• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.14-14
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• 2017

The discipline of plant breeding is experiencing a renaissance impacting crop improvement as a result of new technologies, however fundamental questions remain for predicting the phenotype and how the environment and genetics shape it. Inexpensive DNA sequencing, genotyping, new statistical methods, high throughput phenotyping and gene-editing are revolutionizing breeding methods and strategies for improving both quantitative and qualitative traits. Genomic selection (GS) models use genome-wide markers to predict performance for both phenotyped and non-phenotyped individuals. Aerial and ground imaging systems generate data on correlated traits such as canopy temperature and normalized difference vegetative index that can be combined with genotypes in multivariate models to further increase prediction accuracy and reduce the cost of advanced trials with limited replication in time and space. Design of a GS training population is crucial to the accuracy of prediction models and can be affected by many factors including population structure and composition. Prediction models can incorporate performance over multiple environments and assess GxE effects to identify a highly predictive subset of environments. We have developed a methodology for analyzing unbalanced datasets using genome-wide marker effects to group environments and identify outlier environments. Environmental covariates can be identified using a crop model and used in a GS model to predict GxE in unobserved environments and to predict performance in climate change scenarios. These new tools and knowledge challenge the plant breeder to ask the right questions and choose the tools that are appropriate for their crop and target traits. Contemporary plant breeding requires teams of people with expertise in genetics, phenotyping and statistics to improve efficiency and increase prediction accuracy in terms of genotypes, experimental design and environment sampling.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.1
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• pp.56-64
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• 2003

If a quantitative trait loci (QTL) marker identified in a population is applicable to different populations (marker universality), this will not only reduce the labor and cost in marker assisted selection (MAS), but accelerate the application of molecular markers to real breeding programs. Present study aims to evaluate the defined QTL related markers from a population to a different breeding population for the MAS. Four rice breeding populations were subjected to seventy-five simple sequence repeat (SSR) markers which were already identified for their polymorphism information content (PIC) in the parents of the crossings. Among them, eight markers were evaluated for their correlation between presence of marker alleles and phenotypic expression in breeding populations. A reasonable level of polymorphism for the mapped markers originated from any sources of rice accessions was observed between crosses of any sources (marker repeatability). However, correlation between presence of markers and expression of the traits in rice breeding populations was not significant except for minor portion of traits and markers examined (failure of marker universality). In the present study, various strategies were discussed to develop new markers with universality of breeding application.

• Journal of Ginseng Research
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• v.14 no.1
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• pp.50-56
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• 1990

Root-rot of ginseng caused by Fusarium solani is one of the most obstacles to ginseng cultivation. We evaluated some inoculating techniques of ginseng with Fusarium solani, for selection of disease resistant breeding lines. The most effective inoculating techniques evaluated were inserting toothpicks colonized by F. solani into the seedling roots in laboratory test and dusting seedlings with vermiculite after dipping in conidial sllspension and then replanting method in field test. The resistance to diseased by F. solani was lines of 82022 and 82066 in laboratory test. 82920-1 and 78093 in field test.

• Journal of Applied Biological Chemistry
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• v.43 no.4
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• pp.197-206
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• 2000

This paper summarizes recent developments in the field of molecular biology and its application to plant breeding, particularly in rice. Plant breeding in the past mostly depended on the time-consuming crossing of known genomes limited to certain traits. Plant breeding has now benefited from marker-assisted selection and genetic engineering to widen the gene pool, improve plant protection, and increase yield. Future plant breeding will expand based on functional and nutritional genomics, in which gene discovery and high-throughput transformation will accelerate crop design and benefits will accrue to human health, in the form of nutritional food for poor people to reduce malnutrition, or food enriched with antioxidants and with high food value for rich people. Agricultural biotechnology for food is no longer a dream but a reality that will dominate the 21st century for agriculture and human welfare.

• Animal Bioscience
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• v.35 no.11
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• pp.1635-1648
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• 2022

Thermal stress due to extreme changes in the thermal environment is a critical issue in cattle production. Many previous findings have shown a decrease in feed intake, milk yield, growth rate, and reproductive efficiency of cattle when subjected to thermal stress. Therefore, selecting thermo-tolerant animals is the primary goal of the efficiency of breeding programs to reduce those adverse impacts. The recent advances in molecular genetics have provided significant breeding advantages that allow the identification of molecular markers in both beef and dairy cattle breeding, including marker-assisted selection (MAS) as a tool in selecting superior thermo-tolerant animals. Single-nucleotide polymorphisms (SNPs), which can be detected by DNA sequencing, are desirable DNA markers for MAS due to their abundance in the genome's coding and non-coding regions. Many SNPs in some genes (e.g., HSP70, HSP90, HSF1, EIF2AK4, HSBP1, HSPB8, HSPB7, MYO1A, and ATP1A1) in various breeds of cattle have been analyzed to play key roles in many cellular activities during thermal stress and protecting cells against stress, making them potential candidate genes for molecular markers of thermotolerance. This review highlights the associations of SNPs within these genes with thermotolerance traits (e.g., blood biochemistry and physiological responses) and suggests their potential use as MAS in thermotolerant cattle breeding.

• Journal of Crop Science and Biotechnology
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• v.10 no.4
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• pp.211-222
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• 2007

Selection of the appropriate parents to be used in artificial crosses is one of the main decisions faced by plant breeders that will facilitate the exploitation of maximum genetic variability and production of superior recombinant genotypes. Several techniques have been used in aiding the identification of genotypes with promising and desirable agronomical traits for hybridization. In this way, the objective of the present review is to gather available information for the selection of parents based on different breeding designs and analytical tools showing their similarities and highlighting the main advantages and disadvantages of their use.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.747-755
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• 2009

The feed resource for animals is a major cost determinant for profitability in livestock production enterprises, and thus any effort at improving the efficiency of feed use will help to reduce feed cost. Feed conversion ratio, expressed as feed inputs per unit output, is a traditional measure of efficiency that has significant phenotypic and genetic correlations with feed intake and growth traits. The use of ratio traits for genetic selection may cause problems associated with prediction of change in the component traits in future generations. Residual feed intake, a linear index, is a trait derived from the difference between actual feed intake and that predicted on the basis of the requirements for maintenance of body weight and production. Considerable genetic variation exists in residual feed intake for cattle and pigs, which should respond to selection. Phenotypic independence of phenotypic residual feed intake with body weight and weight gain can be obligatory. Genetic residual feed intake is genetically independent of its component traits (body weight and weight gain). Genetic correlations of residual feed intake with daily feed intake and feed conversion efficiency have been strong and positive in both cattle and pigs. Residual feed intake is favorably genetically correlated with eye muscle area and carcass weight in cattle and with eye muscle area and backfat in pigs. Selection to reduce residual feed intake (excessive intake of feed) will improve the efficiency of feed and most of the economically important carcass traits in cattle and pigs. Therefore, residual feed intake can be used to replace traditional feed conversion ratio as a selection criterion of feed efficiency in breeding programs. However, further studies are required on the variation of residual feed intake during different developmental stage of production.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.2
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• pp.117-120
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• 1998

Relationships of breeding values of sires for first lactation milk yield with pedigree information or indices were examined to identify the optimal criteria of selecting young dairy bulls for future use in artificial insemination (AI). Records of performance data on 1087 crossbred daughters (Holstein - Friesian, Jersey and Brown Swiss with Hariana) of 147 sires, generated at Livestock Production Research (Cattle and Buffaloes) Farm, IVRI, Izatnagar, U.P., during 1972 - 1995 were used to obtain the estimates of sire's breeding values (EBV) using the Best Linear Unbiased Prediction Procedures. The correlations between young bull's EBV and the dam's first lactation milk yield was non-significantly different from zero. However, the young bull's EBV was negatively and significantly related (r = - 0.275 ; P < 0.05) to the dam's best lactation milk yield, suggesting that the selection of young dairy bulls from high yielding elite dams is not a suitable criteria for genetic improvement. The correlations of sire's and paternal grandsire's EBV's with young bull's EBV were high and positive (0.532, 0.844; P < 0.01). The maternal grandsire's EBV was positively but non-significantly related to grandson's EBV. The pedigree index incorporating dam's milk records and sire's EBV's showed a negative and non-significant correlation with young bull's EBV. However, the correlation of a pedigree index $(I_3)$ combining information on sire's and paternal grand-sire's EBV's with young bull's EBV's was considerably high and positive (0.797; P < 0.01). The regression coefficients of young bull's EBV on pedigree index $I_3$, was higher than those on other pedigree information. These results revealed that there was no advantage in basing selection on dam's performance or maternal grand-sire's EBV and that sire's and paternal grandsire's EBV's were reliable pedigree information for selection of young dairy bulls for future use in AI.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.5
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• pp.712-721
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• 2020

Objective: The Wannan Black pig is a typical Chinese indigenous, disease-resistant pig breed with high fertility, and a crude-feed tolerance that has been bred by artificial selection in the south of Anhui province for a long time. However, genome variation, genetic relationships with other pig breeds, and domestication, remain poorly understood. Here, we focus on elucidating the genetic characteristics of the Wannan Black pig and identifying selection signatures during domestication and breeding. Methods: We identified the whole-genome variation in the Wannan Black pig and performed population admixture analyses to determine genetic relationships with other domesticated pig breeds and wild boars. Then, we identified the selection signatures between the Wannan Black pig and Asian wild boars in 100-kb windows sliding in 10 kb steps by using two approaches: the fixation index (F_ST) and π ratios. Results: Resequencing the Wannan Black pig genome yielded 501.52 G of raw data. After calling single-nucleotide variants (SNVs) and insertions/deletions (InDels), we identified 21,316,754 SNVs and 5,067,206 InDels (2,898,582 inserts and 2,168,624 deletions). Additionally, we found genes associated with growth, immunity, and digestive functions. Conclusion: Our findings help in explaining the unique genetic and phenotypic characteristics of Wannan Black pigs, which in turn can be informative for future breeding programs of Wannan Black pigs.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.11
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• pp.1483-1503
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• 2011

To advance the effectiveness of the current Hanwoo improvement system, we developed a general simulation that compared a series of breeding schemes under realistic user circumstances. We call this system the Integrated General Model (IGM) and it allows users to control the breeding schemes and selection methods by manipulating the input parameters. The Current Hanwoo Performance and Progeny Test (CHPPT) scheme was simulated with a Modified Hanwoo Performance and Progeny Test (MHPPT) scheme using a Hanwoo Breeding Farm cow population of the Livestock Improvement Main Center (LOMC) of the National Agricultural Cooperatives Federation (NACF). To compare the two schemes, a new method, the Simple Hanwoo Performance Test (SHPT), which uses ultrasound technology for measuring the carcass traits of live animals, was developed. These three models, including the CHPPT, incorporated three types of selection criteria: phenotype (PH), true breeding value (TBV), and estimated breeding value (EBV). The simulation was scheduled to mimic an actual Hanwoo breeding program; thus, the simulation was run to include the years 1983-2020 for each breeding method and was replicated 10 times. The parameters for simulation were derived from the literature. Approximately 642,000 animals were simulated per replication for the CHPPT scheme; 129,000 animals were simulated for the MHPPT scheme and 112,000 animals for the SHPT scheme. Throughout the 38-year simulation, all estimated parameters of each simulated population, regardless of population size, showed results similar to the input parameters. The deviations between input and output values for the parameters in the large populations were statistically acceptable. In this study, we integrated three simulated models, including the CHPPT, in an attempt to achieve the greatest genetic gains within major economic traits including body weight at 12 months of age (BW12), body weight at 24 months of age (BW24), average daily gain from 6 to 12 months (ADG), carcass weight (CWT), carcass longissimus muscle area (CLMA), carcass marbling score (CMS), ultrasound scanned longissimus muscle area (ULMA), and ultrasound scanned marbling score (UMS).