• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.634-639
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• 1998

A methodology based on the concept of variable string length GA(VGA) is developed for determining automatically the number of hyperplanes and their appropriate arrangement for modeling the class boundaries of a given training data set in RN. The genetic operators and fitness functionare newly defined to take care of the variability in chromosome length. Experimental results on different artificial and real life data sets are provided.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.1
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• pp.69-73
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• 2003

Specific leaf weight (SLW), defined as the mass of tissue per unit leaf area has been found to be an important physiological parameter as it indicates the relative thickness of leaves. Greater SLW provides more photosynthetic potential per unit area of leaf and hence it is frequently been considered as correlated with photosynthesis in several plant species. Collections of 165 mulberry (Morus sp.) germplasm accessions, both Indian and exotic in origin were evaluated for their variability with respect to SLW. The mean specific leaf weight ranged from 35.3 to $72.3 g/m^{-2}$. The distribution of SLW was found to be normal. High heritability (97.08%) and a small difference between genotypic and phenotypic variance demonstrates the genetic control over SLW. Significant heterotic effect with respect to SLW was observed in crosses when parents with high and low SLW were chosen.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1536-1542
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• 2002

The genetic variability of three poultry breeds namely Aseel, Miri and Nicobari taken from different geographical locations of India were evaluated using 15 microsatellite loci. No. of alleles varied from 3 to 9 in Aseel, 3 to 8 in Miri and 2 to 7 in Nicobari. Mean PIC values in Aseel, Miri and Nicobari breeds were 0.64, 0.66 and 0.63, respectively. Average unbiased heterozygosity and direct count heterozygosity were 0.65 and 0.59, 0.68 and 0.61, and 0.64 and 0.57 in Aseel, Miri and Nicobari breeds, respectively. High heterozygosity values revealed in this study are indicative of low level of inbreeding, large population size and no or low selection pressure for commercial trait in all three populations. The estimate of genetic distances using Nei's standard, Nei's minimum and Reynold's distance revealed Aseel and Nicobari to be more closely related than Miri breed of poultry.

• Journal of Life Science
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• v.10 no.1
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• pp.14-19
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• 2000

Variation at 25 allozyme loci in Korean wateralder (Alnus hirsuta Rupr.) from nine distinct populations was measured to estimate the amount and pattern of genetic diversity and population structure. The mean genetic diversity within population was 0.166. Korean alder populations have slightly high levels of genetic diversity compared to those present in associated temperature-zone species and two Canadian alder species. Among population s genetic differentiation accounted for an significant 9% of the total variation. High gene flow(Nm=2.63) was observed. Analysis of fixation indices, calculated for all polymorphic loci in each population, showed a substantial deficiency of heterozygotes relative to Hardy-Weinberg expectations. The mean GST value A. hirsuta in Korea (GST = 0.087) is similar to those of A. rogosa in Canada (GST = 0.052). These low values of GST in two countries. reflecting little spatial genetic differentiation, may indicate extensive gene flow (via pollen and/or seeds) and/or recent colonization. These factors reduce the effect of geographic isolation of breeding and the chance for genetic divergence. A pattern of increasing is observed with increasing rainfall per year. Regression analysis indicates that 54% (F = 4.67) of the variability observed can be explained by this relationship.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.1
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• pp.14-19
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• 2015

The genetic diversity of native chicken populations from Myanmar, Thailand, and Laos was examined by using 102 insertion and/or deletion (indels) markers. Most of the indels loci were polymorphic (71% to 96%), and the genetic variability was similar in all populations. The average observed heterozygosities ($H_O$) and expected heterozygosities ($H_E$) ranged from 0.205 to 0.263 and 0.239 to 0.381, respectively. The coefficients of genetic differentiation (Gst) for all cumulated populations was 0.125, and the Thai native chickens showed higher Gst (0.088) than Myanmar (0.041) and Laotian (0.024) populations. The pairwise Fst distances ranged from 0.144 to 0.308 among populations. A neighbor-joining (NJ) tree, using Nei's genetic distance, revealed that Thai and Laotian native chicken populations were genetically close, while Myanmar native chickens were distant from the others. The native chickens from these three countries were thought to be descended from three different origins (K = 3) from STRUCTURE analysis. Genetic admixture was observed in Thai and Laotian native chickens, while admixture was absent in Myanmar native chickens.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.12
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• pp.1685-1690
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• 2006

Kenkatha cattle, a draft purpose breed, which can survive in a harsh environment on low quality forage, was explored genetically exploiting FAO-suggested microsatellite markers. The microsatellite genotypes were derived by means of the polymerase chain reaction (PCR) followed by electrophoretic separation in agarose gels. The PCR amplicons were visualized by silver staining. The allelic as well as genotypic frequencies, heterozygosities and gene diversity were estimated using standard techniques. A total of 125 alleles was distinguished by the 21 microsatellite markers investigated. All the microsatellites were highly polymorphic with mean allelic number of 5.95${\pm}$1.9 (ranging from 3-10 per locus). The observed heterozygosity in the population ranged between 0.250 and 0.826 with a mean of 0.540${\pm}$0.171, signifying considerable genetic variation. Bottleneck was examined assuming all three mutation models which showed that the population has not experienced bottleneck in recent past. The population displayed a heterozygote deficit of 21.4%. The study suggests that the breed needs to be conserved by providing purebred animals in the breeding tract.

• Parasites, Hosts and Diseases
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• v.52 no.5
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• pp.557-564
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• 2014

The vir genes are antigenic genes and are considered to be possible vaccine targets. Since India is highly endemic to Plasmodium vivax, we sequenced 5 different vir genes and investigated DNA sequence variations in 93 single-clonal P. vivax isolates. High variability was observed in all the 5 vir genes; the vir 1/9 gene was highly diverged across Indian populations. The patterns of genetic diversity do not follow geographical locations, as geographically distant populations were found to be genetically similar. The results in general present complex genetic diversity patterns in India, requiring further in-depth population genetic and functional studies.

• The Korean Journal of Malacology
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• v.18 no.1
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• pp.9-14
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• 2002

In order to estimate the genetic variability and differentiation in common squid, eleven isozymic loci, coded for nine enzymes detected by starch gel electrophoresis, were scored from nine spawning cohorts in four localities. The expected average heterozygosity ranged from 0.00019 (between II-S$_2$ and Na-W) to 0.00814 (Between Bu-S and Na-W) in nine different spawning cohorts in four localities. A dendrogram, based on genetic distance mentioned, illustrated that nine different spawning cohorts were divided into three groups, similar to the result estimated by their ecological characterizations. From these results, we estimate that the common squid distributed throughout Korean waters will maintain this gene exchange. It is postulated that either the summer or the autumn spawning cohort has developed a local population that is isolated by hydrographic factors.

• The Korean Journal of Mycology
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• v.25 no.2 s.81
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• pp.111-120
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• 1997

The characteristics of monosporous isolates of winter mushroom [Flammulina velutipes (Curt. ex Fr.)] were investigated to obtain useful breeding materials. Within monokaryons from cultivars which have a white colored fruitbody showed narrow genetic variation, while domestic strains which have a brown colored fruitbody showed wide variation. The mating type of the white strains was A1A2B1B2 genotype, but that of the domestic brown strains were A3A4B3B4. In intra-crossing, the genetic stability of dikaryons mated by monokaryons from white strain was less than that of parents. While in brown strain, dikaryons with high yield and color variation were obtained.

• The Plant Pathology Journal
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• v.31 no.3
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• pp.203-211
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• 2015

Maize is the dominant cereal crop produced in the US. One of the main fungal pathogens of maize is Fusarium verticillioides, the causative agent of ear and stalk rots. Significantly, the fungus produces a group of mycotoxins - fumonisins - on infested kernels, which have been linked to various illnesses in humans and animals. Nonetheless, durable resistance against F. verticillioides in maize is not currently available. In Texas, over 2.1 million acres of maize are vulnerable to fumonisin contamination, but understanding of the distribution of toxigenic F. verticillioides in maize-producing areas is currently lacking. Our goal was to investigate the genetic variability of F. verticillioides in Texas with an emphasis on fumonisin trait and geographical distribution. A total of 164 F. verticillioides cultures were isolated from 65 maize-producing counties. DNA from each isolate was extracted and analyzed by PCR for the presence of FUM1- a key fumonisin biosynthesis gene - and mating type genes. Results showed that all isolates are in fact F. verticillioides capable of producing fumonisins with a 1:1 mating-type gene ratio in the population. To further study the genetic diversity of the population, isolates were analyzed using RAPD fingerprinting. Polymorphic markers were identified and the analysis showed no clear correlation between the RAPD profile of the isolates and their corresponding geographical origin. Our data suggest the toxigenic F. verticillioides population in Texas is widely distributed wherever maize is grown. We also hypothesize that the population is fluid, with active movement and genetic recombination occurring in the field.