scholarly journals Genetic Dissection of Seed Storability and Validation of Candidate Gene Associated with Antioxidant Capability in Rice (Oryza sativa L.)

2019 ◽  
Vol 20 (18) ◽  
pp. 4442 ◽  
Author(s):  
Yuan ◽  
Fan ◽  
Xia ◽  
Ding ◽  
Tian ◽  
...  
Keyword(s):  
Candidate Gene ◽  
Oryza Sativa L ◽  
Recombinant Inbred Lines ◽  
Physiological Characteristic ◽  
Genetic Dissection ◽  
Isogenic Line ◽  
Single Nucleotide ◽  
F2 Population ◽  
Germination Ability ◽  
Seed Storability

Seed storability, defined as the ability to remain alive during storage, is an important agronomic and physiological characteristic, but the underlying genetic mechanism remains largely unclear. Here, we report quantitative trait loci (QTLs) analyses for seed storability using a high-density single nucleotide polymorphism linkage map in the backcross recombinant inbred lines that was derived from a cross of a japonica cultivar, Nipponbare, and an indica cultivar, 9311. Seven putative QTLs were identified for seed storability under natural storage, each explaining 3.6–9.0% of the phenotypic variation in this population. Among these QTLs, qSS1 with the 9311 alleles promoting seed storability was further validated in near-isogenic line and its derived-F2 population. The other locus (qSS3.1) for seed storability colocalized with a locus for germination ability under hydrogen peroxide, which is recognized as an oxidant molecule that causes lipid damage. Transgenic experiments validated that a candidate gene (OsFAH2) resides the qSS3.1 region controlling seed storability and antioxidant capability. Overexpression of OsFAH2 that encodes a fatty acid hydroxylase reduced lipid preoxidation and increased seed storability. These findings provide new insights into the genetic and physiological bases of seed storability and will be useful for the improvement of seed storability in rice.

scholarly journals Genetic dissection of heterosis of indica–japonica by introgression line, recombinant inbred line and their testcross populations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wenqing Yang ◽  
Fan Zhang ◽  
Sundus Zafar ◽  
Junmin Wang ◽  
Huajin Lu ◽  
...  
Keyword(s):  
Grain Yield ◽  
Recombinant Inbred ◽  
Genetic Basis ◽  
Recombinant Inbred Lines ◽  
Introgression Line ◽  
Successful Implementation ◽  
Genetic Dissection ◽  
Single Nucleotide ◽  
Panicle Number ◽  
Main Effect

AbstractThe successful implementation of heterosis in rice has significantly enhanced rice productivity, but the genetic basis of heterosis in rice remains unclear. To understand the genetic basis of heterosis in rice, main-effect and epistatic quantitative trait loci (QTLs) associated with heterosis for grain yield-related traits in the four related rice mapping populations derived from Xiushui09 (XS09) (japonica) and IR2061 (indica), were dissected using single nucleotide polymorphism bin maps and replicated phenotyping experiments under two locations. Most mid-parent heterosis of testcross F1s (TCF1s) of XS09 background introgression lines (XSILs) with Peiai64S were significantly higher than those of TCF1s of recombinant inbred lines (RILs) with PA64S at two locations, suggesting that the effects of heterosis was influenced by the proportion of introgression of IR2061’s genome into XS09 background. A total of 81 main-effect QTLs (M-QTLs) and 41 epistatic QTLs were identified for the phenotypic variations of four traits of RILs and XSILs, TCF1s and absolute mid-parent heterosis in two locations. Furthermore, overdominance and underdominance were detected to play predominant effects on most traits in this study, suggesting overdominance and underdominance as well as epistasis are the main genetic bases of heterosis in rice. Some M-QTLs exhibiting positive overdominance effects such as qPN1.2, qPN1.5 and qPN4.3 for increased panicle number per plant, qGYP9 and qGYP12.1 for increased grain yield per plant, and qTGW3.4 and qTGW8.2 for enhanced 1000-grain weight would be highly valuable for breeding to enhance grain yield of hybrid rice by marker-assisted selection.

scholarly journals Dissection of Genetic Basis Underpinning Kernel Weight-Related Traits in Common Wheat

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 713
Author(s):  
Shunda Li ◽  
Liang Wang ◽  
Yaning Meng ◽  
Yuanfeng Hao ◽  
Hongxin Xu ◽  
...  
Keyword(s):  
Recombinant Inbred Lines ◽  
Wheat Yield ◽  
Snp Array ◽  
Kernel Weight ◽  
Yield Potential ◽  
Phenotypic Variance ◽  
Genetic Dissection ◽  
Single Nucleotide ◽  
Grain Width ◽  
Potential Improvement

Genetic dissection kernel weight-related traits is of great significance for improving wheat yield potential. As one of the three major yield components of wheat, thousand kernel weight (TKW) was mainly affected by grain length (GL) and grain width (GW). To uncover the key loci for these traits, we carried out a quantitative trait loci (QTL) analysis of an F6 recombinant inbred lines (RILs) population derived from a cross of Henong 5290 (small grain) and 06Dn23 (big grain) with a 50 K single nucleotide polymorphism (SNP) array. A total of 17 stable and big effect QTL, including 5 for TKW, 8 for GL and 4 for GW, were detected on the chromosomes 1B, 2A, 2B, 2D, 4B, 5A, 6A and 6D, respectively. Among these, there were two co-located loci for three traits that were mapped on the chromosome 4BS and 6AL. The QTL on 6AL was the most stable locus and explained 15.4–24.8%, 4.1–8.8% and 15.7–24.4% of TKW, GW and GL variance, respectively. In addition, two more major QTL of GL were located on chromosome arm 2BL and 2DL, accounting for 9.7–17.8% and 13.6–19.8% of phenotypic variance, respectively. In this study, we found one novel co-located QTL associated with GL and TKW in 2DL, QGl.haaf-2DL.2/QTkw.haaf-2DL.2, which could explain 13.6–19.8% and 9.8–10.7% phenotypic variance, respectively. Genetic regions and linked markers of these stable QTL will help to further refine mapping of the corresponding loci and marker-assisted selection (MAS) breeding for wheat grain yield potential improvement.

scholarly journals Identification and Validation of a QTL for Bacterial Leaf Streak Resistance in Rice (Oryza sativa L.) against Thai Xoc Strains

Genes ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1587
Author(s):  
Tripop Thianthavon ◽  
Wanchana Aesomnuk ◽  
Mutiara K. Pitaloka ◽  
Wannapa Sattayachiti ◽  
Yupin Sonsom ◽  
...  
Keyword(s):  
Candidate Gene ◽  
Oryza Sativa L ◽  
Genomic Region ◽  
Phenotypic Variance ◽  
Potential Candidate ◽  
Nucleotide Polymorphisms ◽  
Bacterial Leaf Streak ◽  
Rice Varieties ◽  
F2 Population ◽  
Specific Pcr

Rice is one of the most important food crops in the world and is of vital importance to many countries. Various diseases caused by fungi, bacteria and viruses constantly threaten rice plants and cause yield losses. Bacterial leaf streak disease (BLS) caused by Xanthomonas oryzae pv. oryzicola (Xoc) is one of the most devastating rice diseases. However, most modern rice varieties are susceptible to BLS. In this study, we applied the QTL-seq approach using an F2 population derived from the cross between IR62266 and Homcholasit (HSC) to rapidly identify the quantitative trait loci (QTL) that confers resistance to BLS caused by a Thai Xoc isolate, SP7-5. The results showed that a single genomic region at the beginning of chromosome 5 was highly associated with resistance to BLS. The gene xa5 was considered a potential candidate gene in this region since most associated single nucleotide polymorphisms (SNPs) were within this gene. A Kompetitive Allele-Specific PCR (KASP) marker was developed based on two consecutive functional SNPs in xa5 and validated in six F2 populations inoculated with another Thai Xoc isolate, 2NY2-2. The phenotypic variance explained by this marker (PVE) ranged from 59.04% to 70.84% in the six populations. These findings indicate that xa5 is a viable candidate gene for BLS resistance and may help in breeding programs for BLS resistance.

scholarly journals Genetic Dissection of Seed Dormancy in Rice (Oryza sativa L.) by Using Two Mapping Populations Derived from Common Parents

Rice ◽  
2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Chaopu Zhang ◽  
Zhiyang Yuan ◽  
Yuntong Wang ◽  
Wenqiang Sun ◽  
Xinxin Tang ◽  
...  
Keyword(s):  
Oryza Sativa ◽  
Seed Dormancy ◽  
Oryza Sativa L ◽  
Genetic Dissection ◽  
Mapping Populations

scholarly journals Genetic Dissection of an Elite Rice Hybrid Revealed That Heterozygotes Are Not Always Advantageous for Performance

Genetics ◽  
2002 ◽  
Vol 162 (4) ◽  
pp. 1885-1895
Author(s):  
J P Hua ◽  
Y Z Xing ◽  
C G Xu ◽  
X L Sun ◽  
S B Yu ◽  
...  
Keyword(s):  
Field Trials ◽  
Genetic Dissection ◽  
F2 Population ◽  
Genetic Components ◽  
Large Numbers ◽  
Marker Loci ◽  
Component Traits ◽  
Single Locus Analysis ◽  
Immortalized F2 ◽  
Heterotic Hybrid

Abstract We introduced an experimental design that produced an “immortalized F2” population allowing for complete dissection of genetic components underlying quantitative traits. Data for yield and three component traits of the immortalized F2 were collected from replicated field trials over 2 years. Using 231 marker loci, we resolved the genetic effects into individual components and assessed relative performance of all the genotypes at both single- and two-locus levels. Single-locus analysis detected 40 QTL for the four traits. Dominance effects for about one-half of the QTL were negative, resulting in little “net” positive dominance effect. Correlation between genotype heterozygosity and trait performance was low. Large numbers of digenic interactions, including AA, AD, and DD, were detected for all the traits, with AA as the most prevalent interaction. Complementary two-locus homozygotes frequently performed the best among the nine genotypes of many two-locus combinations. While cumulative small advantages over two-locus combinations may partly explain the genetic basis of heterosis of the hybrid as double heterozygotes frequently demonstrated marginal advantages, double heterozygotes were never the best genotypes in any of the two-locus combinations. It was concluded that heterozygotes were not necessarily advantageous for trait performance even among genotypes derived from such a highly heterotic hybrid.

scholarly journals Molecular genetics of bipolar disorder

2001 ◽  
Vol 178 (S41) ◽  
pp. s128-s133 ◽  
Author(s):  
Nick Craddock ◽  
Ian Jones
Keyword(s):  
Bipolar Disorder ◽  
Candidate Gene ◽  
Molecular Genetics ◽  
Ethical Issues ◽  
Association Studies ◽  
Single Gene ◽  
Molecular Genetic ◽  
Genetic Dissection ◽  
Adoption Studies ◽  
Candidate Gene Association

BackgroundA robust body of evidence from family, twin and adoption studies demonstrates the importance of genes in the pathogenesis of bipolar disorder. Recent advances in molecular genetics have made it possible to identify these susceptibility genes.AimsTo present an overview for clinical psychiatrists.MethodReview of current molecular genetics approaches and emerging findings.ResultsOccasional families may exist in which a single gene plays a major role in determining susceptibility, but the majority of bipolar disorder involves more complex genetic mechanisms such as the interaction of multiple genes and environmental factors. Molecular genetic positional and candidate gene approaches are being used for the genetic dissection of bipolar disorder. No gene has yet been identified but promising findings are emerging. Regions of interest include chromosomes 4p16, 12q23–q24, 16p13, 21q22, and Xq24–q26. Candidate gene association studies are in progress but no robust positive findings have yet emerged.ConclusionIt is almost certain that over the next few years the identification of bipolar susceptiblity genes will have a major impact on our understanding of disease pathophysiology. This is likely to lead to major improvements and treatment in patient care, but will also raise important ethical issues.

Sign in / Sign up

Export Citation Format

Share Document