• International Journal of Industrial Entomology and Biomaterials
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• 제19권1호
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• pp.187-192
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• 2009

Silk filament progression study applying backcross breeding with recipient parent Jata and donor parent Daba ecoraces of tropical tasar silkworm, Antheraea mylitta Drury conducted during 2006 to 2008, revealed introgression of filament denier (10.2 d) superior to both parents at BC4 level. Also, the silk waste (0.35%) and filament breaks (2.6 nos) were reduced compared to both parents, while the filament length (973 m) and non break filament (296 m) improved over donor and could attain closer to recipient parent. The best performance of Jata $\times$ Daba at F1 level, with highest silk filament length (1646 m) of 12.5 d denier, denotes heterosis impact on silk trait with parental heterogenousity, an advantage to exploit silk filament yield. The progression of quality in terms of finer filament denier, less silk waste and least number of filament breaks over both parents and improvement in filament length and non break filament over donor parent except for a marginal shortage against recipient at BC4 level indicates the prospects of Jata and Daba ecoraces as source of breeding material for qualitative improvement of tasar silk filament. The study suggests that the commercially important finer denier of tasar silk filament can be attained with minor reduction in silk yield of wild Jata ecorace by adopting repeated backcrossing for four generations with semi domesticated Daba ecorace.

• 한국자원식물학회지
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• 제22권3호
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• pp.209-214
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• 2009

To facilitate the introgression of F. esculentum into the traits of F. homotropicum, several accessions of the hybrids between these two species were pollinated with F. esculentum as the recurrent parent. The embryo in vitro rescue was performed to increase the recovery of backcross progenies. The $F_{2}$ generation was more amenable than $F_{1}$ hybrids to produce backcross progenies. The $F_{1}$ hybrids were backcrossed twice with common buckwheat (pin-type F. esculentum) (recurrent backcrossing). Also, alternate backcrosses with common buckwheat and F. homotropicum (congruity backcrossing) were carried out. Pollen tube growth of BC$F_{1}$ ${\times}$ F. esculentum (thrum) and F. homotropicum ${\times}$ BC$F_{1}$ was the disturbed penetration exceeded for all initial interspecific hybrids, and its requirement was proportionally lower when the common buckwheat was used as the recurrent parent and as the last parent of congruity hybrids. Effects of both common buckwheat and F. homotropicum on seed success rate for hybridization were observed. Growth of hybrid embryos before rescue, regeneration of mature hybrids all increased recurrent and congruity backcrosses and inter-crosses between $F_{1}$ plants and selected fertile plants of the second congruity backcrosses.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
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• pp.271.1-271
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• 2000

No Abstract, See Full Text

• Mycobiology
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• 제32권1호
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• pp.11-16
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• 2004

Winter mushroom, Flammulina velutipes, needs low temperature during its cultivation. To save on farm costs, especially during summer, a strain adaptable to a higher or elevated-temperature must be developed. At the start of breeding program, parental strains which could endure high temperature were obtained. Seuenty four dikaryotic strains were collected and divided into four groups according to the nature of temperature. They also had different fruiting temperature. Finally we selected three brown strains ASI 4048, 4057 and 4072, and collected their spores. These selected strains can germinate even at a high temperature of $32^{\circ}C$, which were dramatically higher than the other strains. Based on these results, the new white strain adapted to mid-temperature by backcross mating was developed. Molecular markers were applied to select white fruitbody producing strains without cultivation. They showed a specific band which co-segregated with brown fruitbody forming strains in $BC_1F_1$ progenies. Selected white strains were tested under several elevated temperature conditions.

• Journal of Plant Biotechnology
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• 제1권1호
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• pp.8-12
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• 1999

New winter wheat winter barley hybrids were produced (Mv9 kr1 Igri, Mv9 kr1 Osnova, Asakazekomugi Manas). The wheat-barley hybrids showed entire male sterility and were multiplied in tissue culture. Chromosome configurations were studied with GISH in meiosis in the Mv9 krl x Igri hybrid and in its progenies multiplied in vitro. Chromosome pairing between wheat and barley has been observed in some cells in the hybrids multiplied in vitro. Backcross plants with 43 and 44 chromosomes were selected with the aim of developing new wheat-barley addition lines. Wheat-barley translocations were demonstrated with GISH in backcross progenies originating from in vitro regenerated wheat (Triticum aestivum L. cv. Chinese Spring) x barley (Hordeum vulgare L. cv. Betzes) hybrids. Five different translocations were observed. Sequential N-banding and GISH analyses were performed to further identify the translocations. The N-banding pattern of the Robertsonian translocation suggests that this chromosome consists of the short arm of barley chromosome 4H translocated to the long arm of 2B of wheat. Plants with four different homozygous translocations were selected from the following BC2F3 generation.

• Asian-Australasian Journal of Animal Sciences
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• 제17권7호
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• pp.954-959
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• 2004

In a herd of 24 spring-born steers, plasma leptin and performance of selected purebred (n=5) and backcrossed Hereford (n=5) were compared in a year-round summer grazing and winter feedlot fattening. Bimonthly blood collection and body weight measurement were accomplished. The plasma samples were analyzed for leptin, insulin, total cholesterol, triglyceride, NEFA and glucose. The experimental design utilized one-way ANOVA with breed as the treatment. The purebred obtained higher plasma NEFA (p<0.001) compared to backcross, regardless of seasonal feeding systems (SFS). The backcross showed gradual increase and nonresponsiveness of plasma leptin to SFS. During summer grazing, attenuation of plasma leptin and sudden elevation when shifted to winter feedlot fattening were observed in purebred. Plasma leptin obtained linear relationship with body weight of purebred (r=0.53;p<0.001) and backcrossed Hereford (r=0.49; p<0.01). The purebred and backcrossed Hereford, when shifted to summer grazing, resulted to sustained and restricted daily gain, respectively. Therefore, cattle breeds of higher growth potential exhibit significant elevation of plasma leptin after 400 kg BW, when animal starts to deposit significant body fat.

• Current Research on Agriculture and Life Sciences
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• 제12권
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• pp.29-34
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• 1994

감미종(甘未種)고추에 역병저항성(疫病抵抗性)을 도입하기 위하여, 품질이 우수하면서 국내 적응성이 뛰어난 피만계 품종 Keystone Resistant Giant #3과 역병에 저항성이며 과실이 피만계와 가까운 PI201232를 교배하여 그 후대(後代)의 유전적인 분리 양상을 조사하였다. $F_1$에서는 저항성이 우성(優性)으로 나타났으나 $F_2$ 집단의 경우 고사(枯死)한 개체가 살아남은 개체보다 월등히 많아 저항성이 한 개 혹은 두 개의 우성유전자(優性遺傳子)에 의해 지배된다는 기존의 보고와는 다른 양상으로 나타났다. 뿌리에 대한 조사 결과를 볼 대 지상부가 건전한 개체간에도 뿌리 썩음 정도에 변이(變異)가 나타나기 때문에 저항성 품종을 육성하는 과정에서 지상부와 뿌리의 상태를 함께 관찰한 후 선발(選拔)하는 것이 유리할 것으로 사료되었다. 전반적으로 발병(發病)이 심한 것은 품질친(品質親)이 역병에 매우 약하여 분리(分離) 집단(集團)에서 높은 이병성(罹病性)의 유전적(遺傳的)인 배경을 형성한 것과 동시에 접종(接種) 후의 기상 및 환경조건이 역병 발생에 최적조건을 만든 영향으로 사료된다. $BC_1$ 개체가 모두 고사(枯死)하였으므로 $F_2$에서 저항성 개체를 선발한 후 여교잡(戾交雜)과 자식(自殖)을 반복하는 순환적 여교잡(戾交雜)을 실시하는 것이 저항성의 수준을 유지하면서 품질친의 실용 형질을 회복할 수 있을 것으로 사료된다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 춘계 학술대회지
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• pp.36-37
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• 2000

• Current Research on Agriculture and Life Sciences
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• 제10권
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• pp.117-123
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• 1992

우수한 재래종(在來種)에 더뎅이병과 역병 저항성(抵抗性) 인자(因子)를 도입(導入)하기 위한품질친(品質親)을 선발(選拔)하기 위하여 '칼미초'에서 선발한 20계통과 '풍각초'에서 선발한24계통을 공시하여 본(本) 대학(大學) 시험포양(試驗圃楊)에 재배(栽培)하여 개화소요일수(開花所要日數), 초장 및 과실특성을 조사(調査)하였다. '칼미초'와 '풍각초' 선발 계통(系統)들은 모두 개화소요일수(開花所要日數)가 많은 만생종(晩生種)이었고, '칼미초' 계통들이 '풍각초' 보다 변이복(變異福)이 더 크게 나타났다. '칼미초'의 일부 계통(系統)들은 초세(草勢)가 강하고 당도(糖度)가 높으며 포양(圃楊)에서 바이러스에 저항성(抵抗性)으로 나타났다. '풍각초'의 일부 계통(系統)은 과종(果種)이 무거운 대과종(大果種)이었으며 과피가 두텁고 제분율(製粉率)이 높게 나타났다. 이상(以上)의 결과(結果)로서 더뎅이병과 역병에 저항성(抵抗性) 품종(品種)을 육성하기 위한 여고잡육종에서 반복친으로 사용할 수 있는 재료(材料)로 '칼미초' 계통 6, 9, 14, 18과 '풍각초' 계통 14, 16, 18등 7계통(系統)을 선발(選拔)하였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.265-265
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• 2017

This study was carried out to develop rice variety integrated with rice bacterial blight resistance gene and to know the information of major agronomic traits of developed variety. Advanced backcross Lines 21 having Xa3 and Xa21 gene cross from japonica cultivar Hwanggeumnuri and indica variety IRBB21. Days after seeding and culm length of ABLs21 were 108 days (Aug. 16) and 76 cm, respectively. Ripened grain rates was 87.4 %, which was similar to the parents. 1000 grain weight of brown rice of ABLs21 was 21.4g, which was lower than the donor parent. Milled rice yield of ABLs21 was 532 kg/10a, which was smaller than recurrent parent and higher than the donor parent. Grain length/width ratio of brown rice was form of japonica with short-ellipse and glossiness of cooked rice has japonica trait. Head rice rate showed a large difference compare to the donor parent and similar to the recurrent parent. ABLs21 would be useful genetic resources for resistance breeding program against bacterial blight.