• The Plant Pathology Journal
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• v.18 no.5
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• pp.266-270
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• 2002

Inbred lines of Chinese cabbage KU-101 (resistant line against Plasmodiophora brassicae race race 6) and CS-113 (susceptible line) were crossed and their progeny lines F$_1$, BC$_1$F$_1$, F$_2$, and F$_3$ were produced for the construction of the genetic linkage map of R brassicae race 6-resistant Brassica campestris ssp. pekinensis genome. Restriction fragment length polymorphism (RFLP) was applied to compare between parents and their f$_2$ progenies with a total of 192 probes and 5 restriction enzymes. The constructed RFLP map covered 1,104 cM with a mean distance between genetic marker of 8.0 cM, and produced 10 linkage groups having 121 genetic loci. The loci of P. brassicae race 6 (CR6)-resistant Brassica genome were determined by interval mapping of quan-titative trait loci (QTL), which resulted from bioassay using the same race of the fungi in P3 population. Resistant loci were estimated in numbers 1 (Gl) and 3 (G3) linkage groups. In the regression test, Gl had a value of4.8 logarithm of odd (LOD) score, while C3 had values of 4.2-7.2. Given these results, the location of the CR6-resistant loci within the Brassica genome map can now be addressed.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.230-235
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• 2013

Amaranths (Amaranthus sp.), an endemic American crop, are now grown widely across the world. This study used 14 simple sequence repeat (SSR) markers to analyze the genetic diversity of 74 amaranth accessions from the United States, with eight accessions from Australia as controls. One hundred twenty-two alleles, averaging eight alleles per locus, were observed. The average major allele frequency, expected heterozygosity, and polymorphism information content (PIC) were 0.44, 0.69, and 0.65, respectively. The structure analysis based on genetic distance classified 77 accessions (94%) into three clusters, while five accessions (6%) were admixtures. Among the three clusters, Cluster 3 had the highest allele number and PIC values, while Cluster 2 had the lowest. The lowest FST was between Clusters 1 and 3, indicating that these two clusters have higher gene flow between them compared to the others. This finding was reasonable because Cluster 2 included most of the Australian accessions. These results indicated satisfactory genetic diversity among U.S. amaranths. These findings can be used to design effective breeding programs involving different plant characteristics.

• Research in Plant Disease
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• v.7 no.2
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• pp.69-79
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• 2001

Meloidogyne arenaria race 2 (59%) is widely distributed, followed by M. incognita race 1 (23%), and an unknown race of M. incognita (18 ％) in greenhouses in southern Korea. The key character to distinguish between M. arenaria and M. incognita is excretory pore in female head. When oriental melon, Cucumis melo L., grafted on Shintozoa (Cucurbit maxima x Cu. moschata) is transplanted in February in a plastic tunnel inside a greenhouse infested with M. arenaria, nematodes produced egg masses on roots at 40 days after transplanting and the soil juveniles (J2) population reach maximum in July to 3,817/100 ㎤. Juveniles are distributed relatively uniform over the 180-cm-wide row horizontally and the highest density occurs at 0-25 cm soil depth. For the control of root-knot nematodes, rice rotation, solarization, and soil addition treatments are the most effective (P=0.05); treatments reduce number of J2 over 90% and increase yield two times. Corn retation, fosthiazate, and soil drying treatment are moderately effective, while sesame and green onion rotations are not effective. The relationship between M. arenaria and yield of oriental melon is adequately described by a linear regression model. In the test with wild Cucumis genetic sources introduced from U.S.Dept. of Agriculture (USDA), one of C.heptadactylus, two of C.anguria, two of C. anguria var. longaculeatus, nine of C. metuliferus are resistant to both species of root-knot nematodes.

• Korean Journal of Veterinary Research
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• v.45 no.4
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• pp.601-606
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• 2005

The disease causing colic is the greatest cause of death in the domestic horse population today and accidental deaths as a result of colic leads to decreased productivity and economic losses in the horse breeding industry. Large colon impaction is the most common cause of colic in horses. Horses may ingest sand either by eating from the ground in sandy locations, or because of its inclusion in hay. In certain areas sand impaction is relatively common. The horse (4 year, female) presented with abdominal pain, which was charactered by willing to lie down, pawing, and looking at flank. A month later, the horse died suddenly at sand paddock. Post-mortem examination revealed the sand impaction as a lot of feces, sand and gravels in the right dorsal colon. In addition, there was necrosis and debilitation in mucosal lining of the large colon and rupture site on the right dorsal colon. The purpose of this article is to review sand impaction and emergencies in Thoroughbred horses.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.11-14
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• 1984

The inheritance of scent in rice leaf and its genetic association with base color, hull color and resistance to bacterial leaf blight were studied in F$_2$ population of two rice crosses, P-33-C-19 (scented)/Zhu-Lian-Ai and P-33-C-19/Kataktara DA2. The scent was identified by leaf analysis at tillering stage. The scented and non-scented plants segregated in the ratio of 1scented: 3non-scented showing that a recessive gene responsible for the expression of scentedness. The scentedness was independently segregated with base color. hull color and resistance to bacterial leaf blight.

• Korean Journal of Veterinary Service
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• v.33 no.2
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• pp.113-119
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• 2010

Brucellosis is a major zoonosis caused by Gram negative facultative intracellular bacterial organisms of the genus Brucella that are pathogenic for a wide variety of animals and human beings. Because of its economic impact on animal health and the risk to the human population,most countries have a brucellosis control program. Brucellosis is also an economically important andprevalent disease in Bangladesh. The accurate and prompt diagnosis is very important in controlling and eradicating of the disease in animals. The present study was undertaken to determine the seroprevalence of brucellosis in cattle in Mymensingh and Patuakhali district of Bangladesh. A total of 120 serum samples were collected from the two districts along with a questionnaire related to the epidemiology of the disease. The sampleswere screened by using slow agglutination test and conformed by indirect enzyme linked immunosorbent assay. The overall seroprevalence of brucellosis in cattle was 5% and it was observed that, a higher prevalence of Brucella was found in female than male, through natural breeding than artificial insemination (AI) and animal above 4 years old are highly susceptible than younger ones. Higher prevalence was found in aborted animals in comparison with non aborted animal. Finally, the study revealed that the female animal has more susceptible to brucellosis and healthy semen should be used for AI.

• Journal of Forest and Environmental Science
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• v.32 no.3
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• pp.311-322
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• 2016

Since forest trees form the basis of forest ecosystem, their prolong subsistence is crucial for various flora and fauna. The foremost challenges to sustain the forest ecosystem comprise of the declining forest tree population accompanied with structural changes due to afforestation and exploitation of forest area, environment changes, pests, pollution, and introgressive hybridization. For ex situ conservation approach, in vitro techniques encompass basic role for conserving tree genetic resources, predominantly where natural propagules like recalcitrant seed might not be appropriate for long-term conservation. The practice includes restricted growth techniques, conventional micropropagation, production and storage of synthetic seeds, and cryopreservation. Even though these practices have been applied chiefly to herbaceous species, but recently, woody species were also focused upon. Key conceptions, challenges and techniques for forest tree seed conservation are discussed briefly in this review with special emphasis on some successful cryopreservation approaches for long-term storage.

• Journal of Crop Science and Biotechnology
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• v.11 no.3
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• pp.163-170
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• 2008

The detection, characterization and use of quantitative traits loci, QTL, have significant potential to improve the efficiency of selective breeding of species. Therefore, a population with 59 advanced backcross lines($BC_2F_5$), derived from a cross between IR64 and Tarome molaei, were studied in Tonekabon Rice Research Station of Iran in order to map QTLs for panicle length, number of grain per panicle, and panicle grain sterility in rice. The parental screening wtih 235 SSR markers in agarose and polyacrylamide gels revealed 114 markers with clear polymorphic bands. To search for QTLs associated with panicle length, number of grain per panicle, and panicle grain sterility, we constructed a genetic linkage map using 114 microsatellite markers. Positive and negative transgressive segregations were observed in $BC_2F_5$ lines for all traits. Using multiple interval mapping(MIM), a total of 20 putative QTLs were detected, of which eight were for panicle length, three for number of grains, and nine for panicle grain sterility. The maximum number of QTLs were mapped on chromosomes 1 and 2 with eight QTLs. These QTL markers could possible be utilized for marker-assisted selection.

• Journal of Life Science
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• v.7 no.4
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• pp.358-360
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• 1997

Soybean [Glycine max (L.) Merr.] seed size is a important yield component and is a primary consideration in the development of cultivars for specialty markets. Our objective was to examine the consistency of QTLs for seed size across generations. A 68-plant F$_{2} segregation population derived from a mating between Marcury (small seed) and PI 467.468 (large seed) was evaluated with RAPD markers. In the F$_{2} plant generation (i.e. F$_{3} seed), three markers, OPL09a, OPM)7a, and OPAC12 were significantly (P<0.01) associated with seed size QTLs. In the F$_{2} ; F$_{3} generation (i.e., F$_{4} seed), four markers, OPA092, OPG19, OPL09b, and OPP11 were significantly (P<0.01) associated with seed size QTLs. Just two markers, OPL09a, and OPL09b were significantly (P<0.05) associated with seed size QTLs in both generations. The consistency of QTLs across generations indicates that marker-assisted selection for seed size is possible in a soybean breeding program.

• The Plant Pathology Journal
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• v.35 no.1
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• pp.1-10
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• 2019

Wheat blast occurred in Bangladesh for the first time in Asia in 2016. It is caused by a fungal pathogen, Magnaporthe oryzae Triticum (MoT) pathotype. In this review, we focused on the current status of the wheat blast in regard to host, pathogen, and environment. Despite the many efforts to control the disease, it expanded to neighboring regions including India, the world's second largest wheat producer. However, the disease occurrence has definitely decreased in quantity, because of many farmers chose to grow alternate crops according to the government's directions. Bangladesh government planned to introduce blast resistant cultivars but knowledges about genetics of resistance is limited. The genome analyses of the pathogen population revealed that the isolates caused wheat blast in Bangladesh are genetically close to a South American lineage of Magnaporthe oryzae. Understanding the genomes of virulent strains would be important to find target resistance genes for wheat breeding. Although the drier winter weather in Bangladesh was not favorable for development of wheat blast before, recent global warming and climate change are posing an increasing risk of disease development. Bangladesh outbreak in 2016 was likely to be facilitated by an extraordinary warm and humid weather in the affected districts before the harvest season. Coordinated international collaboration and steady financial supports are needed to mitigate the fearsome wheat blast in South Asia before it becomes a catastrophe.