CN-121986762-A - Breeding method of yellow-white cocoon color-limited silkworm variety

CN121986762ACN 121986762 ACN121986762 ACN 121986762ACN-121986762-A

Abstract

The invention provides a breeding method of yellow and white cocoon color-limited silkworm varieties, belonging to the technical field of silkworm breeding. The invention establishes a stable inheritance medium-line yellow and white cocoon color-limited strain 781F, a firewood Hangzhou F and a daily-line yellow and white cocoon color-limited strain Keming F and 7532F through multi-stage directional breeding, obtains medium-line stock seeds and daily-line stock seeds through medium-day hybrid crossing, and obtains a new yellow and white cocoon color-limited combination (781F. Firewood Hangzhou F x 7532F. Keming F) through 4-element hybrid combination. The female silkworm golden cocoons and the male silkworm white cocoons bred by the breeding method can realize cocoon color limit detection, the male and female resolution accuracy reaches 100%, and meanwhile, the method has the characteristics of good robustness, high vitality and large silk yield, greatly shortens the breeding period and has higher popularization and application values.

Inventors

YANG WANJUN
HU SHIYE
YE ZHANFENG
REN XIAOXIAO
LUO CHAOBIN
ZENG XIAOYING
HE JING
Han Chenmin
ZOU BANGXING

Assignees

贵州省蚕业研究所(贵州省辣椒研究所)

Dates

Publication Date: 20260508
Application Date: 20260319

Claims (10)

1. A breeding method of yellow-white cocoon color-limited silkworm varieties is characterized by comprising the following steps: Taking a medium-line strain containing cocoon color-limited genes as female parent, respectively taking 781 and paycheck parents as recurrent parents for backcross and selfing, and establishing a medium-line yellow and white cocoon color-limited strain 781F and paycheck F with stable inheritance; Performing forward and backward crossing on the medium-series yellow and white cocoon color limited strain 781F and the firewood Hangzhou F to obtain medium-series stock 781F multiplied by the firewood Hangzhou F material; The daily line strain containing the cocoon-color-limited gene is used as a female parent, and the Keming and 7532 are respectively used as recurrent parent, and after backcross and selfing, stable genetic daily yellow and white cocoon-color-limited strains Keming F and 7532F are established; the daily yellow and white cocoon color limited strains Keming F and 7532F are subjected to forward and reverse crossing to obtain a daily stock 7532F multiplied by Keming F material; And (3) hybridizing and assembling the medium-line stock 781F multiplied by the firewood Hangzhou F material and the daily-line stock 7532F multiplied by the Keming F material to obtain the yellow and white cocoon color-limiting material 781F multiplied by the firewood Hangzhou F multiplied by 7532F multiplied by the Keming F.
2. The method according to claim 1, wherein the material carrying the target trait is obtained by selecting at least one of egg stage, larval stage, cocoon stage and moth stage during establishment of a stably inherited medium yellow white cocoon color-limited strain 781F and salary Hangzhou F or daily yellow white cocoon color-limited strain keming F and 7532F.
3. The method according to claim 2, wherein the egg period selection is to select the moth area with the top of the comprehensive score of total egg number, hatching rate, non-fertilized egg rate and dead egg rate of the moth area for seed reservation.
4. The method of breeding according to claim 3, wherein the egg period is selected by selecting the moth region with 20% of the ranking of the comprehensive score for the F1-F3 generation and selecting the moth region with 40% of the ranking of the comprehensive score for the F4 generation.
5. The breeding method according to claim 3 or 4, wherein the integrated score is calculated according to formula I: The egg period selection comprehensive score=2×hatchability score+non-fertilized egg rate score+dead egg rate score+total egg number score formula I; The hatching rate score, the non-fertilized egg rate score, the dead egg rate score and the total egg number score are divided into 5 grades according to the statistical result of each moth area, and respectively correspond to 5, 4, 3, 2 and 1 in order from high to low.
6. The method of claim 2, wherein the larval stage selection comprises selecting a moth field seed for at least one of good feeding, regular development, regular sleep, and healthy.
7. The method for breeding according to claim 2, wherein the cocoon period selection comprises moth area selection and cocoon individual selection in sequence; The moth area selection is to select moth areas with integrated achievements of moth areas with unified life rate, death rate, cocoon setting rate, whole cocoon quantity, cocoon layer quantity and cocoon layer rate, and the comprehensive achievements of the moth areas are ranked at the front; and the individual selection of the cocoons is to select the cocoons with advantages of cocoon layer rate and whole cocoon quantity from the moth region for seed reserving.
8. The method according to claim 2, wherein the period selection of the silkworm moth is to select an individual with normal body color, no wing deficiency and active action as an inbred parent.
9. The breeding method according to any one of claims 1 to 8, wherein the number of backcrosses is 3 and the number of selfs is 5.
10. The use of the breeding method according to any one of claims 1-9 for breeding yellow-white cocoon-color-limited silkworm varieties and/or for improving the vitality and/or silk yield of silkworm varieties.

Description

Breeding method of yellow-white cocoon color-limited silkworm variety Technical Field The application belongs to the technical field of silkworm breeding, and particularly relates to a breeding method of yellow-white cocoon color-limited silkworm varieties. Background The conventional silkworm variety breeding needs to identify the male and female in the pupa period of the original silkworm to realize male and female hybridization. The traditional manual identification of male and female pupas depends on experience, but the low efficiency is easy to damage silkworm bodies, the modern large-scale production requirement cannot be met, and the mechanical separation has the limitation of low accuracy. The genetic strain for producing the female silkworm to spit yellow cocoons and the male silkworm to spit white cocoons is created by introducing and positioning the genes for controlling the yellow cocoons on the W chromosome of the silkworms, so that complete linkage inheritance of the cocoon colors and the sexes is realized, and the male and female traits are naturally separated during cocooning. The technology enables male and female identification to be visual and accurate (approaching 100%), can be carried out at any feeding scale, does not need special equipment or complex technology, fundamentally solves various defects of the traditional sorting technology, is particularly suitable for high-efficiency silk cocoon production aiming at male silkworm feeding, can greatly reduce sorting cost and improves economic benefit. In the existing cocoon color limited varieties, the defects are existed, compared with the conventional varieties, the physique and vitality of silkworm babies of the limited varieties are generally weaker, the whole cocoon quantity and the cocoon layer quantity are also lower, and the reelability rate is unstable or lower. Disclosure of Invention The invention aims to provide a breeding method of yellow and white cocoon-color limited silkworm varieties, which realizes the improvement of indexes such as vitality, whole cocoon quantity, cocoon layer quantity and the like through multi-stage selective cross breeding. The invention provides a breeding method of yellow and white cocoon color-limited silkworm varieties, which comprises the following steps: taking a medium-line strain containing cocoon color-limited genes as female parent, respectively taking 781 and paycheck as recurrent parents to carry out backcross and selfing, and establishing a medium-line yellow and white cocoon color-limited strain 781F and paycheck F which are inherited stably; Performing forward and backward crossing on the medium-series yellow and white cocoon color limited strain 781F and the firewood Hangzhou F to obtain medium-series stock 781F multiplied by the firewood Hangzhou F material; The daily line strain containing the cocoon-color-limited gene is used as a female parent, and Keming and 7532 are respectively used as recurrent parent, and after backcross and selfing, stable genetic daily yellow and white cocoon-color-limited strains Keming F and 7532F are established; the daily yellow and white cocoon color limited strains Keming F and 7532F are subjected to forward and reverse crossing to obtain a daily stock 7532F multiplied by Keming F material; And (3) hybridizing and assembling the medium-line stock 781F multiplied by the firewood Hangzhou F material and the daily-line stock 7532F multiplied by the Keming F material to obtain the yellow and white cocoon color-limiting material 781F multiplied by the firewood Hangzhou F multiplied by 7532F multiplied by the Keming F. Preferably, the material carrying the target property is obtained through at least one of egg stage selection, larva stage selection, silk cocoon stage selection and silk moth stage selection in the process of establishing a stable inheritance medium yellow and white cocoon color-limited strain 781F and firewood Hangzhou F or daily yellow and white cocoon color-limited strain kemin F and 7532F. Preferably, the egg period selection is to select the moth area with the top comprehensive results of the total egg number, the hatching rate, the non-fertilized egg rate and the dead egg rate of the moth area for seed reservation. Preferably, during the egg period selection, the F1-F3 generation selection is carried out on the moth area with 20% of the ranking of the comprehensive score, and the F4 generation later is carried out on the moth area with 40% of the ranking of the comprehensive score. Preferably, the composite score is calculated according to formula I: The egg period selection comprehensive score=2×hatchability score+non-fertilized egg rate score+dead egg rate score+total egg number score formula I; The hatching rate score, the non-fertilized egg rate score, the dead egg rate score and the total egg number score are divided into 5 grades according to the statistical result of each moth area, and respectively correspond to 5, 4, 3, 2 and