• Korean Journal of Weed Science
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• v.30 no.2
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• pp.68-83
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• 2010

Weedy rice (Oryza sativa L.) occurred sympatrically with other weeds and the rice crop in Malaysian rice granaries. We conducted field surveys in 2006-2008 seasons in 7 farm blocks of Selangor's North West Project, Malaysia to enlist the new biotypes of weedy rice (NBWR) and assess their spatio-temporal pattern of distribution based on quantitative and dispersion indices. No less than 16 accessions of NBWR were identified based on their special traits, viz. panicle type, pericarp colour, presence or absence of awn, seed type and degree of grain shattering. The NBWR accessions exhibited a combination of morphological traits from open panicle, grain with awns, red pericarp, short grain type, and degrees of grain shattering. Others mimic commercial rices with close panicle, awnless grains, white pericarp, long or short grain-type. Invariably, the NBWRs mimic and stand as tall as cultivated rice namely MR219, MR220, or MR235 and these NBWR accessions stand among equals morphologically vis-a-vis the commercial rice varieties. Most accessions displayed varying degrees of grain shattering in excess of 50%, except Acc9 and Acc12. The seasonal dynamics of on the prevalence of dominant NBWR accessions were also displaying significant differences among farm blocks. While Bagan Terap farm block, for example, did not record any measurable changes in the dominant NBWR accessions over seasons, the Sungai Leman farm block recorded measurable season-mediated changes in the dominant NBWR accessions. Sungai Leman started with NBWR Acc3, Acc4, Acc5, Acc7, Acc8, and Acc12 in season 1 of 2006/2007, but no measurable records of Acc3 and Acc5 were shown in season 2 of 2007. In season 3 of 2007/2008, only Acc8 and Acc12 prevailed in the farm block. In Sawah Sempadan farm block, season 3 of 2007/2008 showed much reduced prevalence of NBWRs leaving only Acc8 and Acc12. Most accessions registered clump or under-dispersed spatial distribution pattern based on quantitative indices: variance-to-mean ratio (VMR) and Lloyd's patchiness values. The dynamics on the extent of infestation and prevalence of dominant NBWR accessions registered both season- and farm-block mediated differences. Most accessions showed VMR >1 thus indicative of having a clump or clustered spatial distribution, as exemplified by Acc3, Acc4, Acc7, Acc8 and Acc12 in all farm blocks throughout three seasons. Some accessions have either random or uniform distribution in a few farm blocks. The Acc8 has the highest population counts based on important value index, followed by Acc12, and both were the most dominant accession while Sawah Sempadan was the worst farm block infested by NBWR compared to other farm blocks. These results were discussed in relation with the current agronomic and weed management practices, water availability and extension services in the granary.

• Molecules and Cells
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• v.25 no.3
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• pp.407-416
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• 2008

Thirteen near-isogenic lines (NILs) of japonica rice were developed via a backcross method using the recurrent parent Chucheong, which is of good eating quality but is susceptible to Magnaporthe grisea, and three blast resistant japonica donors, Seolak, Daeseong and Bongkwang. The agro-morphological traits of these NILs, such as heading date, culm length, and panicle length, were similar to those of Chucheong. In a genome-wide scan using 158 SSR markers, chromosome segments of Chucheong were identified in most polymorphic regions of the 13 NIL plants, and only a few chromosome segments were found to have been substituted by donor alleles. The genetic similarities of the 13 NILs to the recurrent parent Chucheong averaged 0.961, with a range of 0.932-0.984. Analysis of 13 major blast resistance (R) genes in these lines using specific DNA markers showed that each NIL appeared to contain some combination of the four R genes, Pib, Pii, Pik-m and Pita-2, with the first three genes being present in each line. Screening of nine M. grisea isolates revealed that one NIL M7 was resistant to all nine isolates; the remaining NILs were each resistant to between three and seven isolates, except for NIL M106, which was resistant to only two isolates. In a blast nursery experiment, all the NILs proved to be more resistant than Chucheong. These newly developed NILs have potential as commercial rice varieties because of their increased resistance to M. grisea combined with the desirable agronomic traits of Chucheong. They also provide material for studying the genetic basis of blast resistance.

• Korean journal of applied entomology
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• v.59 no.3
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• pp.209-215
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• 2020

Debates over the ecological and public health impacts of aerial pesticide sprays are increasing. This is particularly true for controlling Monochamus beetles, which are vector insects of pinewood nematodes. In 2017, adult female orb-web spiders, Trichonephila clavata, were sampled from pine forests in Yangsan-si, Gyeongsangnam-do, Korea, where the aerial pesticide spray, fenitrothion or thiacloprid, was used for several decades. The biological traits of the spiders (body weight, body length, carapace width, and total hind leg length) were compared among treatment sites (no-spray, sprayed three times, and sprayed five times), and differences were observed. The body length, carapace width, and total hind leg length of the spiders in the sprayed areas were significantly shorter than in the no-spray area, but there were no differences between the area sprayed three or five times. These results indicate that repeated exposures to an aerial pesticide spray can alter morphological parameters, which influences population-level fitness. Future studies should monitor the spider long-term responses to pesticides (a direct effect) and prey availability (an indirect effect).

• FLOWER RESEARCH JOURNAL
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• v.19 no.4
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• pp.269-273
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• 2011

This study was conducted to investigate the resistance to abiotic stress in the progeny obtained by a cross between NDPK2-transgenic line (NDPK2-7-1) and MnSOD (SOD2) transgenic line (SOD2-2-1-1-35) to develop transgenic petunia highly resistant to environmental stress. At the treatment of 100 and $200{\mu}M$ methyl viologene (MV), the progeny was significantly less damaged than its parental plants (SOD2- or NDPK2-transgenic lines) as well as non-transgenic plants, implying its resistance to oxidative stress enhanced than SOD2- or NDPK2-transgenic plants. In an expression of 11 quantitative traits, the progeny remained similar to control plants, although it infrequently displayed slightly longer or wider than non-transgenic control plants. In the color and shape of flowers, there was no significant difference between the progeny and its parents or non-transgenic control.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.149-155
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• 2019

This study aims to provide basic data for investigating the phenotypic traits and growth characteristics of Korean native black goats. The Jangsu and Tongyoung strains were shown to have black hair, while the Dangjin strain was shown to have black or dark brown long hair. Only the Tongyeong strain was found to have no wattle and one goat each from the females and males of the Dangjin strain was found to have no horns. The lengths of the ears and tails were similar for the female and male goats, while the lengths of horns and beards were longer in the male goats. The birth weight was 2 kg on average, with that of male goats tending to be slightly heavier than that of the females. Weights at the weaning period were found to be slightly heavier for the males. Also, at 12 months, the weights of the male goats by strain were shown to be heavier than that of the females. The body length and depth by strain were found to be higher for the male goats, while no differences in the chest width and girth between the strains or gender were found. These findings are expected to be used as a basis for differentiating between native and crossbred Korean black goat strains and for improving Korean native black goats.

• Korean Journal of Medicinal Crop Science
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• v.7 no.2
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• pp.138-142
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• 1999

Chinese foxglove (Rehmannia glutinosa) is receiving much attention as one of the principal medicinal crops and the demand for crude drug expands rapidly. This study was conducted to obtain the basic agronomic characteristics and cultivation information of Chinese foxglove. Morphological traits of several Chinese foxglove and their plant growth and yield were investigated under different environmental conditions. The tested lines exhibited clear morphological differences in leaves and roots representing their origins. Rapid root growth and weight increasement occurred in the middle of July. Optimum daylength and temperature conditions were investigated for the adequate plant growth of Chinese foxglove. Root growth was enhanced at $23/18^{\circ}C$ (day/night) with 13 hours daylength condition. Appropriate soil moisture and soil texture were $60{\sim}70%$ and loam soil, respectively.

• Parasites, Hosts and Diseases
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• v.53 no.3
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• pp.361-364
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• 2015

Gynandromorphic ticks are extremely rare, and often attract parasitologists' attention. During our examination of tick specimens, an engorged gynandromorph of Hyalomma asiaticum was noticed. This is the first record of gynandromorphic ticks from China. In this study, several important morphological structures of normal and gynandromorphic H. asiaticum were analyzed. Comparing to the normal H. asiaticum, the gynandromorphic specimen was a typical bipartite protogynander. Its right side showed normal female characteristics, whereas the left side had normal male traits. Different from other gynandromorphic ticks containing 1 anus, this tick reported here had 2 complete anuses, and the anus of the male part had a single adanal plate.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.267-273
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• 2013

In this study, 241 zoysiagrasses (Zoysia spp.) accessions naturally growing in South Korea were collected in order to investigate the seed morphological traits. One of the goals of this study was to identify the morphological characteristics and variations of zoysiagrass seed. For the 241 zoysiagrasses accessions collected, a total of 41% (99 accessions) was interspecific hybrid zoysia, which showed various types of seed variations different from zoysiagrass species. Most of these hybrids zoysiagrasses were classified into Z. sinica type and Z. japonica type. Group I and II included Z. sinica type, this group showed 30.1 and 17.5 in number of seed per spike and 4.6 and 5.2 mm in seed length. Group III and IV included Z. japonica type, this group showed 59.2 and 45.8 in number of seed per spike and 3.3 and 3.4 mm in seed length. There is a need for additional research on growth characteristics and the molecular level for the interspecific hybridization which confirmed that genetic variation from level of gene flow between the species.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.798-806
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• 2013

Precise, fast, and cost-effective identification of crop cultivars is essential for plant breeder's rights. Traditional methods for identification of persimmon cultivars are based on the evaluation of sets of morphological characteristics. However, it is difficult to distinguish closely related cultivars using only morphological traits. This study was conducted to develop DNA markers for identification of the 32 persimmon cultivars in Korea and Japan. A total of 309 randomly amplified polymorphic DNA (RAPD) markers were identified using 40 different random primers. Various number of polymorphic bands ranged from 4 (OPP-08) to 14 (UBC159) were detected with an average of 7.7. Resulting 57 RAPD fragments were selected, and their sequences were determined for developing sequence characterized amplified region (SCAR) markers. As a result, 15 of 57 RAPD fragments were successfully converted to SCAR markers. Single polymorphic bands of the same size as or smaller than the RAPD fragments were amplified depending on SCAR markers. Among these markers, a combination of eight SCAR markers (PS225_200, PSN05_420, PSF13_523, PSN11_540, PS372_567, PS485_569, PSP08_635, and PS631_735) provided sufficient polymorphisms to identify 32 persimmon cultivars. These newly developed markers will be a fast and reliable tool to identify persimmon cultivars.

• Korean Journal of Plant Resources
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• v.20 no.4
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• pp.336-341
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• 2007

This study was carried out to investigate geographic variation in needle characteristics of Pinus densiflora, one of the most economically important tree species in Korea. Needles were collected from 35 natural populations and their morphological and anatomical characteristics were studied. ANOVA showed statistically significant differences among populations as well as among individuals within populations in needle length, needle width, number of stomata row, density of stomata in $0.25mm^{2}$, number of serrations in 0.5mm, and number of resin ducts. In all these traits, variance components among individuals within populations were larger than those among populations. The density of stomata in $0.25mm^{2}$ increased as the latitudes and elevations of the populations increased, while the number of serrations in 0.5mm decreased as the decrease of latitudes and elevations. The number of resin ducts was higher in inland populations than in coastal populations. The resin duct index appeared to be higher in western populations than in eastern populations. Cluster analysis based on morphological characteristics divided populations into three groups. The third group was composed of populations selected from the Taebaek mountains. The number of serrations in 0.5mm of this group was lower than that of other two groups, while the density of stomata in $0.25mm^{2}$ was higher.