• Animal Bioscience
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• v.34 no.9
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• pp.1451-1459
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• 2021

Objective: The objectives of the study were to evaluate reproductive performance and selection response through genetic trend of community-based breeding programs (CBBPs) of Bonga sheep. Methods: Reproduction traits data were collected between 2012 and 2018 from Bonga sheep CBBPs. Phenotypic performance was analyzed using the general linear model procedures of Statistical Analysis System. Genetic parameters were estimated by univariate animal model for age at first lambing (AFL) and repeatability models for lambing interval (LI), litter size (LS), and annual reproductive rate (ARR) traits using restricted maximum likelihood method of WOMBAT. For correlations bivariate animal model was used. Best model was chosen based on likelihood ratio test. The genetic trends were estimated by the weighted regression of the average breeding value of the animals on the year of birth/lambing. Results: The overall least squares mean±standard error of AFL, LI, LS, and ARR were 375±12.5, 284±9.9, 1.45±0.010, and 2.31±0.050, respectively. Direct heritability estimates for AFL, LI, LS, and ARR were 0.07±0.190, 0.06±0.120, 0.18±0.070, and 0.25±0.203, respectively. The low heritability for both AFL and LI showed that these traits respond little to selection programs but rather highly depend on animal management options. The annual genetic gains were -0.0281 days, -0.016 days, -0.0002 lambs and 0.0003 lambs for AFL, LI, LS, and ARR, respectively. Conclusion: Implications of the result to future improvement programs were improving management of animals, conservation of prolific flocks and out scaling the CBBP to get better results.

• Korean Journal of Veterinary Research
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• v.30 no.4
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• pp.499-505
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• 1990

The seasonal availability and abundance of the free-living stages of sheep nematodes is a key factor in the occurrence and severity of parasitic infection, and studies of larvae ecology could result in more rational control measures. In the present study seasonal pasture contamination and availability of nematodes for grazing sheep was examined as a baseline work for nematode control program at Namwon Branch, National Animal Breeding Institute during the period April 1988 through March 1989. Standard meteorological measurements were available from Unbong Sub-station, Honam Crops Experiment Station located about 200m from the experimental site. A total of 5 kinds of nematode larvae was detected: Haemonchus contortus was most prevalent (38.0%) with a decreasing order of Ostertagia spp (35.1%), Trichostrongylus spp (19.8%), nematodirus spp (6.6%), and Oesophagostomum spp (0.5%). A succession of species was recorded, in particular Ostertagia spp in May; Haemonchus contortus in June and July; Trichostrongylus spp in July and August; Nematodirus spp in August and September. These results can be incorporated into the nematode control program. To make a more rational control program, however, repeated herbage larval counts should be undertaken soil larval counts and fecal larval counts in the future.

• The Plant Pathology Journal
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• v.30 no.4
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• pp.343-354
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• 2014

Rice blast disease caused by Magnaporthe oryzae is one of the most serious diseases of cultivated rice (Oryza sativa L.) in most rice-growing regions of the world. In order to investigate early response genes in rice, we utilized the transcriptome analysis approach using a 300 K tilling microarray to rice leaves infected with compatible and incompatible M. oryzae strains. Prior to the microarray experiment, total RNA was validated by measuring the differential expression of rice defense-related marker genes (chitinase 2, barwin, PBZ1, and PR-10) by RT-PCR, and phytoalexins (sakuranetin and momilactone A) with HPLC. Microarray analysis revealed that 231 genes were up-regulated (>2 fold change, p < 0.05) in the incompatible interaction compared to the compatible one. Highly expressed genes were functionally characterized into metabolic processes and oxidation-reduction categories. The oxidative stress response was induced in both early and later infection stages. Biotic stress overview from MapMan analysis revealed that the phytohormone ethylene as well as signaling molecules jasmonic acid and salicylic acid is important for defense gene regulation. WRKY and Myb transcription factors were also involved in signal transduction processes. Additionally, receptor-like kinases were more likely associated with the defense response, and their expression patterns were validated by RT-PCR. Our results suggest that candidate genes, including receptor-like protein kinases, may play a key role in disease resistance against M. oryzae attack.

• FLOWER RESEARCH JOURNAL
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• v.19 no.4
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• pp.219-224
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• 2011

Phalaenopsis (P.) has various species, and some of them have strong fragrance. There are fragrant species such as P. bellina, P. violacea, P. schilleriana and used in breeding program for fragrant Phalaenopsis. This study was performed for establishment of fragrance analysis system using GC-MS and electronic nose in eight P. resources. We analyzed fragrant compound using the tissue of sepal, petal, column, and lip of P. '3010'. The percentage of the major compound was high in the petal and lip tissues. The main compound emitted from P. bellina was linalool (21.21%). It was possible that fragrance pattern could be analyzed among the resources using the electronic nose. Discriminant function analysis (DFA) was more useful than the principal component analysis (PCA) in statistics program. We utilized GC-MS method for the major compounds of flower from our breeding materials. This study would be useful to the fragrant analysis system for the fragrant orchid breeding in the future.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.807-812
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• 2013

In this study, we aimed to develop a simple analysis method for measuring the carotenoids content of pepper powder. A 96-wells polystyrene microplate and an ELISA reader were used for analysis. Although ELISA reader with 450 nm filter was applicable to measure carotenoid contents, the surface of microplates were degenerated by acetone used for carotenoids extraction. However, ten-folded dilute of the color extract with methanol did not affect the surface of polystyrene microplate and components of the color extract could be successfully measured by a ELISA reader, showing a high corelation with ASTA-20.1 method. In addition, this method uses 10 fold less acetone than ASTA-20.1 method resulting less acetone waste. The microplate method using ELISA reader has potential power for analyzing a large number of samples which may be very useful to the practical breeding program for high-colored peppers.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.461-466
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• 2011

In genetic and molecular breeding studies of plants, researchers need to design various kinds of primers based on their research purposes. So far many kinds of web- or script-based non-commercial programs for primer design are available. Because most of them do not include user interface for multipurpose usage including gene structure prediction and direct target selection on sequences, it has been a laborious work to design primers targeting on the exon or intron regions of interesting genes. Here we report a primer designing graphic user interface program, Pickprimer, that includes gene structure prediction and primer design modules by combining source codes of the Spidey and Primer3 programs. This program provides simple graphic user interface to input sequences and design primers. Genomic sequence and mRNA or coding sequence of genes can be copy and pasted or input as fasta or text files. Based on alignment of the input sequences using the Spidey module, a putative gene structure is graphically visualized along with exon-intron sequences of color codes. Primer design can be easily performed by dragging mouse on the displayed sequences or input primer targeting position with desirable values of primers. The output of designed primers with detailed information is provided by the Primer3 module. PCR evaluation of 24 selected primer sets successfully amplified single amplicons from six Brassica rapa cultivars. The Pickprimer will be a convenient tool for genetic and molecular breeding studies of plants.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2029-2035
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• 2018

Cycloisomaltooligosaccharide glucanotransferase (CITase) was isolated from alkaliphilic Paenibacillus daejeonensis via an amino acid homology search for the reported CITase. The recombinant alkaliphilic CITase (PDCITase) from P. daejeonensis was expressed in an Escherichia coli expression system and purified as a single protein band of 111 kDa. PDCITase showed optimum activity at pH 8.0 and retained 100% of activity within a broad pH range (7.0-11.5) after 18 h, indicating alkaliphilic or alkalistable CITase properties. In addition, PDCITase produced CI-7 to CI-17, CI-18, and CI-19, which are relatively large cycloisomaltooligosaccharides yet to be reported. Therefore, these large cycloisomaltooligosaccharides can be applied to the improvement of water solubility of pharmaceutical biomaterials.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.261-271
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• 2016

Citrus is an economically important fruit crop widely growing worldwide. However, citrus production largely depends on natural hybrid selection and bud sport mutation. Unique botanical features including long juvenility, polyembryony, and QTL that controls major agronomic traits can hinder the development of superior variety by conventional breeding. Diverse factors including drastic changes of citrus production environment due to global warming and changes in market trends require systematic molecular breeding program for early selection of elite candidates with target traits, sustainable production of high quality fruits, cultivar diversification, and cost-effective breeding. Since the construction of the first genetic linkage map using isozymes, citrus scientists have constructed linkage maps using various DNA-based markers and developed molecular markers related to biotic and abiotic stresses, polyembryony, fruit coloration, seedlessness, male sterility, acidless, morphology, fruit quality, seed number, yield, early fruit setting traits, and QTL mapping on genetic maps. Genes closely related to CTV resistance and flesh color have been cloned. SSR markers for identifying zygotic and nucellar individuals will contribute to cost-effective breeding. The two high quality citrus reference genomes recently released are being efficiently used for genomics-based molecular breeding such as construction of reference linkage/physical maps and comparative genome mapping. In the near future, the development of DNA molecular markers tightly linked to various agronomic traits and the cloning of useful and/or variant genes will be accelerated through comparative genome analysis using citrus core collection and genome-wide approaches such as genotyping-by-sequencing and genome wide association study.

• Proceedings of the Korean Society of Crop Science Conference
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• 2021.10a
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• pp.183-183
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• 2021

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.272-280
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• 2016

Chrysanthemum is one of the top floriculture species with ornamental and medicinal value. Although chrysanthemum breeding program has contributed to the development of various cultivars so far, it needs to be advanced from the traditional phenotype-based selection to marker-assisted selection (molecular breeding) as shown in major cereal and vegetable crops. Molecular breeding relies on trait-linked molecular markers identified from genetic, molecular, and genomic studies. However, these studies in chrysanthemum are significantly hampered by the reproductive, genetic, and genomic properties of chrysanthemum such as self-incompatibility, inbreeding depression, allohexaploid, heterozygosity, and gigantic genome size. Nevertheless, several genetic studies have constructed genetic linkage maps and identified molecular markers linked to important traits of flower, leaf, and plant architecture. With progress in sequencing technology, chrysanthemum transcriptome has been sequenced to construct reference gene set and identify genes responsible for developments or induced by biotic or abiotic stresses. Recently, a genome sequencing project has been launched on a diploid wild Chrysanthemum species. The massive sequencing information would serve as fundamental resources for molecular breeding of chrysanthemum. In this review, we summarized the current status of molecular genetics and genomics in chrysanthemum and briefly discussed future prospects.