is for female entirely, and the AMP individuality is the genotype that has copied previous generation's parent, so the offspring is not only identical with previous generation's genotype, and also also in full accord with genotype between moth offspring individuality.The gynecogenic incidence of ameiosis is extremely low under field conditions (factors), with manually unfertilized egg being carried out physical stimulation, can improve this apomictic incidence, but its artificial incidence of general conventional variety is also lower, no practical value.The silkworm sex-limited egg color species is a kind of special silkworm kind by Gene Handling silkworm egg look, general female ovum is a black egg, male ovum is white ovum, present this kind is as the germ plasm resource of silkworm and preserve, because of its economic characters relatively poor, only on genetics research, use,, in common species production, do not have application example except that specially supporting the male silkworm technology.

Summary of the invention

The purpose of this invention is to provide a kind of silkworm low breeding cost interlinear silkworm hybrid breeding method.Cultivate the high-quality new silkworm variety of high feed efficiency.

Technical scheme of the present invention is as follows:

1) by gene importing or selection, gene accumulation method, cultivate practical incubation rate more than 50%, the silkworm ameiosis parthenogenesis parent material that economic characters are good is helped female maternal original seed;

2) by the method for crossbreeding incorporation of markings gene Selection, cultivate the sex-limited ovum look of the silkworm parent material that practical economic characters are good, coordinate force is good, distinguish male and female according to the ovum look, it is male to select and remain, and makes the male parent original seed of full hero;

3) use the repeatedly characteristic of mating of the male moth of silkworm, the number of animals raised ratio of control male and female original seed is maternal original seed: male parent original seed=2～2.5: 1, then male parent original seed and the hybridization of maternal original seed are made the single cross first generation cross-fertilize seed.

The effect that the present invention is useful:

1) utilizes silkworm sex controlling technology, carry out the single cross production of hybrid seeds of first generation cross-fertilize seed.Crossbreed parents original seed one side only supports female, and the opposing party only supports male, utilizes the repeatedly characteristic of mating of male moth again, and original seed is raised female-male proportion and can be controlled in ♀: on ♂=2: 1 level, can lack original silkworm rearing amount 1/4.

2) according to research, the main economic characters of silkworm all belong to sex-linked inheritance, adopt the single cross production of hybrid seeds, and reciprocal cross no longer utilizes, and when the parental breed seed selection, thereby can to the father and mother parent different selection emphasis be set according to silkworm sex-linked inheritance rule.Select unconventional good silkworm kind.

3) female parent is an ameiosis parthenogenesis system in this method, and this method filial generation is the genotype that copies the previous generation fully, so gene structure ten minutes homogeneous has higher hybrid vigour after the hybridization.

4) because original seed one side only supports malely, and that the opposing party only supports is female, can not the generation selfing during production of hybrid seeds pure right, the hybridization that can guarantee first generation cross-fertilize seed completely.

5) as the original seed of parent silkworm rearing, wish its voluminous ovum, improving seed production efficiency, and, wish its fecund silk again, lay eggs less, to improve feed efficiency as the crossbreed of raw cocoon production.In conventional double cross method seeding technique, because of parents' male and female all will be utilized, being difficult to coordinate original seed has different this a pair of contradictions that require with crossbreed to egg laying amount.And in the single cross production of hybrid seeds, because of a side only supports female silkworm, only a side only supports male silkworm, and egg laying amount only utilizes dam side, male parent side no longer is required to improve egg laying amount, thereby can when seed selection, only consider to increase female side's egg laying amount, to improve seed production efficiency, utilize the patroclinal ingeritance characteristic of silkworm egg laying amount simultaneously, the egg laying amount of the male parent side of control just can reduce the first-filial generation egg laying amount, to improve the feed benefit of hybrid.

The present invention can reduce the breeding cost of f_1 hybrid eggs of silkworm significantly, cultivates the high-quality new silkworm variety of high feed efficiency.

Embodiment one: parent's seed selection embodiment of the single cross production of hybrid seeds

(1) carries out test cross with common silkworm variety, find out wherein and one hand over the good especially double cross combination of integral economic trait, according to the good friendship combination that filters out, determine transformation improvement parent then;

(2) common silkworm variety is because without special selection, the gynecogenic practical incubation rate of its artificial ameiosis is very low, thereby the first step is that the ameiosis parthenogenesis of this parent and existing high hatchability system is backcrossed, again through selecting, can breed also that practical economic characters are good, incubation rate is at the artificial ameiosis parthenogenesis new silkworm breed more than 50%; Perhaps, progressively accumulate the practical incubation rate of the parthenogenesis that improves current race by selecting.And when selecting to improve its practical incubation rate, note improving its practical economic characters.Through the several generations seed selection, breed that practical economic characters are good, incubation rate is at the artificial ameiosis parthenogenesis new silkworm breed more than 50%;

(3) hybridization by current race and sex-limited egg color species, backcross, the incorporation of markings gene Selection, the transformation current race becomes the good sex-limited egg color species of economic characters;

(4) be parthenogenesis as maternal, pick out the male male parent of doing of sex-limited ovum colour system.To mating system single cross hybrid combination, by test cross relatively, filter out good single cross hybrid combination.Two: embodiment in the actual production

(1) maternal colony utilizes ameiosis parthenogenesis method, produces complete female colony, plants subculture and produces original seed as mother.

(2) male parent colony is the selfing subculture with sex-limited ovum chromaticity, according to the ovum look, selects the male original seed of doing of white ovum, and female black egg is eliminated.

(3) seed station can be in female: the ratio of male=2～2.5: 1 is raised 2 parental stocks, hybridizes manufacture order then and hands over crossbreed.Three: biological example

Tens of the maternal materials of the good ameiosis parthenogenesis that has practical value of economic characters have now been bred in research through 7 years, and its practical incubation rate is all more than 60%.And bred about 10 of the good sex-limited ovum colour system of integral economic trait again, by test cross relatively, found out the good single cross hybrid combination of several integral economic traits, as do not had 3 * ovum 32, do not have 5 * ovum 26 etc.

Spring in 2002, do not have the test achievement of 3 * ovum, 32 its parents and crossbreed and list in table 1 and table 2.From this 2 table as seen, the single cross of preparation combination should have practical value in this way, passes through on purpose to select to improve again, and can obtain very good production hybrid combination.

Table 1 spring in 2002 ameiosis parthenogenesis system's nothing 3 and sex-limited ovum colour system ovum 32 original seeds are raised achievement

The kind name	Practical incubation rate (%)	Five ages are through (D: H)	Full age is through (D: H)	The rate of cocooing (%)	Worm pupa rate (%)	Cocoon weight (g)	Cocoon shell weight (g)	Cocoon layer rate (%)
									Do not have 3	??63.69	??8∶07	??25∶12	??91.78	??86.01	????2.17	????0.432	????19.90
Ovum 32	??96.51	??7∶15	??24∶12	??95.32	??92.82	????1.73	????0.350	????20.25

Table 2 spring interlinear hybrid in 2002 does not have 3 * ovum, 32 sericulture filature achievements

The kind name	Five ages are through (D: H)	Full age is through (D: H)	The rate of cocooing (%)	Worm pupa rate (%)	Cocoon weight (g)	Cocoon shell weight (g)	Cocoon layer rate (%)	Ten thousand silkworm amount of cocoon crop (kg)	Ten thousand silkworms produce cocoon shell weight (kg)
										There is not 3 * ovum 32	???7∶02	??24∶07	??98.57	??96.60	??2.02	??0.429	??21.24	????19.43	????4.126
Qiu Feng * white jade	???7∶08	??23∶05	??96.64	??94.46	??1.98	??0.405	??20.51	????18.68	????3.832

The kind name	Silk long (m)	Length of non broken filament (m)	Reelability percentage (%)	Silk amount (g)	The size of cocoon filament (D)	Cleanliness (branch)	Bright cocoon silk production rate (%)
								There is not 3 * ovum 32	????1097	???586	????53.43	????0.3410	????2.797	????96.00	????15.88
Qiu Feng * white jade	????1103	???609	????55.20	????0.3189	????2.601	????95.50	????14.66

Annotate: Qiu Feng * white jade is to produce with conventional double cross contrast to plant.The gynecogenic practical incubation rate of silkworm ameiosis is higher than 50%, surpassed conventional variety this its practical value, because ameiosis parthenogenesis hatching is female silkworm entirely, and conventional variety is only hatched 1/2 female silkworm, and its practical incubation rate can not reach 100%.

Claims (1)

1. silkworm low breeding cost interlinear silkworm hybrid breeding method is characterized in that:

1) by gene importing or selection, gene accumulation method, cultivate practical incubation rate more than 50%, the silkworm ameiosis parthenogenesis parent material that economic characters are good is helped female maternal original seed;

2) by the method for crossbreeding incorporation of markings gene Selection, cultivate the sex-limited ovum look of the silkworm parent material that practical economic characters are good, coordinate force is good, distinguish male and female according to the ovum look, it is male to select and remain, and makes the male parent original seed of full hero;

3) use the repeatedly characteristic of mating of the male moth of silkworm, the number of animals raised ratio of control male and female original seed is maternal original seed: male parent original seed=2～2.5: 1, then male parent original seed and the hybridization of maternal original seed are made the single cross first generation cross-fertilize seed.