QTLs Mapping for Salinity Tolerance at Seedling Stage or Rice(Oryza sativa L.) Using Chromosome Segment Substitution Lines

In this study, a population of chromosome segment substitution lines （CSSLs） derived from the cross between 9311 （indica） and Nipponbare （japonica） was employed to map the quantitative trait loci （QTLs） for salt tolerance under the salt stress simulated with 0.5% NaCI, using survival rate as the index. The data were analyzed by QTL IciMapping v3.1, and the results showed that one QTL （QSsr3） related to salt tolerance was located in the vicinity of the marker RM1350 on chromosome 3, into a genetic interval of 113.2-132.8 cM, with a contribution rate of 17.75%. The additive effect was 10.9, indicating that the QTL derived from the parent Nipponbare improved the salt tolerance of rice at seedling stage. This study will provide a theoretical basis for the selection of salt tolerant rice germplasm.

Mapping QTLs Associated with Sheath Blight Resistance Using Chromosome Segment Substitution Lines of Rice(Oryza sativa L.)

In this study, a population of 119 chromosome segment substitution lines （CSSLs） derived from backcross between indica 9311 and japonica Nipponbare was employed to map quantitative trait loci （QTL） associated with sheath blight resis-tance in rice with toothpick inoculation method. A total of three sheath blight resis-tance-associated QTLs （qsb8-1, qsb8-2 and qsb8-3） were identified, which were lo-cated on adjacent molecular markers RM3262, RM5485 and RM3496 of chromo-some 8; the genetic interval was 81.7cM-91.7cM, 91.7cM-108.1cM and 108.1cM-119.6cM, respectively. The additive effect of qsb8-2 was negative, indicating that sheath blight resistance of susceptible parent harboring qsb8-2 fragment was en-hanced; additive effects of qsb8-1 and qsb8-3 were positive, indicating that sheath blight resistance of susceptible parent harboring qsb8-1 and qsb8-3 fragments was reduced.

Identifying genetic susceptibility to Aspergillus fumigatus infection using collaborative cross mice and RNA-Seq approach

Background:Aspergillus fumigatus(Af)is one of the most ubiquitous fungi and its infection potency is suggested to be strongly controlled by the host genetic back-ground.The aim of this study was to search for candidate genes associated with host susceptibility to Aspergillus fumigatus(Af)using an RNAseq approach in CC lines and hepatic gene expression.Methods:We studied 31 male mice from 25 CC lines at 8 weeks old;the mice were infected with Af.Liver tissues were extracted from these mice 5 days post-infection,and next-generation RNA-sequencing(RNAseq)was performed.The GENE-E analysis platform was used to generate a clustered heat map matrix.Results:Significant variation in body weight changes between CC lines was ob-served.Hepatic gene expression revealed 12 top prioritized candidate genes differ-entially expressed in resistant versus susceptible mice based on body weight changes.Interestingly,three candidate genes are located within genomic intervals of the previ-ously mapped quantitative trait loci(QTL),including Gm16270 and Stox1 on chromo-some 10 and Gm11033 on chromosome 8.Conclusions:Our findings emphasize the CC mouse model's power in fine mapping the genetic components underlying susceptibility towards Af.As a next step,eQTL analysis will be performed for our RNA-Seq data.Suggested candidate genes from our study will be further assessed with a human cohort with aspergillosis.

Weighted total variation using split Bregman fast quantitative susceptibility mapping reconstruction method

An ill-posed inverse problem in quantitative susceptibility mapping （QSM） is usually solved using a regularization and optimization solver, which is time consuming considering the three-dimensional volume data. However, in clinical diagnosis, it is necessary to reconstruct a susceptibility map efficiently with an appropriate method. Here, a modified QSM reconstruction method called weighted total variation using split Bregman （WTVSB） is proposed. It reconstructs the susceptibility map with fast computational speed and effective artifact suppression by incorporating noise-suppressed data weighting with split Bregman iteration. The noise-suppressed data weighting is determined using the Laplacian of the calculated local field, which can prevent the noise and errors in field maps from spreading into the susceptibility inversion. The split Bregman iteration accelerates the solution of the Ll-regularized reconstruction model by utilizing a preconditioned conjugate gradient solver. In an experiment, the proposed reconstruction method is compared with truncated k-space division （TKD）, morphology enabled dipole inversion （MEDI）, total variation using the split Bregman （TVSB） method for numerical simulation, phantom and in vivo human brain data evaluated by root mean square error and mean structure similarity. Experimental results demonstrate that our proposed method can achieve better balance between accuracy and efficiency of QSM reconstruction than conventional methods, and thus facilitating clinical applications of QSM.

Detecting mislabeling and identifying unique progeny in Acacia mapping population using SNP markers

Acacia hybrids offer a great potential for paper industry in Southeast Asia due to their fast growth and ability to grow on abandoned or marginal lands. Breeding Acacia hybrids with desirable traits can be achieved through marker assisted selection(MAS) breeding. To develop a MAS program requires development of linkage maps and QTL analysis. Two mapping populations were developed through interspecific hybridization for linkage mapping and QTL analysis. All seeds per pod were cultured initially to improve hybrid yield as quality and density of linkage mapping is affected by the size of the mapping population. Progenies from two mapping populations were field planted for phenotypic and genotypic evaluation at three locations in Malaysia,(1) Forest Research Institute Malaysia field station at Segamat, Johor,(2) Borneo Tree Seeds and Seedlings Supplies Sdn, Bhd.(BTS) field trial site at Bintulu, Sarawak, and(3) Asiaprima RCF field trial site at Lancang, Pahang. During field planting, mislabeling was reported at Segamat, Johor, and a similar problem was suspected for Bintulu, Sarawak. Early screening with two isozymes effectively selected hybrid progenies, and these hybrids were subsequently further confirmed by using species-specific SNPs. During field planting, clonal mislabeling was reported and later confirmed by using a small set of STMS markers. A large set of SNPs were also used to screen all ramets in both populations. A total of 65.36% mislabeled ramets were encountered in the wood density population and 60.34% in the fibre length mapping population. No interpopulation pollen contamination was detected because all ramets found their match within the same population in question.However, mislabeling was detected among ramets of the same population. Mislabeled individuals were identified and grouped as they originated from 93 pods for wood density and 53 pods for fibre length mapping populations.On average 2 meiotically unique seeds per pod(179 seeds/93 pods) for wood density and 3 meiotically unique seeds per pod(174 seeds/53 pods) for fibre length mapping population were found. A single step statistical method was used to evaluate the most informative set of SNPs that could subsequently be used for routine checks for mislabeling in multi-location field trials and for labelling superior clones to protect breeder’s rights. A preliminary set of SNPs with a high degree of informativeness was selected for the mislabeling analysis in conjunction with an assignment test. Two subsets were successfully identified,i.e., 51 SNPs for wood density and 64 SNPs for fibre length mapping populations to identify all mislabeled ramets which had been previously identified. Mislabeling seems to be a common problem due to the complexity involved in the production of mapping populations. Therefore, checking for mislabeling is imperative for breeding activities and for analyses such as linkage mapping in which a correlation between genotypic and phenotypic data is determined.

Rice molecular markers and genetic mapping:Current status and prospects

Dramatic changes in climatic conditions that supplement the biotic and abiotic stresses pose severe threat to the sustainable rice production and have made it a difficult task for rice molecular breeders to enhance production and productivity under these stress factors. The main focus of rice molecular breeders is to understand the fundamentals of molecular pathways involved in complex agronomic traits to increase the yield. The availability of complete rice genome sequence and recent improvements in rice genomics research has made it possible to detect and map accurately a large number of genes by using linkage to DNA markers. Linkage mapping is an effective approach to identify the genetic markers which are co-segregating with target traits within the family. The ideas of genetic diversity, quantitative trait locus（QTL） mapping, and marker-assisted selection（MAS） are evolving into more efficient concepts of linkage disequilibrium（LD） also called association mapping and genomic selection（GS）, respectively. The use of cost-effective DNA markers derived from the fine mapped position of the genes for important agronomic traits will provide opportunities for breeders to develop high-yielding, stress-resistant, and better quality rice cultivars. Here we focus on the progress of molecular marker technologies, their application in genetic mapping and evolution of association mapping techniques in rice.

MRI Evaluation of Lateral Geniculate Body in Normal Aging Brain Using Quantitative Susceptibility Mapping

Objective To investigate the changes of lateral geniculate body （LGB） in the normal aging brain using quantitative susceptibility mapping （QSM） technique. Methods Magnetic resonance （MR） phase and magnitude images were acquired from enhanced gradient echo T2 star weighted angiography sequence with 16 echoes on 3.0T MR system using the head coil with 32 channels. Morphology Enabled Dipole Inversion （MEDI） method was applied for QSM, and the susceptibility value of LGB was measured by region of interest （ROI） drawn manually on three orthogonal planes. Results LGB of the middle-aged group had a higher susceptibility value （0.16±0.05 ppm） than that of the youth group （0.12±0.05 pprn） and elderly group （0.13±0.03 ppm） （all P〈0.05）. Partial correlation analysis demonstrated that there was significantly positive correlation between susceptibility value and age in the youth group （r=0.71, P〈0.05）. Conclusion LGB could clearly be identified on QSM in the brain in vivo.

Unraveling waterlogging tolerance-related traits with QTL analysis in reciprocal intervarietal introgression lines using genotyping by sequencing in rapeseed(Brassica napus L.)

Soil waterlogging is a major environmental stress that suppresses the growth and productivity of rapeseed(Brassica napus L.).Natural genetic variations in waterlogging tolerance(WT)were observed but no QTL mapping has been done for WT related traits in rapeseed.In this study,QTL associated with three WT related traits including relative root length(RRL),relative hypocotyl length(RHL)and relative fresh weight(RFW)were dissected using a set of reciprocal introgression lines(ILs)derived from the cross GH01×ZS9,which showed significant difference in WT.Genotyping-by-sequencing(GBS)of the populations were performed,totally 1468 and 1450 binned SNPs were identified for GIL(GH01 as the recurrent parent)and ZIL(ZS9 as the recurrent parent)population,respectively.A total of 66 distinct QTLs for WT at the seedling establishment stage including 31 for RRL,17 for RHL and 18 for RFW were detected.Among the 66 QTLs,20(29.4%)QTLs were detected in both genetic backgrounds and then they were integrated into six QTL clusters,which can be targeted in rapeseed breeding for improvement of WT through marker-assisted selection(MAS).Based on the physical positions of SNPs and the functional annotation of the Arabidopsis thaliana genome,56 genes within the six QTL cluster regions were selected as preliminary candidate genes,then the resequencing and transcriptome information about parents were applied to narrow the extent of candidate genes.Twelve genes were determined as candidates for the six QTL clusters,some of them involved in RNA/protein degradation,most of them involved in oxidation-reduction process.These findings provided genetic resources,candidate genes to address the urgent demand of improving WT in rapeseed breeding.

A multiple-tissue-specific magnetic resonance imaging model for diagnosing Parkinson’s disease: a brain radiomics study

Brain radiomics can reflect the characteristics of brain pathophysiology.However,the value of T1-weighted images,quantitative susceptibility mapping,and R2*mapping in the diagnosis of Parkinson’s disease(PD)was underestimated in previous studies.In this prospective study to establish a model for PD diagnosis based on brain imaging information,we collected high-resolution T1-weighted images,R2*mapping,and quantitative susceptibility imaging data from 171 patients with PD and 179 healthy controls recruited from August 2014 to August 2019.According to the inclusion time,123 PD patients and 121 healthy controls were assigned to train the diagnostic model,while the remaining 106 subjects were assigned to the external validation dataset.We extracted 1408 radiomics features,and then used data-driven feature selection to identify informative features that were significant for discriminating patients with PD from normal controls on the training dataset.The informative features so identified were then used to construct a diagnostic model for PD.The constructed model contained 36 informative radiomics features,mainly representing abnormal subcortical iron distribution(especially in the substantia nigra),structural disorganization(e.g.,in the inferior temporal,paracentral,precuneus,insula,and precentral gyri),and texture misalignment in the subcortical nuclei(e.g.,caudate,globus pallidus,and thalamus).The predictive accuracy of the established model was 81.1±8.0%in the training dataset.On the external validation dataset,the established model showed predictive accuracy of 78.5±2.1%.In the tests of identifying early and drug-naïve PD patients from healthy controls,the accuracies of the model constructed on the same 36 informative features were 80.3±7.1%and 79.1±6.5%,respectively,while the accuracies were 80.4±6.3%and 82.9±5.8%for diagnosing middle-to-late PD and those receiving drug management,respectively.The accuracies for predicting tremor-dominant and non-tremor-dominant PD were 79.8±6.9%and 79.1±6.5%,respectively.In conclusion,the multiple-tissue-specific brain radiomics model constructed from magnetic resonance imaging has the ability to discriminate PD and exhibits the advantages for improving PD diagnosis.

The neuroimaging of neurodegenerative and vascular disease in the secondary prevention of cognitive decline

Structural brain changes indicative of dementia occur up to 20 years before the onset of clinical symptoms. Efforts to modify the disease process after the onset of cognitive symptoms have been unsuccessful in recent years. Thus, future trials must begin during the preclinical phases of the disease before symptom onset. Age related cognitive decline is often the result of two coexisting brain pathologies: Alzheimer's disease(amyloid, tau, and neurodegeneration) and vascular disease. This review article highlights some of the common neuroimaging techniques used to visualize the accumulation of neurodegenerative and vascular pathologies during the preclinical stages of dementia such as structural magnetic resonance imaging, positron emission tomography, and white matter hyperintensities. We also describe some emerging neuroimaging techniques such as arterial spin labeling, diffusion tensor imaging, and quantitative susceptibility mapping. Recent literature suggests that structural imaging may be the most sensitive and cost-effective marker to detect cognitive decline, while molecular positron emission tomography is primarily useful for detecting disease specific pathology later in the disease process. Currently, the presence of vascular disease on magnetic resonance imaging provides a potential target for optimizing vascular risk reduction strategies, and the presence of vascular disease may be useful when combined with molecular and metabolic markers of neurodegeneration for identifying the risk of cognitive impairment.

Status of genetic studies and breeding of Saccharina japonica in China

Saccharina japonica is one of the most important economic brown seaweeds.It is intensively cultivated on large scales in a number of Asian countries.The current annual,global production is about 8 million tons valued as about 4 million US dollars.Considerable efforts have been made to S.japonica in China since the 1950s on its cultivation.To further advance the cultivation of this species,detailed research of genetics and breeding studies are required.Recently,with the advancement of sequencing techniques,the genomics and comparative transcriptomics data were yielded,and quantitative trait locus(QTL)mapping has been conducted,along with genetic linkage maps constructed to this species.New strains have been bred and selected,with better characteristics,e.g.higher seawater temperature resistances and higher yields.In this review,we present the current status of genetic and breeding studies that have been performed to S.japonica in China,and provide guidelines for future developments in the areas of genetic selection and breeding for this species.

Morphine analgesia in male inbred genetic diversity mice recapitulates the among-individual variance in response to morphine in humans

Morphine is a widely used analgesic, but its use in clinical precision medicine is limited by the variance in response among individuals. Although previous studies have shown that individual differences in morphine can be explained in terms of pharmacodynamics and pharmacokinetics, genetic polymorphisms also play an important role. However, the genetic basis of different sensitivity and tolerance susceptibility to morphine remains ambiguous. Using 15 strains of inbred Genetic Diversity(GD) mice,a new resource with wide genetic and phenotypic variation, we demonstrated great variance in sensitivity to morphine analgesia and susceptibility to morphine tolerance between different GD strains. Among-i ndividual variance in response to morphine analgesia in the population can be modeled in GD mice. Two loci respectively may be associated with the among-i ndividual variance in morphine sensitivity and tolerance,confirming the role of genetic factors in among-i ndividual different responses to morphine. These results indicate that GD mice may be a potential tool for the identification of new biomarkers to improve the clinical administration of morphine.

Construction of high-density genetic linkage map of Pyropia yezoensis(Bangiales,Rhodophyta)and identifi cation of red color trait QTLs in the thalli

Pyropia yezoensis is an important macroalga because of its extensive global distribution and economic importance.Color is an important trait in the thalli of P.yezoensis,it is also an effective marker to identify the hybridization in genetic breeding.In this study,a high-density genetic linkage map was constructed based on high-throughput single nucleotide polymorphism(SNP)markers,and used for analyzing the quantitative trait loci(QTLs)of red color trait in the thalli of P.yezoensis.The conchospore undergoes meiosis to develop into an ordered tetrad,and each cell has a haploid phenotype and can grow into a single individual.Based on this theory,F1 haploid population was used as the mapping population.The map included 531 SNP markers,394.57 cM long on average distance of 0.74 cM.Collinear analysis of the genetic linkage map and the physical map indicated that the coverage between the two maps was 79.42%.Furthermore,QTL mapping identified six QTLs for the chromosomal regions associated with the red color trait of the thalli.The value of phenotypic variance explained(PVE)by an individual QTL ranged from 4.71%-63.11%.And QTL qRed-1-1,with a PVE of 63.11%,was considered the major QTL.Thus,these data may provide a platform for gene and QTL fine mapping,and marker-assisted breeding in P.yezoensis in the future.

Deep Learning‑Assisted Quantitative Susceptibility Mapping as a Tool for Grading and Molecular Subtyping of Gliomas

This study aimed to explore the value of deep learning(DL)-assisted quantitative susceptibility mapping(QSM)in glioma grading and molecular subtyping.Forty-two patients with gliomas,who underwent preoperative T2 fluid-attenuated inversion recovery(T2 FLAIR),contrast-enhanced T1-weighted imaging(T1WI+C),and QSM scanning at 3.0T magnetic resonance imaging(MRI)were included in this study.Histopathology and immunohistochemistry staining were used to determine glioma grades,and isocitrate dehydrogenase(IDH)1 and alpha thalassemia/mental retardation syndrome X-linked gene(ATRX)subtypes.Tumor segmentation was performed manually using Insight Toolkit-SNAP program(www.itksnap.org).An inception convolutional neural network(CNN)with a subsequent linear layer was employed as the training encoder to capture multi-scale features from MRI slices.Fivefold cross-validation was utilized as the training strategy(seven samples for each fold),and the ratio of sample size of the training,validation,and test dataset was 4:1:1.The performance was evalu-ated by the accuracy and area under the curve(AUC).With the inception CNN,single modal of QSM showed better perfor-mance in differentiating glioblastomas(GBM)and other grade gliomas(OGG,grade II–III),and predicting IDH1 mutation and ATRX loss(accuracy:0.80,0.77,0.60)than either T2 FLAIR(0.69,0.57,0.54)or T1WI+C(0.74,0.57,0.46).When combining three modalities,compared with any single modality,the best AUC/accuracy/F1-scores were reached in grading gliomas(OGG and GBM:0.91/0.89/0.87,low-grade and high-grade gliomas:0.83/0.86/0.81),predicting IDH1 mutation(0.88/0.89/0.85),and predicting ATRX loss(0.78/0.71/0.67).As a supplement to conventional MRI,DL-assisted QSM is a promising molecular imaging method to evaluate glioma grades,IDH1 mutation,and ATRX loss.

Identification and fine mapping of quantitative trait loci for seed vigor in germination and seedling establishment in rice

Seed vigor is an index of seed quality that is used to describe the rapid and uniform germination and the establish- ment of strong seedlings in any environmental conditions. Strong seed vigor in low-temperature germination conditions is particularly important in direct-sowing rice production systems. However, seed vigor has not been selected as an important breeding trait in traditional breeding programs due to its quantitative inherence. In this study, we identified and mapped eight quantitative trait loci （QTLs） for seed vigor by using a recombinant inbred population from a cross between rice （Oryza sativa L. ssp. indica） cultivars ZS97 and MH63. Conditional QTL analysis identified qSV-1, qSV-Sb, qSV-6a, qSV- 6b, and qSV-11 influenced seedling establishment and that qSV- 5a, qSV-Sc, and qSV-8 influenced only germination. Of these, qSV-1, qSV-Sb, qSV-6a, qSV-6b, and qSV-8 were low-tempera- ture-specific QTLs. Two major-effective QTLs, qSV-1, and qSV-5cwere narrowed down to 1.13-Mbp and 4oo-kbp genomic regions, respectively. The results provide tightly linked DNA markers for the marker-assistant pyramiding of multiple positive alleles for increased low-temperature germination seed vigor in both normal and environments.

Quantitative Trait Loci Mapping of Leaf Morphological Traits and Chlorophyll Content in Cultivated Tetraploid Cotton

Genetic mapping provides a powerful tool for quantitative trait loci （QTL） analysis at the molecular level. A simple sequence repeat （SSR） genetic map containing 590 markers and a BCI population from two cultivated tetraploid cotton （Gossypium hirsutum L.） cultivars, namely TM-1 and Hai 7124 （G. barbadense L.）, were used to map and analyze QTL using the composite interval mapping （CIM） method. Thirty one QTLs, 10 for lobe length, 13 for lobe width, six for lobe angle, and two for leaf chlorophyll content, were detected on 15 chromosomes or linkage groups at logarithm of odds （LOD）≥2.0, of which 15 were found for leaf morphology at LOD≥3.0. The genetic effects of the QTL were estimated. These results are fundamental for marker-assisted selection （MAS） of these traits in tetraploid cotton breeding.

Quantitative Trait Loci Mapping of Maize Yield and Its Components Under Different Water Treatments at Flowering Time

Drought or water stress is a serious agronomic problem resulting in maize （Zea mays L.） yield loss throughout the world. Breeding hybrids with drought tolerance is one important approach for solving this problem. However, lower efficiency and a longer period of breeding hybrids are disadvantages of traditional breeding programs. It is generally recognized that applying molecular marker techniques to traditional breeding programs could improve the efficiency of the breeding of drought-tolerant maize. To provide useful information for use in studies of maize drought tolerance, the mapping and tagging of quantitative trait loci （QTL） for yield and its components were performed in the present study on the basis of the principle of a mixed linear model. Two hundred and twenty-one recombinant inbred lines （RIL） of Yuyu 22 were grown under both well-watered and water-stressed conditions. In the former treatment group, plants were well irrigated, whereas those in the latter treatment group were stressed at flowering time. Ten plants of each genotype were grown in a row that was 3.00 m × 0.67 m （length × width）. The results show that a few of the QTL were the same （one additive QTL for ear length, two additive QTL and one pair of epistatic QTL for kernel number per row, one additive QTL for kernel weight per plant）, whereas most of other QTL were different between the two different water treatment groups. It may be that genetic expression differs under the two different water conditions. Furthermore, differences in the additive and epistatic QTL among the traits under water-stressed conditions indicate that genetic expression also differs from trait to trait. Major and minor QTL were detected for the traits, except for kernel number per row, under water-stressed conditions. Thus, the genetic mechanism of drought tolerance in maize is complex because the additive and epistatic QTL exist at the same time and the major and minor QTL all contribute to phenotype under water-stressed conditions. In particular, epidemic QTL under water-stressed conditions suggest that it is important to investigate the drought tolerance of maize from a genetic viewpoint.

Quantitative trait locus mapping with background control in genetic populations of clonal F_1 and double cross

In this study, we considered five categories of molecular markers in clonal F1 and double cross populations, based on the number of distinguishable alleles and the number of distinguishable genotypes at the marker locus. Using the completed linkage maps, incomplete and missing markers were imputed as fully informative markers in order to simplify the linkage mapping approaches of quantitative trait genes. Under the condition of fully informative markers, we demonstrated that dominance effect between the female and male parents in clonal F1 and double cross populations can cause the interactions between markers. We then developed an inclusive linear model that includes marker variables and marker interactions so as to completely control additive effects of the female and male parents, as well as the dominance effect between the female and male parents. The linear model was finally used for background control in inclusive composite interval mapping （ICIM） of quantitative trait locus （QTL）. The efficiency of ICIM was demonstrated by extensive simulations and by comparisons with simple interval mapping, multiple-QTLmodels and composite interval mapping. Finally, ICIM was applied in one actual double cross population to identify QTL on days to silking in maize.

Quantitative Trait Loci Mapping for Leaf Length and Leaf Width in Rice cv.IR64 Derived Lines

The present study was conducted to identify quantitative trait loci （QTLs） for leaf size traits in IR64 introgression lines （INLs）. For this purpose, selected F2 populations derived from crosses between recurrent parent IR64 and its derived INLs, unique for leaf length and leaf width, were used to confirm QTLs. A total of eight QTLs, mapped on three chromosomes, were identified for the four leaf size traits in six F2 populations. A QTL for leaf length, qLLnpt-1, in HKL69 was identified around simple sequence repeat （SSR） marker RM3709 on chromosome 1. Two QTLs for flag leaf length, qFLLnpt-2 and qFLLnpt-4, in HFG39 were indentified on chromosomes 2 and 4, respectively. For flag leaf width, a QTL, qFLWnpt-4, in HFG39 was identified around RM17483 on chromosome 4. While another QTL for flag leaf width, qFLWnpt-1, in HFG27 was identified around RM3252 on chromosome 1. A QTL for leaf width, qLWnpt-2, in HKL75 was identified around RM7451 on chromosome 2. For leaf width, two QTLs, qLWnpt-4a, qLWnpt-4b, in HKL48 and HKL99 were identified around RM7208 and RM6909, respectively on chromosome 4. Results from this study suggest the possibilities to use marker-assisted selection and pyramiding these QTLs to improve rice water productivity.

IMPROVED HARMONIC INCOMPATIBILITY REMOVAL FOR SUSCEPTIBILITY MAPPING VIA REDUCTION OF BASIS MISMATCH

In quantitative susceptibility mapping(QSM),the background field removal is an essential data acquisition step because it has a significant effect on the restoration quality by generating a harmonic incompatibility in the measured local field data.Even though the sparsity based first generation harmonic incompatibility removal(1GHIRE)model has achieved the performance gain over the traditional approaches,the 1GHIRE model has to be further improved as there is a basis mismatch underlying in numerically solving Poisson’s equation for the background removal.In this paper,we propose the second generation harmonic incompatibility removal(2GHIRE)model to reduce a basis mismatch,inspired by the balanced approach in the tight frame based image restoration.Experimental results shows the superiority of the proposed 2GHIRE model both in the restoration qualities and the computational efficiency.