• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• v.22 no.1
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• pp.6-23
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• 1994

A disconnection event (DE) of the cometary plasma tail is one of most spectacular phenomena observed in comets. Yet, for years it has remained one of the great unsolved problems I astronomy and space physics. The solar wind is thought to play a major role in the creation of comet plasma tail (type Ⅰ) disconnection events. The goal of this paper is to present a mechanism that explains the disconnection event in terms of the local conditions at the comet. Comparison of the solar wind conditions and 16 DEs in Halley's comet shows that DEs are associated primarily with crossings of the heliospheric sector boundary and apparently not with any other properties of the solar wind, such as a high speed stream[Yi et al., 1994]. A 3-dimensional resistive magnetohydrodynamic simulation in this paper supports this association by showing that only front-side magnetic reconnection between the reversed interplanetary magnetic fields that exist when a comet crosses the heliospheric sector boundary [Niedner and Brandt, 1978] could reproduce the morphology of a DE, including ray formation [Brandt, 1982].

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.4
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• pp.209-212
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• 1988

Thirty-six heifers of three different breeds were fed rice straw, either upgraded with 4% urea, or supplemented with 2% urea, sprayed on the straw just prior to feeding. The effects on liveweight gain and dry matter intake were measured for pure Sahiwal heifers, Sahiwal ${\times}$ local crosses and Jersey ${\times}$ local crosses. Urea upgraded straw gave better growth than urea supplemented straw, average 217 g/day/ animal versus 71 g/day/animal. This was associated with a higher intake of upgraded straw, compared to supplementation straw (2.4 versus 1.8 kg/100 kg BW). No overall breed effect on growth was found (P>0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.2
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• pp.225-234
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• 1993

A total of 333 carcasses were evaluated for hindquarter traits: round weight, percent round, loin weight, percent loin, flank weight and percent flank. Other characteristics included: total retail, lean trim, fat trim, round steaks, rump, sirloin tip, loin steaks, percent loin steaks and flank steaks. Mating types included straightbred Angus and Santa Gertrudis, the reciprocal crosses of these two breeds and Gelbvieh ${\times}$ Angus. Breed of sire and breed of dam were significant for most of the traits evaluated. Calf year and slaughter group were also significant. This could be the result of environmental variations. Effect of sire within sire breed was non-significant for all the traits considered. Heterosis due to interaction between sire breed ${\times}$ dam breed was found significant for percent total retail cuts based on hindquarter weight. Generally, Santa Gertrudis purebreds were more desirable in cut out characteristics than all other breeding types followed by crossbreds of Angus ${\times}$ Santa Gertrudis.

• Animal cells and systems
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• v.2 no.4
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• pp.435-438
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• 1998

In the present study, we have examined the crossability of four species in the A. jaluense complex to provide additional information on their delimitation and levels of differentiation. Crosses between diploid A. chiisanense and the tetraploid species including A. jaluense s. str., A. triphyllum, and A. pseudoproliferum yielded no fruit- or seed-set, indicating that the former species is reproductively completely isolated from the latter three species. In interspecific crosses between the tetraploid species, combinations involving A. jaluense s. str. resulted in much reduced fruit- and seed-set, indicating that A. jaluense s. str. is more or less reproductively isolated from the other tetraploid species. However, crossing data revealed the absence of reproductive isolation between A. triphyllum and A. pseudoproliferum These results strongly support the relationships that have been previously suggested for the A. jaluense complex on the basis of morphology, chromosome number, and flavonoid chemistry.

• The Plant Pathology Journal
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• v.28 no.4
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• pp.418-422
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• 2012

Eleven hot pepper accessions collected in Vietnam showed stable resistance to bacterial wilt as well-known resistance sources, MC4 and MC5, in repeated inoculation tests with different Ralstonia solanacearum isolates conducted from 2004 to 2010. Seven of these accessions (specifically KC981, KC1006, KC1021, KC1027, KC1045, KC1050, and KC1055) resulted in stable male sterile F1 plants in the crosses with a cytoplasmically male sterile (CMS) Chilseong (CMS-A, Srfrf ), and therefore, they were maintainers (CMS-B) with a genotype of Nrfrf. The rest (KC980, KC995, KC999, and KC1009) produced stable male fertile F1 plants in the crosses, and therefore, were restorers (CMS-C) with a genotype of N(S)RfRf. Therefore, the maintainer and restorer sources of resistance may be used in preference in breeding maternal (CMS and their maintainers) and paternal parents (restorers) for resistance to bacterial wilt, respectively, in the hybrid breeding system utilizing cytoplasmic male sterility.

• Journal of Crop Science and Biotechnology
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• v.10 no.4
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• pp.211-222
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• 2007

Selection of the appropriate parents to be used in artificial crosses is one of the main decisions faced by plant breeders that will facilitate the exploitation of maximum genetic variability and production of superior recombinant genotypes. Several techniques have been used in aiding the identification of genotypes with promising and desirable agronomical traits for hybridization. In this way, the objective of the present review is to gather available information for the selection of parents based on different breeding designs and analytical tools showing their similarities and highlighting the main advantages and disadvantages of their use.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.40-45
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• 1978

Degree of dominance for culm length, panicle numbers, flag leaf fwidth and panicle weight showed higher values than the others, and additive protions in variance components were more greater than heterosis protions for many characters. Average gene frequency showed low values for all characters, GCA were more greater than SCA, and the effects of GCA and SCA were differ from parents, crosses, generation and characters.

• Journal of Ginseng Research
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• v.9 no.2
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• pp.264-269
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• 1985

The inheritance of violet and green stems was examined in F1 F2 of violetstem variant x yellow-berry variant in Panax ginseng C. A. Meyer, and the characters of F1 and F2 plants were investigated. From these results, it was shown that most of the characters of F1 and F2 plants were simillar to the female plants. However, reciprocal crosses between violet and green stems yielded progeny of violet-stem variant. Thus the cross V♀x♂Y gave all violet-stem seedlings, and the cross Y♂ x Y♀ gave all violet-stem seedlings. And all of the crosses segregated in F2 in a ratio of 3 violet to 1 green.

• Journal of Plant Biology
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• v.26 no.3
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• pp.141-150
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• 1983

Antithamnion sparsum Tokida isolated from the southern and western coasts of Korea was investigated in culture, comparing the morphological character with A. defectum Kylin from the Pacific North America. A. sparsum basically showed a Polysiphonia-type life history. However, it sometimes exhibited a monoecious reproducton and the carpospores released from the cystocarp by self-fertilization unexpectedly developed into the plants bearing spermatangia alone. These male plants were not functional up to 60 days culture. The results of intraspecific crosses between populations of A. sparsum were positive and the hybrid carpospores gave rise to normal tetrasporophytes. On the other hand, theinterspecific crosses between A. sparsum and A. defectum were successful partly, evidenced by the gonimoblast development and the release of carpospores in case of A. sparsum (male)$\times$A. defectum (female), but not in case of A. sparsum (female)$\times$A. defectum (male). Thus, the both species were still under the speciation.

• Korean Journal of Plant Resources
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• v.3 no.2
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• pp.123-128
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• 1990

In every reciprocal crosses of self pollination, interspecific pollination through ordinary stigma pollination of L. longiflorum and $L.{\;}{\times}{\;}elegans$, pollen vigorously germinated in stigma, and pollen tube was growing. But, 5 days after pollination, pollen tube stopping their growth in the same style as was observed in the cross of self pollination and interspecific pollination. Intrastylar pollination of $L.{\;}{\times}{\;}elegans$ and L. longiflorum passed stylar cannal through the basal part of styles. But, pollen tube that was growing to the ovule of the ovary was extremely small. In morphogical observation of ovary 10 days after pollination, it was observed, that every reciprocal crosses of L. longiflorum ${\times}$ L. ${\times}$ elegans was fertilized through intrastylar pollination, so that this technique was used to overcome cross incompatibilities.lities.