The rich genetic variation preserved in collections of Aegilops tauschii can be readily exploited to improve common wheat using synthetic hexaploid wheat lines. However,hybrid necrosis, which is characterized by progr...The rich genetic variation preserved in collections of Aegilops tauschii can be readily exploited to improve common wheat using synthetic hexaploid wheat lines. However,hybrid necrosis, which is characterized by progressive death of leaves or plants, has been observed in certain interspecific crosses between tetraploid wheat and Ae. tauschii. The aim of this study was to construct a fine genetic map of a gene(temporarily named Net Jing Y176)conferring hybrid necrosis in Ae. tauschii accession Jing Y176. A triploid F1 population derived from distant hybridization between Ae. tauschii and tetraploid wheat was used to map the gene with microsatellite markers. The newly developed markers Xsdau K539 and Xsdau K561 co-segregated with Net Jing Y176 on chromosome arm 2DS. The tightly linked markers developed in this study were used to genotype 91 Ae. tauschii accessions. The marker genotype analysis suggested that 49.45% of the Ae. tauschii accessions carry Net Jing Y176. Interestingly, hybrid necrosis genotypes tended to appear more commonly in Ae. tauschii ssp. tauschii than in Ae. tauschii ssp. strangulata.展开更多
The full-length of intact Zea mays gene for phosphoenolpyruvate carboxylase gene （ZmC4Ppc） is 6 781 bp. The products of PCR for this gene were not clear with poor repeatability, resulting in that it was difficult fo...The full-length of intact Zea mays gene for phosphoenolpyruvate carboxylase gene （ZmC4Ppc） is 6 781 bp. The products of PCR for this gene were not clear with poor repeatability, resulting in that it was difficult for marker-assisted selection （MAS） both in rice and maize. For selecting the markers for MAS, sequences presented only in maize rather than in rice were identified by BLAST, and used for primer design using Primer Premier 5.0. A pair of specific primer termed MRpc （Forward： 5＇ AAGCAGGGAAGCGAGACG 3＇, Reverse： 5＇ GATTGCCGCCAGCAGTAG 3＇） was used for selection of transformed rice, and ZmC4Ppc could be highly and constitutively expressed at each tested developmental stages in the transformed rice selected by using MRpc. Thus, MRpc was used for MAS of progenies carrying ZmC4Ppc gene in rice and some restorer lines with ZmC4Ppc （e.g. FPM881） derived from ZmC4Ppc-transformed Kitaake backcrossed with a restorer line Shuhui 881 were obtained. The analyses on genetic background, PEPCase activity, net photosynthetic rate, general combining ability （GCA） and specific combining ability （SCA） of FPM881 showed that similarity of genetic background reached above 95%, the PEPCase and net photosynthetic rate were higher than those of the control, and some of the progenies carrying ZmC4Ppc gene had better GCA and SCA for grain yield per plant, number of panicles per plant, and 1000-grain weight than those of the control. This suggested that the introduction of maize ZmC4Ppc gene via MAS and its stable expression could increase grain yield of rice and would likely provide a pathway for rice varietal improvement.展开更多
The spatial-temporal measurement of complex wave evolution is significant in studying wave-structure interactions.Current methods,such as that using wave probes,have shown limitations in measuring the wave evolution a...The spatial-temporal measurement of complex wave evolution is significant in studying wave-structure interactions.Current methods,such as that using wave probes,have shown limitations in measuring the wave evolution around structures in laboratories.In this study,an improved stereo imaging method is proposed for measuring the wave evolution around a fixed structure.Regular wave tests were conducted on a fixed surface-piercing square column in a wave flume to validate the reliability and accuracy of the proposed method.A flexible markernet made of foam particles was arranged around the column to pro-vide Lambertian features for the water surface.Two synchronized stereo imaging systems covered all the surrounding areas of the column and provided stereo pair sequences for wave evolution.Subsequently,image segmentation techniques were used to mask the low-confidence disparities in stereo matching,and finally,three-dimensional(3D)wave surfaces were reconstructed in the time sequence.The time histories of the wave elevations at particular locations were extracted and agreed well with the measurements of wave probes with an average bias of 2.4%.Subsequently,the reconstructed 3D wave field was sliced,exhibiting the instantaneous profiles that agreed with the measurements of wave probes.Moreover,the wave run-up height ratios were consistent with those of a previous study,thereby verifying the method’s accuracy from the perspective of spatial evolution.The results demonstrated that the proposed method was capable of precisely measuring the spatial-temporal evolution of the wave field around the square column and displayed potential for application in more studies on wave-structure interactions.展开更多
基金financially supported by the National Natural Science Foundation of China (grant numbers 31171553 and 31471488)the National Basic Research Program of China (2014CB138100)+2 种基金the National High Technology Research and Development Program of China (2011AA100102 and 2012AA101105)Shandong Seed Engineering Project (2015–2019)the Program of Introducing International Super Agricultural Science and Technology (948 program, 2013-S19)
文摘The rich genetic variation preserved in collections of Aegilops tauschii can be readily exploited to improve common wheat using synthetic hexaploid wheat lines. However,hybrid necrosis, which is characterized by progressive death of leaves or plants, has been observed in certain interspecific crosses between tetraploid wheat and Ae. tauschii. The aim of this study was to construct a fine genetic map of a gene(temporarily named Net Jing Y176)conferring hybrid necrosis in Ae. tauschii accession Jing Y176. A triploid F1 population derived from distant hybridization between Ae. tauschii and tetraploid wheat was used to map the gene with microsatellite markers. The newly developed markers Xsdau K539 and Xsdau K561 co-segregated with Net Jing Y176 on chromosome arm 2DS. The tightly linked markers developed in this study were used to genotype 91 Ae. tauschii accessions. The marker genotype analysis suggested that 49.45% of the Ae. tauschii accessions carry Net Jing Y176. Interestingly, hybrid necrosis genotypes tended to appear more commonly in Ae. tauschii ssp. tauschii than in Ae. tauschii ssp. strangulata.
文摘The full-length of intact Zea mays gene for phosphoenolpyruvate carboxylase gene （ZmC4Ppc） is 6 781 bp. The products of PCR for this gene were not clear with poor repeatability, resulting in that it was difficult for marker-assisted selection （MAS） both in rice and maize. For selecting the markers for MAS, sequences presented only in maize rather than in rice were identified by BLAST, and used for primer design using Primer Premier 5.0. A pair of specific primer termed MRpc （Forward： 5＇ AAGCAGGGAAGCGAGACG 3＇, Reverse： 5＇ GATTGCCGCCAGCAGTAG 3＇） was used for selection of transformed rice, and ZmC4Ppc could be highly and constitutively expressed at each tested developmental stages in the transformed rice selected by using MRpc. Thus, MRpc was used for MAS of progenies carrying ZmC4Ppc gene in rice and some restorer lines with ZmC4Ppc （e.g. FPM881） derived from ZmC4Ppc-transformed Kitaake backcrossed with a restorer line Shuhui 881 were obtained. The analyses on genetic background, PEPCase activity, net photosynthetic rate, general combining ability （GCA） and specific combining ability （SCA） of FPM881 showed that similarity of genetic background reached above 95%, the PEPCase and net photosynthetic rate were higher than those of the control, and some of the progenies carrying ZmC4Ppc gene had better GCA and SCA for grain yield per plant, number of panicles per plant, and 1000-grain weight than those of the control. This suggested that the introduction of maize ZmC4Ppc gene via MAS and its stable expression could increase grain yield of rice and would likely provide a pathway for rice varietal improvement.
基金the support of the National Natural Science Foundation of China(Grant Nos.52031006 and 42206192)Shanghai Sailing Program,China(Grant No.20YF1419800).
文摘The spatial-temporal measurement of complex wave evolution is significant in studying wave-structure interactions.Current methods,such as that using wave probes,have shown limitations in measuring the wave evolution around structures in laboratories.In this study,an improved stereo imaging method is proposed for measuring the wave evolution around a fixed structure.Regular wave tests were conducted on a fixed surface-piercing square column in a wave flume to validate the reliability and accuracy of the proposed method.A flexible markernet made of foam particles was arranged around the column to pro-vide Lambertian features for the water surface.Two synchronized stereo imaging systems covered all the surrounding areas of the column and provided stereo pair sequences for wave evolution.Subsequently,image segmentation techniques were used to mask the low-confidence disparities in stereo matching,and finally,three-dimensional(3D)wave surfaces were reconstructed in the time sequence.The time histories of the wave elevations at particular locations were extracted and agreed well with the measurements of wave probes with an average bias of 2.4%.Subsequently,the reconstructed 3D wave field was sliced,exhibiting the instantaneous profiles that agreed with the measurements of wave probes.Moreover,the wave run-up height ratios were consistent with those of a previous study,thereby verifying the method’s accuracy from the perspective of spatial evolution.The results demonstrated that the proposed method was capable of precisely measuring the spatial-temporal evolution of the wave field around the square column and displayed potential for application in more studies on wave-structure interactions.
