Anthracnose,caused by Colletotrichum truncatum and C.gloeosporioides,is amongst the most serious diseases of soybean in China.Picoxystrobin,a quinone outside inhibitor fungicide,is commonly used for the control of ant...Anthracnose,caused by Colletotrichum truncatum and C.gloeosporioides,is amongst the most serious diseases of soybean in China.Picoxystrobin,a quinone outside inhibitor fungicide,is commonly used for the control of anthracnose.Its resistance risk and mechanism in C.truncatum and C.gloeosporioides are unclear.In this study,the sensitivities of 128 C.truncatum and 121 C.gloeosporioides isolates to picoxystrobin were investigated,and unimodal distributions were observed with average EC_(50)values of 0.7740 and 1.1561μg mL^(-1),respectively.Eleven picoxystrobin-resistant mutants of C.truncatum and six mutants of C.gloeosporioides were acquired,with EC_(50)values varying from 5.40-152.96 and 13.53-28.30μg mL^(-1),respectively.Compared to the parental isolates,mutants showed similar or higher relative fitness in conidial production and germination,and pathogenicity.Collectively,the resistance risk of C.truncatum and C.gloeosporioides to picoxystrobin is moderate to high.There was positive cross-resistance between picoxystrobin and pyraclostrobin,but not between picoxystrobin and fluazinam,difenoconazole,or propiconazole.The G143S mutation in Cyt b protein was detected in seven high-resistant mutants of C.truncatum(RF>100),and G137R occurred in four moderate-resistant mutants(RF<_(50)).Contrastingly,there were no point mutations in Cyt b of any C.gloeosporioides mutants.Molecular docking confirmed that two mutations conferred different resistance levels to picoxystrobin.Under greenhouse trials,picoxystrobin did not control mutants with the G143S mutation,those bearing G137R or no point mutation were somewhat controlled,but at a lower level compared to wild-type isolates.These results showed that integrated management strategies should be implemented to preserve fungicide effectiveness.展开更多
Nervonic acid is the world’s first and only potent substance that can repair damaged nerve fibers and promote nerve cell regeneration with high nutritional value.The wide variety of fatty acids in plant oils and fats...Nervonic acid is the world’s first and only potent substance that can repair damaged nerve fibers and promote nerve cell regeneration with high nutritional value.The wide variety of fatty acids in plant oils and fats with similar structures makes the large-scale separation and purification of high-purity nervonic acid very difficult.A new combined process of molecular distillation,urea inclusion and solvent crystallization was established to prepare high-purity nervonic acid with the mixed fatty acids obtained after saponification and acidification of Acer truncatum Bunge oil as raw materials.First,according to the difference in the mean free path of fatty acids,molecular distillation was used to separate and remove C16 saturated fatty acid of palmitic acid and four C18-C20 fatty acids of stearic,oleic,linoleic,and linolenic acids.The content of C16-C20 fatty acids decreased from 72.92% to 19.22% after two-stage molecular distillation processes,in which the contents of saturated fatty acid of palmitic acid decreased to about 0.5%.Then,according to the difference in carbon chain length and saturation of fatty acid,the contents of C22-C24 saturated fatty acids of tetracosanoic and docosanoic acids decreased to 0.21% and 0.07% by urea inclusion with urea/free fatty acid preparation by saponification(SPOMFs)ratio as 0.6.In addition,all saturated fatty acids were basically separated.Finally,according to the difference in the solubility of fatty acids in solvents,the C18-C20 unsaturated fatty acids of oleic,linoleic,and linolenic acids and C22 unsaturated fatty acid of erucic acid were removed by solvent crystallization.The content of C18-C20 unsaturated fatty acids decreased to less than 5% with pentanol as the solvent after the first stage solvent crystallization.The content of erucic acid decreased to 3.47% with anhydrous ethanol as the solvent after the second to fifth stage solvent crystallization.The combined process of molecular distillation,urea inclusion and low temperature crystallization innovatively adopted an efficient,simple and easy-toindustrial solvent crystallization method to separate erucic and nervonic acids,obtaining nervonic acid with purity of 96.53% and final yield of 47.99%.展开更多
The literature highlights that a severe infection by the fungus Colletotrichum truncatum may be capable of inflicting considerable damage to seeds after harvest, potentially affecting their chemical composition and ph...The literature highlights that a severe infection by the fungus Colletotrichum truncatum may be capable of inflicting considerable damage to seeds after harvest, potentially affecting their chemical composition and physiological quality. Taking into account that currently there is no categorization in terms of susceptibility and tolerance on this pathogen, the present work is presented with the main objective of “Evaluate the influence of Pathogenicity of C. truncatum on the physiological quality (germination, vigor, viability) and biochemical components in different varieties of soybean seeds (Glycine max)” most planted in the region. The work was carried out in the Agrotec laboratory, located in the Municipality of San Alberto (Alto Paraná), using a completely randomized experimental design, with AxB factorial arrangement, where A indicates ten most planted soybean varieties in the region and B with or without artificial inoculation of Colletotrichum truncatum, with twenty treatments and four repetitions. The variables evaluated were: germination, vigor, viability and chemical composition. The data were subjected to analysis of variance and the Tukey test at 5% error. The results showed a significant statistical difference, accepting the alternative hypothesis proposed “The pathogenicity of Colletotrichum truncatum influences the physiological quality (germination, vigor, viability) and biochemical components (saturated and unsaturated fatty acids) in different varieties of soybean seeds (Glycine max)”.展开更多
[Objective] Cloning of the AtrMYB transcription factor gene from Acer truncatum was conducted to further explore the red leaf development mechanism and breed cultivars of colored-leaf maple. [Method] The Acer truncat...[Objective] Cloning of the AtrMYB transcription factor gene from Acer truncatum was conducted to further explore the red leaf development mechanism and breed cultivars of colored-leaf maple. [Method] The Acer truncatum ‘Luhong No.1' cultivar was used as the material for cloning the MYB gene by mean of RTPCR and RACE-PCR. [Results] Sequence analysis showed that the fragment contained a full coding region of 831 bp encoding 276 amino acid residues with a molecular weight of 32.17 kD and a molecular formula C_(1430)H_(14052)N_(2247)O_(406)S_(14). The gene was named as AtrMYB with a Gen Bank accession number of 1825712. This coded protein had apI of 9.44. The results showed that the AtrMYB exhibited typical features of the R2R3-MYB domain. The AtrMYB was highly homologous with the MYB of other species at nucleotide and amino acid levels. The AtrMYB had no signal peptide, but a nuclear localization signal. The phylogenetic tree showed that the AtrMYB was at the same clade as the MYB from Citrus sinensis. [Conclusion] The AtrMYB was cloned from Acer truncatum ‘Luhong No.1' cultivar. These results have provided a foundation for further purification and identification of target protein and function study of the AtrMYB.展开更多
[Objective] This study aimed to clone and analyze the sequence of CHS gene from Acer truncatum leaves. [Method] Using A. truncatum cultivars No.1-6 as experimental materials, total RNA was extracted from A. truncatum ...[Objective] This study aimed to clone and analyze the sequence of CHS gene from Acer truncatum leaves. [Method] Using A. truncatum cultivars No.1-6 as experimental materials, total RNA was extracted from A. truncatum leaves with the modified CTAB method. CHS gene sequences were downloaded from the NCBI and aligned by BLAST. Degenerate primers were designed by DNAMAN and Primer- premier5 to amplify the target band. CHS gene fragment was amplified by RT-PCR and ligated to pMD18-T vector. The identified positive colonies were sequenced. [Result] A 1 365 bp fragment was amplified. Sequence analysis suggested that the obtained fragment encoded 365 amino acids and shared above 90% homology to nucleotide sequence of CHS gene from A. palmatum and A. [Conclusion] In this study, CHS gene was successfully cloned from A. truncatum for the first time, which laid the foundation for efficient utilization of CHS gene.展开更多
Plant volatile organic compounds (Biogenic Volatile Organic compounds, referred BVOCs) have a significant impact on the atmospheric environment, air quality and human health. This experiment takes Acer truncatum flowe...Plant volatile organic compounds (Biogenic Volatile Organic compounds, referred BVOCs) have a significant impact on the atmospheric environment, air quality and human health. This experiment takes Acer truncatum flowers as the research object, uses solid-phase micro-extraction combine GC-MS (SPME-GC-MS) to detect the main component of volatiles released by the flowers from 10 individual trees of Acer truncatum (Acer truncatum Bunge). The results showed that 37 kinds of volatiles were detected and they are belonged to four types organic compouds, such as terpenoids, alcohols, ketones, esters. According to the analysis of the main components of Acer truncatum flower volatiles includes Fluorene, 4,8 -Dimethyl-1,3 (E), 7-Nonene, (cis, trans)-2,6-Dimethyl-2,4,6-triene-Partenkirchen, Myrcene, Basil hexene, 3-Carene, (E)-Basil, Camphene, Caryophyllene, Linalool, α-Terpinolene, O-cymene, 3-Vinyl-1,2-dimethyl-1, Eucalyptus alcohols and Alcohol vinegar-12. However, there were no significant differences between individual trees in terms of obscure material O-cymene, Eucalyptus alcohols, Alcohol vinegar-12, as well as the significant differences in terms of remaining volatiles.展开更多
The use of microbes and microbial products as bioherbicides has been studied for several decades, and combinations of bioherbicides and herbicides have been examined to discover possible synergistic interactions to im...The use of microbes and microbial products as bioherbicides has been studied for several decades, and combinations of bioherbicides and herbicides have been examined to discover possible synergistic interactions to improve weed control efficacy. Bioassays were conducted to assess possible interactions of the herbicide glufosinate [2-amino-4-(hydroxymethylphosphinyl) butanoic acid] and Colletotrichum truncatum (CT), a fungal bioherbicide to control hemp sesbania (Sesbania exaltata)]. Glufosinate acts as a glutamine synthetase (GS) inhibitor that causes elevated ammonia levels, but the mode of action of CT is unknown. GS has also been implicated in plant defense in certain plant-pathogen interactions. The effects of spray applications of glufosinate (1.0 mM) orbioherbicide (8.0 × 104 conidia ml-1), applied alone or in combination were monitored (88 h time-course) on seedling growth, GS activity and ammonia levels in hypocotyl tissues under controlled environmental conditions. Growth (elongation and fresh weight) and extractable GS activity were inhibited in tissues by glufosinate and glufosinate plus CT treatments as early as 16 h, but CT treatment did not cause substantial growth reduction or GS inhibition until after ~40 h. Generally, ammonia levels in hemp sesbania tissues under these various treatments were inversely correlated with GS activity. Localization of hemp sesbania GS activity on electrophoretic gels indicated a lack of activity after 30 h in glufosinate and glufosinate plus CT-treated tissue. Untreated control tissues contained much lower ammonia levels at 24, 64, and 88 h after treatment than treatments with CT, glufosinate or their combination. CT alone caused elevated ammonia levels only after 64 - 88 h. Glufosinate incorporated in agar at 0.25 mM to 2.0 mM, caused a 10% - 45% reduction of CT colony radial growth, compared to fungal growth on agar without glufosinate, and the herbicide also inhibited sporulation of CT. Although no synergistic interactions were found in the combinations of CT and glufosinate at the concentrations used, further insight on the biochemical action of CT and its interactions with this herbicide on hemp sesbania was achieved.展开更多
[ Objective] This study aimed to establish DNA fingerprints of 23 Acer truncatum clones, thus providing the theoretical basis for selection, classification and identification of A. truncatum varieties. [Metho...[ Objective] This study aimed to establish DNA fingerprints of 23 Acer truncatum clones, thus providing the theoretical basis for selection, classification and identification of A. truncatum varieties. [Method] Sixteen pairs of SRAP primers with rich polymorphism and high specificity were used to establish DNA fin-gerprints. [Result] A total of 223 bands were amplified with 16 primer pairs, including 197 polymorphic bands. Averagely 13.9 loci and 12.3 polymorphic loci were amplified with each primer pair. The average percentage of polymorphic loci reached 88. 34% . [ Conclusion] The classification result drawn by cluster analy-sis is consistent with that obtained based on main characteristics and genetic relationships of A. truncatum, clones. By using DNA fingerprints established with prim-er pairs ME1-EM4 and ME2-EM1, 23 A. truncatum clones can be effectively distinguished, and the confidence probability is greater than 99.99%.展开更多
Colletotrichum truncatum, grown on rice grain (3 to 4 weeks, 22°C to 24°C) produced a fungus-infested rice mixture of microsclerotia and conidia (spores) in a ratio of ~9:1, respectively. Greenhouse tests of...Colletotrichum truncatum, grown on rice grain (3 to 4 weeks, 22°C to 24°C) produced a fungus-infested rice mixture of microsclerotia and conidia (spores) in a ratio of ~9:1, respectively. Greenhouse tests of this formulation (0.4 to 50 mg finely-ground fungus-rice product) which applied pre-emergence to 5 cm2 of soil surface, caused 22% to 96% hemp sesbania plant mortality, after 14 days. Post-emergence treatment (fungus-rice aqueous formulation;2.4 × 105 microsclerotia ml-1, 30% unrefined corn oil and 0.2% Silwet L-77 surfactant) of weeds surviving the pre-emergence application, resulted in 93% mortality, after 14 days. Based on greenhouse results, field tests were undertaken: 1) pre-emergence treatment (fungus-rice formulation at 2.4 × 105 microsclerotia cm-2), 2) post-emergence (fungus-rice product in 30% unrefined corn oil, 0.2% Silwet) only treatment, applied 15 days after planting and 3) pre-emergence treatment followed by post-emergence treatment (fungus-rice product in 30% unrefined corn oil, 0.2% Silwet) applied 15 days after planting to surviving weeds. Control treatments were: 1) autoclaved rice product sans fungus, 2) unrefined corn oil (30% unrefined corn oil, 0.2% Silwet in water) and 3) untreated plants. Planting dates were: early season (April-May), early-mid season (June-July), late-mid season (July-August), and late season (September-October). Weed mortality was recorded at 15 days for the pre-plus post-treatment, and at 30 days after planting for the pre-emergence only and the post-treatment only. The early season, pre-emergence treatment caused 67% hemp sesbania mortality (3-yr average) within 15 days and the post-emergence treatment caused 91% mortality of the surviving weeds. In the late-mid-season, pre-emergence treatment caused minimal (<5%) mortality at 15 days, but mortality in the post-emergence treatment was >80%. Results suggest that seasonal environmental conditions are important in the efficacy of this C. truncatum-rice product formulation when applied pre- or post-emergence to this onerous weed.展开更多
Leaves of Acer truncatum ' Luhong No. 1 ' contain large amounts of polysaccharides and polyphenols, which seriously affect extraction yield and quality of total RNA. In order to explore the appropriate total RNA ext...Leaves of Acer truncatum ' Luhong No. 1 ' contain large amounts of polysaccharides and polyphenols, which seriously affect extraction yield and quality of total RNA. In order to explore the appropriate total RNA extraction method, total RNA was extracted from leaves of A. truncatum ' Luhong No. 1 ' with three methods, including kit method, Trizol method and modified CTAB method. The results showed that ODE6o/OD2so and OD^o/OD2ao ratios of total RNA extracted from leaves of A. truncatum ' Luhong No. 1 ' with kit method were higher than 1.8, with a general yield and certain level of DNA contamination ; OD^o/OD~ and OD^o/OD^o ratios of total RNA extracted with Trizol method were about 1.5, with the lowest yield; OD260/OD280 and OD260/OD230 ratios of total RNA extracted with modified CTAB method were about 2.0, with the highest yield and distinct eleetrophoresis patterns. The results demonstrated that total RNA extracted with modified CTAB method exhibited high yield and purity, which could meet the demands of subsequent molecular biology research. Thus, modified CTAB method is the appro- oriate method for extracting total RNA from leaves of A. truncatum ' Luhong No. 1 '展开更多
基金funded by the Natural Science Foundation of Fujian Province, China (2021J01476)East and West Cooperation Project of the Fujian Academy of Agricultural Sciences, China (DKBF2022-01)+2 种基金the Project of Department of Agriculture and Rural Affairs in Fujian Province (2021PZQS006)the “5511” Collaborative Innovation Project of High-quality Agricultural Development and Surpassment in Fujian Province (XTCXGC2021011)the Team Project Funding of Scientific Research Innovation of FAAS, China (CXTD2021002-1).
文摘Anthracnose,caused by Colletotrichum truncatum and C.gloeosporioides,is amongst the most serious diseases of soybean in China.Picoxystrobin,a quinone outside inhibitor fungicide,is commonly used for the control of anthracnose.Its resistance risk and mechanism in C.truncatum and C.gloeosporioides are unclear.In this study,the sensitivities of 128 C.truncatum and 121 C.gloeosporioides isolates to picoxystrobin were investigated,and unimodal distributions were observed with average EC_(50)values of 0.7740 and 1.1561μg mL^(-1),respectively.Eleven picoxystrobin-resistant mutants of C.truncatum and six mutants of C.gloeosporioides were acquired,with EC_(50)values varying from 5.40-152.96 and 13.53-28.30μg mL^(-1),respectively.Compared to the parental isolates,mutants showed similar or higher relative fitness in conidial production and germination,and pathogenicity.Collectively,the resistance risk of C.truncatum and C.gloeosporioides to picoxystrobin is moderate to high.There was positive cross-resistance between picoxystrobin and pyraclostrobin,but not between picoxystrobin and fluazinam,difenoconazole,or propiconazole.The G143S mutation in Cyt b protein was detected in seven high-resistant mutants of C.truncatum(RF>100),and G137R occurred in four moderate-resistant mutants(RF<_(50)).Contrastingly,there were no point mutations in Cyt b of any C.gloeosporioides mutants.Molecular docking confirmed that two mutations conferred different resistance levels to picoxystrobin.Under greenhouse trials,picoxystrobin did not control mutants with the G143S mutation,those bearing G137R or no point mutation were somewhat controlled,but at a lower level compared to wild-type isolates.These results showed that integrated management strategies should be implemented to preserve fungicide effectiveness.
基金supported by the National Natural Science Foundation of China(22125802 and 22078010)Beijing Natural Science Foundation(2222017)Big Science Project from BUCT(XK180301).
文摘Nervonic acid is the world’s first and only potent substance that can repair damaged nerve fibers and promote nerve cell regeneration with high nutritional value.The wide variety of fatty acids in plant oils and fats with similar structures makes the large-scale separation and purification of high-purity nervonic acid very difficult.A new combined process of molecular distillation,urea inclusion and solvent crystallization was established to prepare high-purity nervonic acid with the mixed fatty acids obtained after saponification and acidification of Acer truncatum Bunge oil as raw materials.First,according to the difference in the mean free path of fatty acids,molecular distillation was used to separate and remove C16 saturated fatty acid of palmitic acid and four C18-C20 fatty acids of stearic,oleic,linoleic,and linolenic acids.The content of C16-C20 fatty acids decreased from 72.92% to 19.22% after two-stage molecular distillation processes,in which the contents of saturated fatty acid of palmitic acid decreased to about 0.5%.Then,according to the difference in carbon chain length and saturation of fatty acid,the contents of C22-C24 saturated fatty acids of tetracosanoic and docosanoic acids decreased to 0.21% and 0.07% by urea inclusion with urea/free fatty acid preparation by saponification(SPOMFs)ratio as 0.6.In addition,all saturated fatty acids were basically separated.Finally,according to the difference in the solubility of fatty acids in solvents,the C18-C20 unsaturated fatty acids of oleic,linoleic,and linolenic acids and C22 unsaturated fatty acid of erucic acid were removed by solvent crystallization.The content of C18-C20 unsaturated fatty acids decreased to less than 5% with pentanol as the solvent after the first stage solvent crystallization.The content of erucic acid decreased to 3.47% with anhydrous ethanol as the solvent after the second to fifth stage solvent crystallization.The combined process of molecular distillation,urea inclusion and low temperature crystallization innovatively adopted an efficient,simple and easy-toindustrial solvent crystallization method to separate erucic and nervonic acids,obtaining nervonic acid with purity of 96.53% and final yield of 47.99%.
文摘The literature highlights that a severe infection by the fungus Colletotrichum truncatum may be capable of inflicting considerable damage to seeds after harvest, potentially affecting their chemical composition and physiological quality. Taking into account that currently there is no categorization in terms of susceptibility and tolerance on this pathogen, the present work is presented with the main objective of “Evaluate the influence of Pathogenicity of C. truncatum on the physiological quality (germination, vigor, viability) and biochemical components in different varieties of soybean seeds (Glycine max)” most planted in the region. The work was carried out in the Agrotec laboratory, located in the Municipality of San Alberto (Alto Paraná), using a completely randomized experimental design, with AxB factorial arrangement, where A indicates ten most planted soybean varieties in the region and B with or without artificial inoculation of Colletotrichum truncatum, with twenty treatments and four repetitions. The variables evaluated were: germination, vigor, viability and chemical composition. The data were subjected to analysis of variance and the Tukey test at 5% error. The results showed a significant statistical difference, accepting the alternative hypothesis proposed “The pathogenicity of Colletotrichum truncatum influences the physiological quality (germination, vigor, viability) and biochemical components (saturated and unsaturated fatty acids) in different varieties of soybean seeds (Glycine max)”.
基金Supported by Agricultural Elite Cultivar Project of Shandong Province(lkz2014[96])~~
文摘[Objective] Cloning of the AtrMYB transcription factor gene from Acer truncatum was conducted to further explore the red leaf development mechanism and breed cultivars of colored-leaf maple. [Method] The Acer truncatum ‘Luhong No.1' cultivar was used as the material for cloning the MYB gene by mean of RTPCR and RACE-PCR. [Results] Sequence analysis showed that the fragment contained a full coding region of 831 bp encoding 276 amino acid residues with a molecular weight of 32.17 kD and a molecular formula C_(1430)H_(14052)N_(2247)O_(406)S_(14). The gene was named as AtrMYB with a Gen Bank accession number of 1825712. This coded protein had apI of 9.44. The results showed that the AtrMYB exhibited typical features of the R2R3-MYB domain. The AtrMYB was highly homologous with the MYB of other species at nucleotide and amino acid levels. The AtrMYB had no signal peptide, but a nuclear localization signal. The phylogenetic tree showed that the AtrMYB was at the same clade as the MYB from Citrus sinensis. [Conclusion] The AtrMYB was cloned from Acer truncatum ‘Luhong No.1' cultivar. These results have provided a foundation for further purification and identification of target protein and function study of the AtrMYB.
基金Supported by Agricultural Improved Variety Project of Shandong Province(LKZ[2014]No.96)
文摘[Objective] This study aimed to clone and analyze the sequence of CHS gene from Acer truncatum leaves. [Method] Using A. truncatum cultivars No.1-6 as experimental materials, total RNA was extracted from A. truncatum leaves with the modified CTAB method. CHS gene sequences were downloaded from the NCBI and aligned by BLAST. Degenerate primers were designed by DNAMAN and Primer- premier5 to amplify the target band. CHS gene fragment was amplified by RT-PCR and ligated to pMD18-T vector. The identified positive colonies were sequenced. [Result] A 1 365 bp fragment was amplified. Sequence analysis suggested that the obtained fragment encoded 365 amino acids and shared above 90% homology to nucleotide sequence of CHS gene from A. palmatum and A. [Conclusion] In this study, CHS gene was successfully cloned from A. truncatum for the first time, which laid the foundation for efficient utilization of CHS gene.
文摘Plant volatile organic compounds (Biogenic Volatile Organic compounds, referred BVOCs) have a significant impact on the atmospheric environment, air quality and human health. This experiment takes Acer truncatum flowers as the research object, uses solid-phase micro-extraction combine GC-MS (SPME-GC-MS) to detect the main component of volatiles released by the flowers from 10 individual trees of Acer truncatum (Acer truncatum Bunge). The results showed that 37 kinds of volatiles were detected and they are belonged to four types organic compouds, such as terpenoids, alcohols, ketones, esters. According to the analysis of the main components of Acer truncatum flower volatiles includes Fluorene, 4,8 -Dimethyl-1,3 (E), 7-Nonene, (cis, trans)-2,6-Dimethyl-2,4,6-triene-Partenkirchen, Myrcene, Basil hexene, 3-Carene, (E)-Basil, Camphene, Caryophyllene, Linalool, α-Terpinolene, O-cymene, 3-Vinyl-1,2-dimethyl-1, Eucalyptus alcohols and Alcohol vinegar-12. However, there were no significant differences between individual trees in terms of obscure material O-cymene, Eucalyptus alcohols, Alcohol vinegar-12, as well as the significant differences in terms of remaining volatiles.
文摘The use of microbes and microbial products as bioherbicides has been studied for several decades, and combinations of bioherbicides and herbicides have been examined to discover possible synergistic interactions to improve weed control efficacy. Bioassays were conducted to assess possible interactions of the herbicide glufosinate [2-amino-4-(hydroxymethylphosphinyl) butanoic acid] and Colletotrichum truncatum (CT), a fungal bioherbicide to control hemp sesbania (Sesbania exaltata)]. Glufosinate acts as a glutamine synthetase (GS) inhibitor that causes elevated ammonia levels, but the mode of action of CT is unknown. GS has also been implicated in plant defense in certain plant-pathogen interactions. The effects of spray applications of glufosinate (1.0 mM) orbioherbicide (8.0 × 104 conidia ml-1), applied alone or in combination were monitored (88 h time-course) on seedling growth, GS activity and ammonia levels in hypocotyl tissues under controlled environmental conditions. Growth (elongation and fresh weight) and extractable GS activity were inhibited in tissues by glufosinate and glufosinate plus CT treatments as early as 16 h, but CT treatment did not cause substantial growth reduction or GS inhibition until after ~40 h. Generally, ammonia levels in hemp sesbania tissues under these various treatments were inversely correlated with GS activity. Localization of hemp sesbania GS activity on electrophoretic gels indicated a lack of activity after 30 h in glufosinate and glufosinate plus CT-treated tissue. Untreated control tissues contained much lower ammonia levels at 24, 64, and 88 h after treatment than treatments with CT, glufosinate or their combination. CT alone caused elevated ammonia levels only after 64 - 88 h. Glufosinate incorporated in agar at 0.25 mM to 2.0 mM, caused a 10% - 45% reduction of CT colony radial growth, compared to fungal growth on agar without glufosinate, and the herbicide also inhibited sporulation of CT. Although no synergistic interactions were found in the combinations of CT and glufosinate at the concentrations used, further insight on the biochemical action of CT and its interactions with this herbicide on hemp sesbania was achieved.
基金Supported by Agricultural Improved Variety Project of Shandong Province(LKZ[2012]No.213,LKZ[2014]No.96)
文摘[ Objective] This study aimed to establish DNA fingerprints of 23 Acer truncatum clones, thus providing the theoretical basis for selection, classification and identification of A. truncatum varieties. [Method] Sixteen pairs of SRAP primers with rich polymorphism and high specificity were used to establish DNA fin-gerprints. [Result] A total of 223 bands were amplified with 16 primer pairs, including 197 polymorphic bands. Averagely 13.9 loci and 12.3 polymorphic loci were amplified with each primer pair. The average percentage of polymorphic loci reached 88. 34% . [ Conclusion] The classification result drawn by cluster analy-sis is consistent with that obtained based on main characteristics and genetic relationships of A. truncatum, clones. By using DNA fingerprints established with prim-er pairs ME1-EM4 and ME2-EM1, 23 A. truncatum clones can be effectively distinguished, and the confidence probability is greater than 99.99%.
文摘Colletotrichum truncatum, grown on rice grain (3 to 4 weeks, 22°C to 24°C) produced a fungus-infested rice mixture of microsclerotia and conidia (spores) in a ratio of ~9:1, respectively. Greenhouse tests of this formulation (0.4 to 50 mg finely-ground fungus-rice product) which applied pre-emergence to 5 cm2 of soil surface, caused 22% to 96% hemp sesbania plant mortality, after 14 days. Post-emergence treatment (fungus-rice aqueous formulation;2.4 × 105 microsclerotia ml-1, 30% unrefined corn oil and 0.2% Silwet L-77 surfactant) of weeds surviving the pre-emergence application, resulted in 93% mortality, after 14 days. Based on greenhouse results, field tests were undertaken: 1) pre-emergence treatment (fungus-rice formulation at 2.4 × 105 microsclerotia cm-2), 2) post-emergence (fungus-rice product in 30% unrefined corn oil, 0.2% Silwet) only treatment, applied 15 days after planting and 3) pre-emergence treatment followed by post-emergence treatment (fungus-rice product in 30% unrefined corn oil, 0.2% Silwet) applied 15 days after planting to surviving weeds. Control treatments were: 1) autoclaved rice product sans fungus, 2) unrefined corn oil (30% unrefined corn oil, 0.2% Silwet in water) and 3) untreated plants. Planting dates were: early season (April-May), early-mid season (June-July), late-mid season (July-August), and late season (September-October). Weed mortality was recorded at 15 days for the pre-plus post-treatment, and at 30 days after planting for the pre-emergence only and the post-treatment only. The early season, pre-emergence treatment caused 67% hemp sesbania mortality (3-yr average) within 15 days and the post-emergence treatment caused 91% mortality of the surviving weeds. In the late-mid-season, pre-emergence treatment caused minimal (<5%) mortality at 15 days, but mortality in the post-emergence treatment was >80%. Results suggest that seasonal environmental conditions are important in the efficacy of this C. truncatum-rice product formulation when applied pre- or post-emergence to this onerous weed.
基金Supported by Project of Agricultural Fine Varieties of Shandong Province[LKNZ(2012)No.213]
文摘Leaves of Acer truncatum ' Luhong No. 1 ' contain large amounts of polysaccharides and polyphenols, which seriously affect extraction yield and quality of total RNA. In order to explore the appropriate total RNA extraction method, total RNA was extracted from leaves of A. truncatum ' Luhong No. 1 ' with three methods, including kit method, Trizol method and modified CTAB method. The results showed that ODE6o/OD2so and OD^o/OD2ao ratios of total RNA extracted from leaves of A. truncatum ' Luhong No. 1 ' with kit method were higher than 1.8, with a general yield and certain level of DNA contamination ; OD^o/OD~ and OD^o/OD^o ratios of total RNA extracted with Trizol method were about 1.5, with the lowest yield; OD260/OD280 and OD260/OD230 ratios of total RNA extracted with modified CTAB method were about 2.0, with the highest yield and distinct eleetrophoresis patterns. The results demonstrated that total RNA extracted with modified CTAB method exhibited high yield and purity, which could meet the demands of subsequent molecular biology research. Thus, modified CTAB method is the appro- oriate method for extracting total RNA from leaves of A. truncatum ' Luhong No. 1 '