Soybean transformation by ovary-drip was improved by optimizing the length of the transformation pathway by cutting the styles. These modifications facilitated soybean transformation manipulation and improved transfor...Soybean transformation by ovary-drip was improved by optimizing the length of the transformation pathway by cutting the styles. These modifications facilitated soybean transformation manipulation and improved transformation reproducibility and efficiency. Using a linear minimal gus gene cassette as the foreign DNA, a maximum transformation frequency of 11% was obtained in flowers of the soybean cultivar ‘Liaodou 14’ with their styles mostly removed, whereas removal of only the stigma, partial style cutting and partial ovary cutting gave transformation frequencies of 0%, 1%, and 2%, respectively. An average transformation frequency of 8.2% was obtained when 619 flowers from three soybean cultivars (‘Liaodou 14’, ‘Liaodou 13’, and ‘Tiefeng 29’) were transformed by this optimized method. Southern blotting analysis showed that the gus reporter gene (encoding β-glucuronidase) was stably inherited with a simple pattern. Reverse transcription-polymerase chain reaction (RT-PCR) and GUS staining confirmed the expression of the gus gene in transgenic plants.展开更多
The conventional processes for recovery of silver from cyanide leach solutions are the carbon adsorption, the Merrill-Crowe zinc dust cementation, the Ion Exchange, and Solvent Extraction processes;among other availab...The conventional processes for recovery of silver from cyanide leach solutions are the carbon adsorption, the Merrill-Crowe zinc dust cementation, the Ion Exchange, and Solvent Extraction processes;among other available options for recovery of precious metals from cyanide solutions, Electrocoagulation (EC) is a very promising electrochemical process that does not require high concentrations of silver in cyanide solutions to yield excellent results and neither pretreatment of cyanide solutions like Merrill-Crowe process (deoxygenating and clarification). The present study has been done for the recovery of silver contained in pregnant solution from the cyanidation process using the electrocoagulation technology with iron electrodes, and therefore develops an alternative technology for Merril-Crowe process. The average silver content in pregnant solution was of 52 ppm, recovery was obtained of 99% of silver, with this optimum operating parameters, pH = 8, residence time = 20 minutes and conductivity by addition of sodium chloride = 4 grs/L. Finally the characterization of the solid products formed during the EC process with X-ray Diffraction and Scanning Electronic Microscope was performed, results suggest that magnetite particles and amorphous iron oxyhydroxides are present (Lepidocrocite).展开更多
Abstract: Seven hundred and fourteen individuals of the Scilla sinensis (Louriro) Merrill complex were sampled from 21 populations at 19 localities in 10 provinces and two cities of China and investigated cytologicall...Abstract: Seven hundred and fourteen individuals of the Scilla sinensis (Louriro) Merrill complex were sampled from 21 populations at 19 localities in 10 provinces and two cities of China and investigated cytologically in order to test its cytotype composition and cytogeographical variation still further. Five cytotypes were found (i.e. AA (2n = 16), BB (2n = 18), AABB (2n = 34), AAA (2n = 24), and AABB+9 (2n = 43)). Until now, nine of the 12 cytotypes have been identified on the continent, which indicates that it is an important place for the cytotypic differentiation of the complex. The cytotype AABB+9 is a new record on the continent. AAA was recorded for the second time in this complex. The majority of populations are composed of only one cytotype (AA, BB, or AABB), whereas another four populations consist of more than two cytotypes involving AA, BB, AAA, AABB, and AABB+9. The distribution of BB covers the entire region south to Huai River, whereas AA populations are distributed in Taiwan, Fujian, Hong Kong, and Guangdong and are isolated from its major distribution. The appearance of AABB+9 is possibly evidence for the degeneration of the subglobular bulb type of AABB and the fact that AAA and AAAA exist in the interior border regions of the range of this complex probably suggests that drought is a major factor promoting plant polyploidization. In addition, the mean numbers of B chromosomes per individual, the percentage of individuals with the B chromosome in each population, and the correlation coefficients between the latter and their latitude/longitude were calculated. Generally speaking, the B chromosome number is higher in BB populations compared with AA populations and there is a prominent tendency that the B chromosome content in either AA or BB populations correlates with the latitude and longitude of the populations.展开更多
The improvement of soybean seed carotenoid contents is very important due to the beneficial role of carotenoids in human health and nutrition. However, the genetic architecture underlying soybean carotenoid biosynthes...The improvement of soybean seed carotenoid contents is very important due to the beneficial role of carotenoids in human health and nutrition. However, the genetic architecture underlying soybean carotenoid biosynthesis remains largely unknown. In the present study, we employed next generation sequencing-based bulked-segregant analysis to identify new genomic regions governing seed carotenoids in 1,551 natural soybean accessions. The genomic DNA samples of individual plants with extreme phenotypes were pooled to form two bulks with high(50 accessions) and low(50 accessions) carotenoid contents for Illumina sequencing. A total of 125.09 Gb of clean bases and 89.82% of Q30 were obtained, and the average alignment efficiency was 99.45% with an average coverage depth of 62.20× and 99.75% genome coverage. Based on the G prime statistic algorithm(G') method analysis, 16 candidate genomic loci with a total length 20.41 Mb were found to be related to the trait. Of these loci, the most significant regions displaying the highest elevated G' values were found in chromosome 06 at a position of 18.53–22.67 Mb, and chromosome 19 at genomic region intervals of 8.36–10.94, 12.06–13.79 and 18.45–20.26 Mb. These regions were then used to identify the key candidate genes. In these regions, 250 predicted genes were found and analyzed to obtain 90 significantly enriched(P<0.05) Gene Ontology(GO) terms. Based on ANNOVAR analysis, 50 genes with non-synonymous and stopgained mutations were preferentially selected as potential candidate genes. Of those 50 genes, following their gene annotation functions and high significant haplotype variations in various environments,five genes were identified as the most promising candidate genes regulating soybean seed carotenoid accumulation, and they should be investigated in further functional validation studies. Collectively, understanding the genetic basis of carotenoid pigments and identifying genes underpinning carotenoid accumulation via a bulked-segregant analysis-based sequencing(BSA-seq) approach provide new insights for exploring future molecular breeding efforts to produce soybean cultivars with high carotenoid content.展开更多
基金Project (No. JY03-B-18-02) supported by the National R & D Project of Transgenic Crops of Ministry of Science and Technology of China
文摘Soybean transformation by ovary-drip was improved by optimizing the length of the transformation pathway by cutting the styles. These modifications facilitated soybean transformation manipulation and improved transformation reproducibility and efficiency. Using a linear minimal gus gene cassette as the foreign DNA, a maximum transformation frequency of 11% was obtained in flowers of the soybean cultivar ‘Liaodou 14’ with their styles mostly removed, whereas removal of only the stigma, partial style cutting and partial ovary cutting gave transformation frequencies of 0%, 1%, and 2%, respectively. An average transformation frequency of 8.2% was obtained when 619 flowers from three soybean cultivars (‘Liaodou 14’, ‘Liaodou 13’, and ‘Tiefeng 29’) were transformed by this optimized method. Southern blotting analysis showed that the gus reporter gene (encoding β-glucuronidase) was stably inherited with a simple pattern. Reverse transcription-polymerase chain reaction (RT-PCR) and GUS staining confirmed the expression of the gus gene in transgenic plants.
文摘The conventional processes for recovery of silver from cyanide leach solutions are the carbon adsorption, the Merrill-Crowe zinc dust cementation, the Ion Exchange, and Solvent Extraction processes;among other available options for recovery of precious metals from cyanide solutions, Electrocoagulation (EC) is a very promising electrochemical process that does not require high concentrations of silver in cyanide solutions to yield excellent results and neither pretreatment of cyanide solutions like Merrill-Crowe process (deoxygenating and clarification). The present study has been done for the recovery of silver contained in pregnant solution from the cyanidation process using the electrocoagulation technology with iron electrodes, and therefore develops an alternative technology for Merril-Crowe process. The average silver content in pregnant solution was of 52 ppm, recovery was obtained of 99% of silver, with this optimum operating parameters, pH = 8, residence time = 20 minutes and conductivity by addition of sodium chloride = 4 grs/L. Finally the characterization of the solid products formed during the EC process with X-ray Diffraction and Scanning Electronic Microscope was performed, results suggest that magnetite particles and amorphous iron oxyhydroxides are present (Lepidocrocite).
文摘Abstract: Seven hundred and fourteen individuals of the Scilla sinensis (Louriro) Merrill complex were sampled from 21 populations at 19 localities in 10 provinces and two cities of China and investigated cytologically in order to test its cytotype composition and cytogeographical variation still further. Five cytotypes were found (i.e. AA (2n = 16), BB (2n = 18), AABB (2n = 34), AAA (2n = 24), and AABB+9 (2n = 43)). Until now, nine of the 12 cytotypes have been identified on the continent, which indicates that it is an important place for the cytotypic differentiation of the complex. The cytotype AABB+9 is a new record on the continent. AAA was recorded for the second time in this complex. The majority of populations are composed of only one cytotype (AA, BB, or AABB), whereas another four populations consist of more than two cytotypes involving AA, BB, AAA, AABB, and AABB+9. The distribution of BB covers the entire region south to Huai River, whereas AA populations are distributed in Taiwan, Fujian, Hong Kong, and Guangdong and are isolated from its major distribution. The appearance of AABB+9 is possibly evidence for the degeneration of the subglobular bulb type of AABB and the fact that AAA and AAAA exist in the interior border regions of the range of this complex probably suggests that drought is a major factor promoting plant polyploidization. In addition, the mean numbers of B chromosomes per individual, the percentage of individuals with the B chromosome in each population, and the correlation coefficients between the latter and their latitude/longitude were calculated. Generally speaking, the B chromosome number is higher in BB populations compared with AA populations and there is a prominent tendency that the B chromosome content in either AA or BB populations correlates with the latitude and longitude of the populations.
基金financially supported by the National Natural Science Foundation of China (32161143033, 32272178, and 32001574)National Key Research and Development Program of China (2021YFD1201605)the Agricultural Science and Technology Innovation Project of CAAS。
文摘The improvement of soybean seed carotenoid contents is very important due to the beneficial role of carotenoids in human health and nutrition. However, the genetic architecture underlying soybean carotenoid biosynthesis remains largely unknown. In the present study, we employed next generation sequencing-based bulked-segregant analysis to identify new genomic regions governing seed carotenoids in 1,551 natural soybean accessions. The genomic DNA samples of individual plants with extreme phenotypes were pooled to form two bulks with high(50 accessions) and low(50 accessions) carotenoid contents for Illumina sequencing. A total of 125.09 Gb of clean bases and 89.82% of Q30 were obtained, and the average alignment efficiency was 99.45% with an average coverage depth of 62.20× and 99.75% genome coverage. Based on the G prime statistic algorithm(G') method analysis, 16 candidate genomic loci with a total length 20.41 Mb were found to be related to the trait. Of these loci, the most significant regions displaying the highest elevated G' values were found in chromosome 06 at a position of 18.53–22.67 Mb, and chromosome 19 at genomic region intervals of 8.36–10.94, 12.06–13.79 and 18.45–20.26 Mb. These regions were then used to identify the key candidate genes. In these regions, 250 predicted genes were found and analyzed to obtain 90 significantly enriched(P<0.05) Gene Ontology(GO) terms. Based on ANNOVAR analysis, 50 genes with non-synonymous and stopgained mutations were preferentially selected as potential candidate genes. Of those 50 genes, following their gene annotation functions and high significant haplotype variations in various environments,five genes were identified as the most promising candidate genes regulating soybean seed carotenoid accumulation, and they should be investigated in further functional validation studies. Collectively, understanding the genetic basis of carotenoid pigments and identifying genes underpinning carotenoid accumulation via a bulked-segregant analysis-based sequencing(BSA-seq) approach provide new insights for exploring future molecular breeding efforts to produce soybean cultivars with high carotenoid content.
