• The Plant Pathology Journal
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• v.19 no.3
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• pp.143-147
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• 2003

Sensitivity of Phytophthora infestans isolates to fungicides metalaxyl and ethaboxam in Korea was examined with 260 isolates for 3 years (9 isolates in 2000,93 isolates in 2001, and 158 isolates in 2002). Both Al and A2 mating types were found from the isolates collected for 3 years. Al mating type was dominant in the population with 8 isolates (88.9%) in 2000, 84 isolates (89.4%) in 2001, and 138 isolates (87.3%) in 2002. Only some isolates from diseased tomatoes in Buyergun and diseased potatoes in Pyeongchanggun were of the A2 mating type. As for metalaxyl sensitivity, 77.0% of the isolates were moderately resistant with 8 isolates (88.9%) in 2000, 73 isolates (77.7%) in 2001, and 120 isolates (75.9%) in 2002. Meanwhile, those found resistant were 1 isolate (11.1%) in 2000, 16 isolates (17.0%) in 2001, and 33 isolates (20.9%) in 2002. Only 5 isolates (3.2%) were sensitive to metalaxyl in 2002. There was no significant difference in the sensitivity among years. As for ethaboxam, no isolate was able to grow at 5.0 $\mu\textrm{g}$ /ml, and only four isolates (1.5 %) grew at 1.0 $\mu\textrm{g}$ /ml with heavy retardation compared with the untreated control. Based on these 3-year results, the minimum inhibitory concentration (MIC) of ethaboxam to p. infestans was determined to be 0.2-1.0 $\mu\textrm{g}$ /ml. Results indicate that resistance development by p. infestans to ethaboxam is not likely to occur in the natural condition. furthermore, there was no indication of cross resistance between metalaxyl and ethaboxam because all the isolates, regardless of classification for their sensitivity to metalaxyl, were not able to grow at 5.0 $\mu\textrm{g}$ /ml of ethaboxam.

• Journal of Mushroom
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• v.2 no.1
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• pp.38-41
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• 2004

Compatibility test of the 115 world-wide collections of Ganoderma strains including 61 of Korean origin, were performed by di-mon mating with tester strains G. lucidum G001-1 ($A_1B_1$) and G. tsugae 1109-16 ($A_1B_1$). Unexpected results were found in that 75 strains, formerly considered to be G. lucidum exhibited clamp connections in mating with the tester 1109-16. This observation suggests that these strains require further examination prior to taxonomic classification. Interestingly, this compatibility could be confirmed more easily by the finding of distinct confrontation line between two strains on plate.

• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.1
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• pp.167-174
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• 2011

The large bumblebee $Bombus$ $terrestris$, indigenous to Europe and adjacent areas and used extensively for high-value crop pollination, has been artificially introduced to several parts of the world. Here we show the occurrence of interspecific hybridization between the bumblebee species $B.$ $hypocrita$ $sapporoensia$ and $B.$ $terrestris$ under laboratory conditions. The mating and oviposition percentages resulting from the interspecific hybridization of a $B.$ $terrestris$ queen with a $B.$ $h.$ $sapporoensis$ male were higher than those resulting from the intraspecific mating of $B.$ $h.$ $sapporoensis$. Furthermore, a competitive copulation experiment indicated that the mating of $B.$ $h.$ $sapporoensis$ males with $B.$ $terrestris$ queens was 1.2-fold more frequent than the mating of these males with $B.$ $h.$ $sapporoensis$ queens. The interspecific hybridization of a $B.$ $terrestris$ queen with a $B.$ $h.$ $sapporoensis$ male produced either $B.$ $terrestris$ workers or the $B.$ $terrestris$ male phenotype, and the hybridization of a $B.$ $h.$ $sapporoensis$ queen with a $B.$ $terrestris$ male produced $B.$ $h.$ $sapporoensis$ males. Our results indicated that interspecific hybridization occurred between $B.$ $h.$ $sapporoensis$ and $B.$ $terrestris$. These results suggest that such hybridization will have a negative competitive impact and will cause genetic contamination of native bumblebees.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.235-240
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• 2006

Efficacies of two commercial mating distruptor (SPLAT$^{(R)}$ and Isomate$^{(R)}$-ROSSO) were evaluated on field overwintering populations of Oriental fruit moth, Grapholita molesta (Busck), in four apple orchards. Based on the monitoring with sex pheromone traps, all the orchards (Youngchun, Kyungsan, Chungsong, and Youngju in Korea) exhibited significant overwintering populations from late April to late May. Both mating disruptors that were applied 10 days before the monitoring period significantly inhibited the male orientation to the monitoring lures, in which SPLAT type was more effective than Isomate type in the disrupting efficacy. The disruption of male orientation was highly correlated with the reduction in the early leaf damage caused mostly by G. molesta.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.63-71
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• 2012

To assess parameters of mating system in seed orchard, such as outcrossing rates, number of potential pollen contributors, and degree of pollen contamination, seeds, produced in '77 plot of the Japanese red pine (Pinus densiflora S et Z) seed orchard at Anmyeon island, were collected in 2007 and analysed by nSSR and cpSSR markers. Estimates of outcrossing rates ranged from 91.2 to 100% (mean 97.7%) on the basis of the analysis of cpSSR haplotypes and from 81.6 to 100% (mean 95.3%) on the basis of the analysis of nSSR genotypes. By cross checking of both DNA markers, seeds, presumed to be products of self pollination on the basis of single marker, were confirmed as outcrossed seeds, which resulted in cumulative outcrossing rates of 98.9%. On the basis of pooled cpSSR haplotype of each seed, the number of pollen contributors and paternal contribution rates were estimated as 14.8 and 0.512, respectively. In conclusion, considering pretty high level of outcrossing rates observed in a seed orchard, good genetic potential of the seeds, produced in '77 plot of the seed orchard of Japanese red pines at Anmyeon island, may be guaranteed. Investigated results from the analysis of mating system of Japanese red pines in a '77 plot of the seed orchard may also be expected to provide useful information for the management and establishment of the seed orchard of the progressive generation.

• Journal of Korean Institute of Industrial Engineers
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• v.29 no.1
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• pp.49-64
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• 2003

Although assembly sequence planning is an essential task in assembly process planning, it is known as one of the most difficult and time consuming jobs because its complexity is increased geometrically when the number of parts in an assembly is increased. The purpose of this study is to develop a more efficient algorithm for generating assembly sequences automatically. By considering subassemblies, a new heuristic method generates a preferred parallel assembly sequence that can be used in robotic assembly systems. A parallel assembly sequence concept provides a new representation scheme for an assembly in which the assembly sequence precedence information is not required. After an user inputs both the directional mating relation information and the mating condition information, an assembly product is divided into subgroups if the product has cut-vertices. Then, a virtual disassembly process is executed to generate alternate parallel assembly sequences with intermediate assembly stability. Through searching parts relations in the virtual disassembly process, stable subassemblies are extracted from translation-free parts along disassembling directions and this extraction continues until no more subassemblies are existed. Also, the arithmetic mean parallelism formula as a preference criterion is adapted to select the best parallel assembly sequence among others. Finally a preferred parallel assembly sequence is converted to an assembly BOM structure. The results from this study can be utilized for developing CAAPP(Computer-Aided Assembly Process Planning) systems as an efficient assembly sequence planning algorithm.

• Toxicological Research
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• v.12 no.1
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• pp.129-136
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• 1996

A fertility and general reproductive a. bility study was performed in Sparque-Dawley rats intravenously injected with Ginkgo biloba extract (EGb 761), a potential pharmaceutical excipient, at dose levels of 7.5, 15, and 30 mg/kg/day. Male rats were treated with Ginkgo biloba extract (EGb 761)from 14 days before mating until 21 days after delivery. Female rats received extract for 2 months prior to mating. No abnormal signs were noted in mating or fertility of the rats treated with Ginkgo biloba extract (EGb 761). No significant external, visceral, and skeletal anomalies or mental and physical development attributable to treatment was noted in any fetuses examined. The fertility of F1 generation was not affected by the treatment also. It was concluded that Ginkgo biloba extract (EGb 761) has no harmful effect on mating, fertilization, implantation, embryonic development and normal physical development.

• Journal of Forest and Environmental Science
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• v.37 no.4
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• pp.309-314
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• 2021

This study aimed to enhance seed productivity and secure genetic resources for Pinus densiflora for. multicaulis. We analyzed the characteristics of cone and seed generated by control pollination between Pinus densiflora (PD) and Pinus densiflora for. multicaulis (PDM). The highest number of cone scales (63.0) was obtained from the self-pollinated (sp) PDM clone B (PDM-sp-B), whereas the lowest number of cone scales (44.7) was obtained from two combinations designated as PDM-A×PD-075 and PDM-A×PD-0111. Both female parents of the hybrids were PDM-A. The highest seed production capacity (80.8) was obtained from the open-pollinated (op) PDM clone B (PDM-op-B). The seed potentials of PDM-B×PD-0111, PDM-op-A, and PDM-sp-B were 67.4, 66.5, and 63.1, respectively. The highest number of fertile scales (41.5) was obtained from PDM-op-B, and the lowest number of fertile scales (28.8) was obtained from PDM-A×PD-075. The total number of aborted ovules and 1st aborted ovules was not statistically significant in the mating design. The cross combination of PDM-B×PD-0111 had the highest number (34.8) of filled seeds and the lowest number of 2nd aborted ovules (5.2) and empty seeds (9). PDM-op-B had the highest number of developed seeds (47.6), although the number of empty seeds was the highest (41.2). Therefore, we conclude that the mating design of PDM-B×PD-0111 is useful for future breeding programs to improve seed yield of PDM. Our results showed that there was a strong correlation between the following two parameter pairs: number of scales and number of fertile scales, and the number of fertility scales and seeds potential (r=0.89 and r=0.84, respectively; both p<0.01).

• Mycobiology
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• v.51 no.6
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• pp.452-462
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• 2023

Opportunistic infections due to Cryptococcus neoformans and C. gattii species complexes continue to rise unabated among HIV/AIDS patients, despite improved antifungal therapies. Here, we collected a total of 20 environmental and 25 presumptive clinical cryptococcal isolates from cerebrospinal fluid (CSF) samples of 175 patients enrolled in an ongoing clinical trial Ambition 1 Project (Botswana-Harvard Partnership). Identity confirmation of the isolates was done using MALDI-TOF MS and PCR. We describe the diversity of the isolates by PCR fingerprinting and sequencing (Oxford Nanopore Technology) of the intergenic spacer region. Mating types of the isolates were determined by amplification of the MAT locus. We report an unusual prevalence of 42.1% of C. neoformans × C. deneoformans hybrids Serotype AD (n = 16), followed by 39.5% of C. neoformans Serotype A (n = 15), 5.3% of C. deneoformans, Serotype D (n = 2), 7.9% of C. gattii (n = 3), and 5.3% of C. tetragattii (n = 2) in 38 representative isolates that have been characterized. Mating type-specific PCR performed on 38 representative environmental and clinical isolates revealed that 16 (42.1%) were MATa/MAT𝛼 hybrids, 17 (44.7%) were MAT𝛼, and five (13.2%) possessed MATa mating type. We used conventional and NGS platforms to demonstrate a potential link between environmental and clinical isolates and lay a foundation to further describe mating patterns/history in Botswana.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.4
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• pp.448-458
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• 2024

The direction of eye movement in Pleuronectiformes is species-specific. In farmed flounder, deviations in eye direction can reduce marketability. Therefore, we explored the effects of genetic and environmental factors on the direction of eye movements in the starry flounder Platichthys stellatus to address this economic challenge. Four pairs of female and male starry flounder broodstock, with eyes positioned to the right or left, were used in a mating experiment. The experimental groups were established with breeding seawater temperatures set at 10, 14, and 18℃ for the water temperature experiment. Whole-body samples of juveniles were collected to analyze the expression of genes related to eye movement and direction. The mating experiment results showed no significant differences in abnormal eye movement. In the water temperature experiment, the rate of abnormal eye movement was significantly higher at 32.19±1.33% in the 18℃ group than in the 10 and 14℃ groups. Genetic analysis of eye movement related to water temperature revealed that the expression of eye migration genes was significantly higher at 10℃. Moreover, no significant differences were observed in mating experiments. In conclusion, water temperature and not mating affected the eye movement of starry flounder.