Influence of Multi-Gene Allele Combinations on Grain Size of Rice and Development of a Regression Equation Model to Predict Grain Parameters

Lee, Chan-Mi,Park, Jonghwa,Kim, Backki,Seo, Jeonghwan,Lee, Gileung,Jang, Su,Koh, Hee-Jong Springer US 2015 Rice Vol.8 No.-

<P><B>Background</B></P><P>Grain size is one of the key factors determining yield and quality in rice. A large number of genes are involved in the regulation of grain size parameters such as grain length and grain width. Different alleles of these genes have different impacts on the grain size traits under their control. However, the combined influence of multiple alleles of different genes on grain size remains to be investigated. Six key genes known to influence grain size were investigated in this study: <I>GS3</I>, <I>GS5</I>, <I>GS6</I>, <I>GW2</I>, <I>qSW5</I>/<I>GW5</I>, and <I>GW8</I>/<I>OsSPL16.</I> Allele and grain measurement data were used to develop a regression equation model that can be used for molecular breeding of rice with desired grain characteristics.</P><P><B>Results</B></P><P>A total of 215 diverse rice germplasms, which originated from or were developed in 28 rice-consuming countries, were used in this study. Genotyping analysis demonstrated that a relatively small number of allele combinations were preserved in the diverse population and that these allele combinations were significantly associated with differences in grain size. Furthermore, in several cases, variation at a single gene was sufficient to influence grain size, even when the alleles of other genes remained constant. The data were used to develop a regression equation model for prediction of rice grain size, and this was tested using data from a further 34 germplasms. The model was significantly correlated with three of the four grain size-related traits examined in this study.</P><P><B>Conclusion</B></P><P>Rice grain size is strongly influenced by specific combinations of alleles from six different genes. A regression equation model developed from allele and grain measurement data can be used in rice breeding programs for the development of new rice varieties with desired grain size and shape.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (doi:10.1186/s12284-015-0066-1) contains supplementary material, which is available to authorized users.</P>

자포니카 벼 입형 다양화 육종소재 개발 및 특성 분석

박현수(Hyun-Su Park),백만기(Man-Kee Baek),남정권(Jeong-Kwon Nam),신운철(Woon-Cheol Shin),정종민(Jong-Min Jeong),이건미(Gun-Mi Lee),박슬기(Seul-Gi Park),김춘송(Choon-Song Kim),조영찬(Young-Chan Cho),김보경(Bo-Kyeong Kim) 한국육종학회 2017 한국육종학회지 Vol.49 No.4

To diversify the grain size and shape of japonica rice, we developed the Breeding Materials with Diverse Grain Size and Shape (BM_DGS) and characterized the grain and yield-related traits. We used the donor parents Jizi1560 and Jizi1581, japonica germplasm with extremely large grain size. Four cross combinations between the each donor parents and Korean high yielding japonica rice cultivars, Deuraechan and Boramchan, were constructed and anther culture method was applied. Among 290 doubled haploid lines, we selected 91 elite lines with diverse grain size and shape and designated to the BM_DGS. The grain size and shape of BM_DGS exhibited beyond the characteristics of previously developed Korean rice cultivars. The alleles of major grain-related genes, GW2, GS3, and qSW5, in BM_DGS showed two types, wild type or loss-of-function mutant type. The loss-of-function mutant alleles, gw2, gs3, and qsw5, had an effect on increasing grain size. The phenotypic variation of grain length was mostly controlled by GS3 alleles, and grain width and thickness were influenced by the combinations of GW2 and qSW5 alleles. 1,000-grain weight was determined by the combinations of GW2, GS3, and qSW5. The grain-related genes influenced the phenotypic variation of yield-related traits. The result of this study could be useful to elucidate the relationship between the grain-related genes and agronomic traits. And the BM_DGS are being utilized in the breeding programs to diversify the grain size and shape in japonica rice.

Effect of grain size on residual stress in AlSi10MnMg alloy

전민정,이은경 한국마린엔지니어링학회 2023 한국마린엔지니어링학회지 Vol.47 No.4

The effect of varying the grain size on the residual stress in AlSi10MnMg alloys prepared at various cooling rates was examined. The specimens with different initial grain sizes were manufactured by high-pressure die casting (HPDC) and gravity die casting (GDC) under heat treatment at 500 °C for 2 h, followed by furnace cooling and water quenching to control the variables that could affect the residual stress or induce microstructural changes. The average grain size of the non-heat-treated as-cast HPDC speci-men was approximately 30 times smaller than that of the as-cast GDC specimen, and the residual stress of the large-grain GDC speci-men was approximately 20 MPa larger. The grain size of the furnace-cooled GDC specimen was approximately 50 times larger than the average grain size of the furnace-cooled HPDC specimen, and the largest difference in the residual stress was approximately 40 MPa. The average grain sizes of the water-quenched GDC and HPDC specimens differed by approximately ten-fold, where the residual stress in the water-quenched GDC specimen was approximately 8 MPa higher. The larger the grain size, the more easily the low-angle grain boundaries are penetrated by the potential. Therefore, a larger the grain size leads to better distribution of the low-angle grain systems; thus, numerous dislocations were distributed inside and around the grain. The grain boundaries and dislocations that were highly aggregated inside the grain influenced the residual stress.

대립벼 1호의 종자중에 관여하는 유전자 분석

심규찬,강주원,이현숙,안상낙 한국육종학회 2016 한국육종학회지 Vol.48 No.3

Grain size has a great impact on rice grain yield and is controlled by quantitative trait loci (QTL). Daeribbyeo 1 with big grain is widely used for genetic materials to develop varieties with diverse grain size. This study was conducted to identify genes controlling grain size traits of Daeribbyeo 1. An F2:3 population derived from a cross between two japonica cultivars, Boseogheugchal and Daeribbyeo1, was used to identify QTL controlling grain shape traits. A total of 284 F2 plants were measured for grain shape traits, grain length (GL), grain width (GW), grain thickness (GT), 1,000 grain weight (TGW), and two morphological traits, pericarp color and waxy endosperm. Sixty F3 lines were selected based on the grain shape traits and marker genotypes and evaluated for grain shape traits. For marker analysis, SSR markers tightly linked to five known grain size genes and two QTLs were selected and used for genotyping. A total of 11 QTLs detected on chromosomes 2, 3, 4 and 6 explained phenotypic variation from 3.9% to 59.3%. qTGW2, qGW2 and qGT2 were detected in the same region between RM12811-RM12837 that are tightly linked with GW2 gene. qTGW3 and qGL3 were detected near GS3 gene. To know whether Daeribbyeo 1 has the same mutations in GW2 and GS3 as the various grain-size genotypes, GW2 and GS3 of two parents were sequenced. Daeribbyeo 1 had the same one base (A) deletion at a position 316 as ‘WY3’ in GW2 which results in the loss of function of GW2 gene. Boseogheugchal showed a C-to-A nonsense mutation in the second exon of GS3 gene that increased grain length. Interaction between GW2 and GS3 was not significant indicating that two genes controlled grain-size traits in additive pathway. The results from this study indicate that three QTLs GW2, qGT4 and qGL6 are associated with the grain size variation in Daeribbyeo 1 with GW2 as the major QTL.

Specimen size effects on the weakening of a bulk metastable austenitic alloy

Shin, C.,Lim, S.,Jin, H.h.,Hosemann, P.,Kwon, J. Elsevier Sequoia 2015 Materials science & engineering Structural materia Vol.622 No.-

In this work, we are investigating the scaling effects on an austenitic stainless steel with changing grain size using microcompression testing. It is our aim to evaluate at what sample-to-grain size ratio the mechanical properties such as yield stress deviate from the macroscopically determined data. It was found that decreased yield stresses with decreasing specimen size (weakening) occur during the microcompression. The weakening was observed when the diameter-to-grain size ratio (D/d) dropped below a critical value. The effect of the grain size on the critical value, above which the bulk property can be obtained, was systematically investigated utilizing a wide range of D/d values (0.5-30) for specimens with a grain size ranging from 0.3 to 2μm. It was found that the critical D/d value decreases with increasing grain size. A simple analytical model was developed, which is applicable to both micropillar and tensile tests. Comparison of the model equations with experimental data showed that the reduction in yield stress with sample size can be associated with the weaker near-surface zone, which has a reduced strength compared to the specimen interior zone. Furthermore, this study suggests that the size of the near-surface zone may be related to the dislocation structures in near-surface grains, and therefore the overall behavior is governed by the grain size and stacking fault energy.

복합조직 강의 파괴 거동에 대한 페라이트 입도의 영향

윤재형(Jaehyung Yun),오환섭(Hwansup Oh) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.12

In this study, grain size of ferrite and size of grain in SM20C were changed after preprocessing with 920℃ and 1150℃. Two specimens with different grain size gained Martensite in case-hardening layer through high frequency surface heat treatment. Other specimens(920℃,1150℃ heat treatment) that Ferrite and Pearlite’s grain size and composition of metallic structure are different were used to watch fracture behavior depending on size of grain and composite grain. A ferrite’s grain framed in some martensite’s grain has residual stress. in other words residual stress was made from composite grain like martensite. and residual stress influenced fracture behavior. So, this study investigated of the fracture behavior from A grain included residual stress from composite grain, grain size.

Influence of Grain Size Deviation on the Characteristics of Poly-Si Thin Film Transistor

Takashi Noguchi,HyunMo Koo,HongSock Choi 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.2

The influence of grain size deviation on the device characteristics of thin film transistors (TFTs) was investigated by using the defect and grain model. By varying the deviation of the grain size in poly-Si film relating to the channel size of the device, the deviations of the S factor, i.e., the gate voltage swing, which affects the threshold voltage and the drain current, were evaluated. From the calculation results, as the deviation of the grain size increases, the uniformity of the device characteristics degrades drastically. As the channel size decreases, the uniformity of the device characteristics degrades drastically even for the same deviation of grain size. If high-performance, uniform TFTs are realized, it is important to control the deviation of the grain size and the number of grains contained in a channel, as well as the grain size itself.

Ti 첨가강의 Ti와 C 함량에 따른 초기 오스테나이트 입도 변화

김우진,강남현,도형협,김성주,남대근,조경목,Kim, Woo-Jin,Kang, Nam-Hyun,Kim, Sung-Ju,Do, Hyung-Hyup,Nam, Dae-Geun,Cho, Kyung-Mox 한국재료학회 2011 한국재료학회지 Vol.21 No.4

Prior austenite grain size plays an important role in the production of high strength hot-rolled steel. This study investigated the effect of Ti and C contents on the precipitates and prior austenite grain size. Steel with no Ti solutes had prior austenite grain size of about 620 ${\mu}m$. The addition of Ti ~ 0.03 wt.% and 0.11 wt.% reduced the prior austenite grain size to 180 ${\mu}m$ and 120 ${\mu}m$, respectively. The amount of Ti required to significantly decrease the prior austenite grain size was in the range of 0.03 wt.%. However, the amount of carbon required to significantly decrease the prior austenite grain size was not present from 0.04 wt.% to 0.12 wt.%. Oxides of Ti ($Ti_2O_3$) were observed as the Ti content increased to 0.03 wt.%. The specimen containing 0.11 wt.% of Ti exhibited the complex carbides of (Ti, Nb) C. The formation of Ti precipitates was critical to reduce the prior austenite grain size. Furthermore, the consistency of prior austenite grain size increased as the carbon and Ti contents increased. During the reheating process of hot-rolled steel, the most critical factor for controlling the prior austenite grain size seems to be the presence of Ti precipitates.

기계학습을 이용한 색상형 미세조직의 결정립 크기 측정

정준호,김희수 대한금속·재료학회 2023 대한금속·재료학회지 Vol.61 No.5

We constructed a convolutional neural network to estimate average grain size from microstructureimages. In the previous study from our research group, the network was trained using GB-type images inwhich the grain matrix and grain boundary were represented in white and black, respectively. The model wellestimated the same GB-type images, but did not properly predict CL-type images where grain boundarieswere defined by color contrast between grains. In the present study, the convolutional neural network wastrained using CL-type microstructure images, and evaluated the average grain size, for comparison with theprevious GB-type model. The relationship between the microstructure image and the average grain size wasdetermined using regression rather than classification. Then, the results were compared with the previousones. Finally, the proposed approach was used for actual microstructural image analysis. Mid-layer imageswere extracted to examine how the network recognizes the characteristics of microstructures, such as graincolor and grain boundary. Like the previous GB-type model, the present CL-type model seems to estimatethe average grain size from the curvature of the grain boundary through edge detection of the grainboundaries. However, the GB- and CL-type models only properly predicted the grain size from the same kindof images as the training data, because the definitions of the grain boundaries of the two models weredifferent.

Al-Mg-X (X=Cr, Si)합금의 기계적성질에 미치는 결정립크기와 시효조건의 영향

한창석 ( Chang-suk Han ),이찬우 ( Chan-woo Lee ) 한국열처리공학회 2023 熱處理工學會誌 Vol.36 No.2

In this study, the mechanical properties of the Al-Mg-X (X=Cr, Si) alloy, which clearly showed the influence of the specimen and grain size, were investigated by changing the specimen size extensively. In addition, the effect on the specimen size, grain size and aging condition on the mechanical properties of the grain refining alloy according to the addition of Cr was clarified, and the relationship between these factors was studied. As the specimen size decreased, the yield stress decreased and the fracture elongation increased. This change was evident in alloys with coarse grain sizes. Through FEM analysis, it was confirmed that the plastic deformation was localized in the parallel part of specimen S2. Therefore, when designing a tensile specimen of plate material, the W/L balance should be considered along with the radius of curvature of the shoulder. In the case of under-aged materials of alloys with coarse grain size, the fracture pattern changed from intergranular fracture to transgranular fracture as W/d decreased, and δ increased. This is due to the decrease in the binding force between grains due to the decrease in W. In the specimen with W/d > 40 or more, intergranular fracture occurred, and local elongation did not appear. Under-aged materials of alloys with fine grain size always had transgranular fracture over a wide range of W/d = 70~400. As W/d decreased, δ increased, but the change was not as large as that of alloys with coarse grain sizes. Compared to the under-aged material, the peak-aged material did not show significant dependence on the specimen size of σ_0.2 and δ. (Received February 10, 2023; Revised March 15, 2023; Accepted March 15, 2023)