• Korean journal of applied entomology
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• v.32 no.2
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• pp.193-199
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• 1993

The morphological relationship between Drosophila melanogaster and D. simulans, and their hybrids were investigated using comparisons of internal reproductive organs. male sex comb tooth number and male genital discs. InterspecIfic hybrids of all crosses were completely sterile, and had rudImentary gonads. Dysgenic ovaries and testes were morphologically similar to those of gonadal dysgenesis stenlity associated with the PM system in D. melal1ogaster. The mean number of sex comb tooth in D. melrmogaster, D. simulans and their male hybrids were 10.73, 8.35 and 9.97, respectively. The general aspects of the genital disc of the malo hybrid were a mosaic-like structure between D. melanogaster and D. simulans.

• Journal of Crop Science and Biotechnology
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• v.11 no.4
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• pp.257-262
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• 2008

Genetic diversity of cultivated wheat is narrowing down and is increasingly becoming non-complacent in tackling new pathogenic races and adverse environmental situations. Wild relatives of wheat are rich repositories of beneficial genes that are capable of defying adverse situations. However, these wild species are not readily crossable with cultivated ones. The present study attempted to cross three wild wheat species as females with three cultivated species of varying ploidy to understand the intricate behaviour of hybrids in relation to cytology, morphology, and molecular recombination. Post-fertilization barriers caused hybrid recovery in wild species in contrast to cultivated species. Triticum monococcum did not produce hybrids in any of the crosses. Various degrees of chromosome anomalies and hybrid sterility were seen with hybrids of T. timopheevi and T. sphaerococcum. Cytoplasmic factors were suspected to add more to the abnormality. G genome from T. timopheevi could enhance more pairing between Band D of cultivated species. Precocity of certain chromosomes in laggard formation was evident, pointing towards evolutionary self balance of the genomes which prevented homeologous pairing. They are eliminated in hybrids. Molecular diversity clearly corroborated with genetic proximity of the species, which distinguished themselves by maintaining the genome homeology.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.288-294
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• 1994

Seedling vigor of introgressive hybrids between birdsfoot refoil 'MO-20"(Lotus corniculatus) used as the maternal parent and tetraploid(2n=4x=24)accession PI302921 narrowleaf trefoil(Lotus corniculatus L.), and parents were compared in terms of dry matter accumulation , net photosynthetic rate, dark respiration rate, and growth analysis. The hybrids showed better seedling vigor than PI302921 as they had lower dark respiration rate and higher relative growth rate (RGR) than PI302921. Hybrids grew faster than MO-20, but there was not significant difference between them. Net photosynthesis per unit area increased during three weeks after emergence without difference among the entries, then decreased sharply with leaf age and shading marking much differences among entries Dark respiration rate was very high just after emergence, after which it decreased rapidly until it reached a stable level at 1 week through 3 weeks of age, and then dropped again. In general, dark respiration, photosynthesis, and seedling growth of the hybrid was similar to those if MO-20. Although there are some reports about interspecific hybrids of Lotus species, it still remains as a new area for genetic improvement of seedling vigor of L. corniculatus.atus.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.55-63
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• 2011

This study was carried out to develop new cultivars of Hibiscus species from crosses between introduced interspecific hybrids and cultivars in Hibiscus species. Fruit setting of interspecific crosses of Hibiscus strains was less than 10% and the number of seeds in the fruit was also in low level. Three individuals of specific flower and leaf characteristics were selected from crosses between introduced interspecific hybrid, 'Fujimusme'(♀), and H. syriacus 'Namwon'(♂) in 2004. A new strain, Hibiscus ${\times}$ 'W-26', was selected from the crossing of interspecific hybrid, 'Fujimusme'(♀), and H. syriacus 'Namwon'(♂), which had white flower and narrow separated petal. Hibiscus ${\times}$ 'WRB-2' was selected from the crossing of interspecific hybrid, 'Fujimusme'(♀), and H. syriacus 'Namwon'(♂), which had white flower and blue eye spot. Hibiscus ${\times}$ 'R-141' was selected from crosses between introduced interspecific hybrid, 'Shichisai'(♀) and H. syriacus 'Namwon'(♂), which had large flowers over 13 cm diameter and revealed tall tree type. Hibiscus ${\times}$ 'R-142' was selected from the crossing of interspecific hybrid, 'Shichisai'(♀), and H. syriacus 'Namwon'(♂), which had large flowers over 13 cm diameter and revealed tall tree type. The characteristics were succeded after grafting. Flower of 'R-142' had reddish violet color with red eye spot, whereas its parent had blue and purple flowers.

• Horticultural Science & Technology
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• v.33 no.3
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• pp.396-402
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• 2015

This study identified a new male-sterile germplasm of Chinese jujube, named male-sterile No. 2 (JMS2), and achieved controlled hybridization using that germplasm as the female parent. The anthers of JMS2 before flower bud opening became shrunken, dingy yellow and much smaller than normal ones, and they changed to brown after anthesis. No pollen was observed in anthers of JMS2 and its male-sterile trait remained stable over different years. A total of 1,642 fruits were obtained from ten intra- and interspecific cross combinations via controlled hybridization from 2008 to 2012 using JMS2 as the female parent. Of those, 27.3% produced seeds, on average (0-72.6%). The rate of fruit with seed (RFS) was significantly different between cross combinations or years. Compared to other cross combinations, the RFS in the combination of JMS2 ${\times}$ 'Xingguang' (a Chinese jujube cultivar with high resistance to jujube witches' broom disease) and JMS2 ${\times}$ 'Xing16' (a sour jujube genotype) remained high in different years and reached means of 48.7 and 58.1%, respectively. Finally, 150 plantlets were regenerated from immature embryos, and 51 of them were randomly selected and identified to be authentic hybrids using amplified fragment length polymorphism (AFLP) markers. This is the first report of hybrids obtained from a cross between Chinese jujube and sour jujube.

• Journal of Plant Biotechnology
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• v.31 no.2
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• pp.103-108
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• 2004

This study was carried out to develop the efficient methods for the subsequent progeny of intersectional hybrid between Oriental and Asiatic lily hybrids. The pollen fertility and germination ability of 3 different allotetraploids (OAOA) after somatic chromosome doubling was ranged from 0 to 80 percent on artificial pollen germination medium. The number of BC$_1$ progeny using allotetraploid of F$_1$ OA-hybrid as male and female parent was different. The efficiency of BC$_1$ progeny production was increased when F$_1$OA-hybrids was used as male rather than as female parent. And in back crosses of F$_1$ OA-hybrids with the Asiatic and Oriental hybrids, Asiatic hybrids showed higher efficiency on BC$_1$ progeny production. The ploidy level between 2x or 4x Asiatic hybrid and allotetraploid F$_1$ OA-hybrid was determined and showed higher progeny production in 2x-4x crosses rather than 4x-4x.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.2
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• pp.123-127
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• 1988

Even though grass species are one of major importance in livestock industry, the response of intergeneric hybridization of Lolium and Festuca and interspecific hybridization of Lolium m.X Lolium p. to Korean climatic condition has not been adequately documented. This reasearch was conducted to examine the growth characteristics and dry matter yield of Festulolium, cv. Felopa and C-Stamm N 66 and hybrid ryegrass, cv. Maja and Tetilelite. 1. The early growth of Italian ryegrass was better than that of hybrid ryegrass and Festulolium. The plant length and height of Italian ryegrass were longer/taller than those of hybrid ryegrass and Festulolium, but the number of tillers of Italian ryegrass was less than that of hybrid ryegrass and Festulolium. 2. Festuloliu and hybrid ryegrass were more tolerant than Italian ryegrass to winter killing, 70-80% of tillers was survived. 3. After wintering, early spring growth of hybrid ryegrass and Festulolium were better than that of Italian ryegrass. Dry matter yield of hybrid ryegrass and Festulolium were more than that of Italian ryegrass. 4. Spikes of hybrid ryegrass and Festulolium (C-Stamm N66) were more than those of Italian ryegrass. Seed yield per $m^2$ of hybrid ryegrass and Italian ryegrass were almost same, but that of Festuloliu was lower.

• Journal of Plant Biotechnology
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• v.29 no.3
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• pp.199-207
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• 2002

The tropane alkaloids hyoscyamine (its racemic form being atropine) and scopolamine are used medicinally as anticholinergic agents that act on the parasympathetic nerve system. Because they differ in their actions on the central nervous system, currently there is a 10-fold higher commercial demand for scopolamine, in the N-butylbromide form, than there is for hyoscyamine and atropine combined. Several solanaceous species have been used as the commercial sources of these alkaloids, but the scopolamine contents in these plants often are much lower than those of hyoscyamine. For this reason there has been long-standing interest in increasing the scopolamine contents of cultivated medicinal plants. Naturally occurring and artificial interspecific hybrids of Duboisia have high scopolamine contents and are cultivated as a commercial source of scopolamine in Australia and other countries. Anther culture combined with conventional interspecific hybridization also has been used to breed high scopolamine-containing plants in the genera Datura and Hyoscyamus, but without much success. The use of recombinant DNA technology for the manipulation of metabolic processes in cells promises to provide important contributions to basic science, agriculture, and medicine. In this review, I introduce on the enzymes and genes involved in tropane alkaloid biosynthesis and current progress in metabolic engineering approaches for tropane alkaloid, especially scopolamine, production.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.408-417
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• 2019

This study was conducted to identify taxonomic differences in the characteristics of Rhodeus uyekii and Rhodeus ocellatus during their initial life history via an interspecific hybridization experiment. Hybrids were compared to their parent species, and the findings were used to inform developmental research in commercially useful aquarium fish. The hatching rates of the cross-bred eggs were 75.9% for cross UO (R. uyekii ♀${\times}$R. ocellatus♂) and 71.9% for cross OU (R. ocellatus♀${\times}$R. uyekii♂), which did not differ greatly from the hatching rates of the normal cross-bred group. Backcross experiments resulted in 100% egg mortality during development. Newly hatched larvae of the original hybrid crosses were similar to those of the maternal line, and the color of the egg yolk was similar to that of the paternal line; therefore, the respective traits of the interspecific parents were identifiable within the cross-bred offspring.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.378-385
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• 1994

Interspecific somatic hybrids were obtained by protoplast fusion between Pleurotus ostreatus and Pleurotus sajor-caju. The fusion products between incompatible strains did not form clamp connections. Fruiting body of the clampless fusants was induced by light-dark cycle on saw-dust-rice bran substrate in glass bottles. Out of them, seven somatic hybrids produced fruiting bodies of intermediate morphology of the two species. Light and low temperature were the initiating factors for the development of clamped hyphae from the clampless mycelial colonies. All of these basidiocarps had clamp connections. Eight fusants from the six crosses were analysed with the segregation of genetic characters by random spore isolates. In the three combinations, unexpected alleles were shown. Somatic hybrid between P188 (P. ostreatus 2-1 + P. sajor-caju 2-53) and P. florida 2-3 by triple cross produced fruiting bodies similar to those of fusant between P. ostreatus and P. florida. All the genetic charaters from the three strains were shown to segregate and recombine.