Pasting properties are among the most important characteristics of starch, determining its applications in food processing and other industries. Pasting temperature derived from the Rapid Visco-analyser （RVA） （Newp...Pasting properties are among the most important characteristics of starch, determining its applications in food processing and other industries. Pasting temperature derived from the Rapid Visco-analyser （RVA） （Newport Scientific）, in most cases, is overestimated by the Thermocline for Windows software program. Here, two methods facilitating accurate measurement of pasting temperature by RVA were described. One is to change parameter setting to ＇screen＇ the true point where the pasting viscosity begins to increase, the other is to manually record the time （T1） when the pasting viscosity begins to increase and calculate the pasting temperature with the formula of （45/3.8）×（T1-1）＋50 for rice flour. The latter method gave a manually determined pasting temperature which was significantly correlated with the gelatinization temperature measured by differential scanning calorimetry.展开更多
Phospholipids are a major kind of lipids in rice grains and have fundamental nutritional andfunctional benefits to the plant. Their lyso forms （lysophospholipids, LPLs） often form inclusion complexeswith amylose or ...Phospholipids are a major kind of lipids in rice grains and have fundamental nutritional andfunctional benefits to the plant. Their lyso forms （lysophospholipids, LPLs） often form inclusion complexeswith amylose or independently influence the physicochemical and functional properties of rice starch.However, the genetic basis for LPL synthesis in rice endosperm is largely unknown. Here, we performeda preliminary association test of 13 LPL compositions among 20 rice accessions, and identified 22putative main-effect quantitative trait loci responsible for all LPLs except for LPC14：0 and LPE14：0. Fivederived cleaved amplified polymorphic sequences and one insertion/deletion marker for threeLPL-synthesis-related candidate genes were developed. Association analysis revealed two markerssignificantly associated with starch LPL traits. These results provide an insight into the genetic basis ofphospholipid biosynthesis in rice and may contribute to the rice quality breeding programs usingfunctional markers.展开更多
Agronomic traits are important determinants to rice yield, which are controlled by complex genetic factors as well as genotype by environment （G × E） interaction effects. The G × E effects for agronomic tr...Agronomic traits are important determinants to rice yield, which are controlled by complex genetic factors as well as genotype by environment （G × E） interaction effects. The G × E effects for agronomic traits of rice have been dissected with various approaches, but not with the current available approach, the association studies. In this study, a total of 32 655 single nucleotide polymorphisms were used to carry out associations with 14 agronomic traits among 20 rice accessions in two environments. The G × E interaction effects for all the agronomic traits were at highly significant levels （P〈0.01）, accounting for 3.4%-22.3% of the total sum of squares except for the length of brown rice. Twenty three putative quantitative trait loci （QTLs）, including five previously known and several new promising associations, were identified for 10 of 14 traits. Analysis of the relationships between the traits for which QTLs and the genotype effects could be identified suggested that the higher the genotypic effect, the higher the possibility to identify QTLs for the given trait. The new QTLs detected in this study will facilitate dissection of the complex agronomic traits and may give insight into the G × E effects with association mapping.展开更多
A total of 105 transgenic dce lines independently transformed with a pea ferritin gene （Fer） were previously obtained. After seven generations of selfing and β-glucuronidase （GUS） assisted selection, 82 transgeni...A total of 105 transgenic dce lines independently transformed with a pea ferritin gene （Fer） were previously obtained. After seven generations of selfing and β-glucuronidase （GUS） assisted selection, 82 transgenic lines with stable agronomic traits were got. Among the 82 transgenic lines, two high-iron transgenic rice lines Fer34 and Fer65, with the iron contents in the milled rice being 4.82 and 3.46 times of that of the wild type Xiushui 11, respectively were identified. In the two transgenic lines, the exogenous Fer gene was highly expressed, and inherited as a single locus. The transgene had no negative effect on the agronomic traits of rice plant, other mineral nutritional components, appearance quality and eating quality of the milled rice, indicating that these two lines were elite high-iron breeding lines. Furthermore, the practical application and further studies facilitating utilization of the two elite breeding lines were discussed.展开更多
High yield in rice mainly depends on large grain weight, ideal plant architecture and proper flowering time adapting to various geographic regions. To help achieve higher yield, phenotype variations of heading date（H...High yield in rice mainly depends on large grain weight, ideal plant architecture and proper flowering time adapting to various geographic regions. To help achieve higher yield, phenotype variations of heading date（HD）, plant architecture and grain shape in a panel of 416 rice accessions were investigated in this study. A total of 143 markers including 100 simple sequence repeat（SSR） markers and 43 gene-tagged markers were employed in association mapping to detect quantitative trait loci（QTL） responsible for these variations. Among the 7 subpopulations, POP5 in japonica group showed the largest values of HD and grain width（GW）, but the smallest values of grain length（GL） and grain length to width ratio（GLW）. Among the six indica groups, POP7 had the largest values of HD, GL, GLW, and 1 000-grain weight（TGW）. A total of 27 QTLs were detected underlying these phenotypic variations in single year, while 12 of them could be detected in 2006 and 2007. GS3 marker was closely associated with GL, GW and GLW, and widely distributed in different groups. The starch synthesis related gene markers, SSI, SSIIa, SBE1, AGPL4, and ISA1, were linked to plant height（PH）, panicle length（PL）, flag leaf length（FLL）, GW, and GLW. The SSR markers, RM267, RM340 and RM346, were linked to at least two traits. Therefore, these new markers will probably be used to improve rice grain yield or plant architecture when performing marker-assisted selection of proper alleles.展开更多
基金This research was financially supported in part by the National High Technology Development Project of China(Grant No.2006AA10Z193)the National Natural Science Foundation of China(Grant No.30300227)the Science and Technology Department of Zhejiang Province(Grant No.2007C32014).
文摘Pasting properties are among the most important characteristics of starch, determining its applications in food processing and other industries. Pasting temperature derived from the Rapid Visco-analyser （RVA） （Newport Scientific）, in most cases, is overestimated by the Thermocline for Windows software program. Here, two methods facilitating accurate measurement of pasting temperature by RVA were described. One is to change parameter setting to ＇screen＇ the true point where the pasting viscosity begins to increase, the other is to manually record the time （T1） when the pasting viscosity begins to increase and calculate the pasting temperature with the formula of （45/3.8）×（T1-1）＋50 for rice flour. The latter method gave a manually determined pasting temperature which was significantly correlated with the gelatinization temperature measured by differential scanning calorimetry.
基金financially supported by the Fundamental Research Funds for the Central Universities at Zhejiang University,Hangzhou,China(Grant No.2016XZZX001-09)
文摘Phospholipids are a major kind of lipids in rice grains and have fundamental nutritional andfunctional benefits to the plant. Their lyso forms （lysophospholipids, LPLs） often form inclusion complexeswith amylose or independently influence the physicochemical and functional properties of rice starch.However, the genetic basis for LPL synthesis in rice endosperm is largely unknown. Here, we performeda preliminary association test of 13 LPL compositions among 20 rice accessions, and identified 22putative main-effect quantitative trait loci responsible for all LPLs except for LPC14：0 and LPE14：0. Fivederived cleaved amplified polymorphic sequences and one insertion/deletion marker for threeLPL-synthesis-related candidate genes were developed. Association analysis revealed two markerssignificantly associated with starch LPL traits. These results provide an insight into the genetic basis ofphospholipid biosynthesis in rice and may contribute to the rice quality breeding programs usingfunctional markers.
基金supported by the Special Fund for Agro-Scientific Research in the Public Interest from the Ministry of Agriculture, China (Grant No. 201103007)
文摘Agronomic traits are important determinants to rice yield, which are controlled by complex genetic factors as well as genotype by environment （G × E） interaction effects. The G × E effects for agronomic traits of rice have been dissected with various approaches, but not with the current available approach, the association studies. In this study, a total of 32 655 single nucleotide polymorphisms were used to carry out associations with 14 agronomic traits among 20 rice accessions in two environments. The G × E interaction effects for all the agronomic traits were at highly significant levels （P〈0.01）, accounting for 3.4%-22.3% of the total sum of squares except for the length of brown rice. Twenty three putative quantitative trait loci （QTLs）, including five previously known and several new promising associations, were identified for 10 of 14 traits. Analysis of the relationships between the traits for which QTLs and the genotype effects could be identified suggested that the higher the genotypic effect, the higher the possibility to identify QTLs for the given trait. The new QTLs detected in this study will facilitate dissection of the complex agronomic traits and may give insight into the G × E effects with association mapping.
文摘A total of 105 transgenic dce lines independently transformed with a pea ferritin gene （Fer） were previously obtained. After seven generations of selfing and β-glucuronidase （GUS） assisted selection, 82 transgenic lines with stable agronomic traits were got. Among the 82 transgenic lines, two high-iron transgenic rice lines Fer34 and Fer65, with the iron contents in the milled rice being 4.82 and 3.46 times of that of the wild type Xiushui 11, respectively were identified. In the two transgenic lines, the exogenous Fer gene was highly expressed, and inherited as a single locus. The transgene had no negative effect on the agronomic traits of rice plant, other mineral nutritional components, appearance quality and eating quality of the milled rice, indicating that these two lines were elite high-iron breeding lines. Furthermore, the practical application and further studies facilitating utilization of the two elite breeding lines were discussed.
基金financially supported by the Fundamental Research Funds for the Central Universities at Zhejiang University, China (2016XZZX001-09)
文摘High yield in rice mainly depends on large grain weight, ideal plant architecture and proper flowering time adapting to various geographic regions. To help achieve higher yield, phenotype variations of heading date（HD）, plant architecture and grain shape in a panel of 416 rice accessions were investigated in this study. A total of 143 markers including 100 simple sequence repeat（SSR） markers and 43 gene-tagged markers were employed in association mapping to detect quantitative trait loci（QTL） responsible for these variations. Among the 7 subpopulations, POP5 in japonica group showed the largest values of HD and grain width（GW）, but the smallest values of grain length（GL） and grain length to width ratio（GLW）. Among the six indica groups, POP7 had the largest values of HD, GL, GLW, and 1 000-grain weight（TGW）. A total of 27 QTLs were detected underlying these phenotypic variations in single year, while 12 of them could be detected in 2006 and 2007. GS3 marker was closely associated with GL, GW and GLW, and widely distributed in different groups. The starch synthesis related gene markers, SSI, SSIIa, SBE1, AGPL4, and ISA1, were linked to plant height（PH）, panicle length（PL）, flag leaf length（FLL）, GW, and GLW. The SSR markers, RM267, RM340 and RM346, were linked to at least two traits. Therefore, these new markers will probably be used to improve rice grain yield or plant architecture when performing marker-assisted selection of proper alleles.
