PGIP gene was obtained from Brassica oleracea L. var. alboglabra, named BoPGIP2. The full length of BoPGIP2 gene is 1 102 bp and the exon is 993 bp which encodes a protein of 330 amino acids with a predicted molecular...PGIP gene was obtained from Brassica oleracea L. var. alboglabra, named BoPGIP2. The full length of BoPGIP2 gene is 1 102 bp and the exon is 993 bp which encodes a protein of 330 amino acids with a predicted molecular mass of 37.1 kDa, interrupted by one intron of 95 bp in, length. Sequence analysis revealed that it has five potential N-giycosylation sites, two protein kinase C phosphrylation sites, five casin kinase Ⅱ phosphrylation sites and four N-myristoylation sites. The amino acids sequences alignment confirmed that ^145 LRR stucture was highly conserved in all aligned PGIP sequences.展开更多
Cowpea Trypsin Inhibitor (CpTI) gene was transferred into the cotyle dons and hypocotyls of cauliflower by Agrobacterium-mediated transformation met hod. The best selective concentration of kanamycin (kan) was 15 mg L...Cowpea Trypsin Inhibitor (CpTI) gene was transferred into the cotyle dons and hypocotyls of cauliflower by Agrobacterium-mediated transformation met hod. The best selective concentration of kanamycin (kan) was 15 mg L-1. The con centration of carbencillin (carb) was 500 mg L-1. 14 transgenic cauliflower pla nts were obtained. The putative transformants were assayed by PCR and Southern b lotting analysis. The results indicated that CpTI gene was transferred into caul iflower successfully.展开更多
The dominant genic male sterility （DGMS） gene CDMs399-3 derived from a spontaneous mutation in the line 79-399-3 of spring cabbage （Brassica oleracea var. capitata L.）, has been successfully applied in hybrid seed...The dominant genic male sterility （DGMS） gene CDMs399-3 derived from a spontaneous mutation in the line 79-399-3 of spring cabbage （Brassica oleracea var. capitata L.）, has been successfully applied in hybrid seed production of several cabbage cultivars in China. During the development of dominant male sterility lines in cabbage, the conventional identification of homozygous male-sterile plants （CDMs399-3/CDMs399-3） is a laborious and time-consuming process. For marker-assisted selection （MAS） of the gene CDMs399-3 transferred into key spring cabbage line 397, expressed sequence tag-simple sequence repeats （EST-SSR） and SSR technology were used to identify markers that were linked to CDMs399-3 based on method of bulked segregant analysis （BSA）. By screening a set of 978 EST-SSRs and 395 SSRs, a marker BoE332 linked to the CDMs399-3 at a distance of 3.6 cM in the genetic background of cabbage line 397 were identified. 7 homozygons male-sterile plants in population P1170 with 20 plants were obtained finally via MAS of BoE332. Thus, BoE332 will greatly facilitate the transferring of the gene CDMs399-3 into the key spring cabbage line 397 and improve the application of DGMS in cabbage hybrid breeding.展开更多
The purpose of the present studies was analysis of the age induced changes in photochemical efficiency and xanthophyils cycle pigments of the primary cabbage （Brassica oleracea L. cv. Capitata f. alba） leaves. Photo...The purpose of the present studies was analysis of the age induced changes in photochemical efficiency and xanthophyils cycle pigments of the primary cabbage （Brassica oleracea L. cv. Capitata f. alba） leaves. Photochemical efficiency of photosystem Ⅱ （PS Ⅱ） was studied by a pulse amplitude modulated chlorophyll fluorescence apparatus, chlorophyll concentration was analysis spectrophotometrically and xanthophyll cycle pigments were estimated by high-pressure liquid chromatography （HPLC）. Leaf senescence was accompanied with a decrease both in chlorophylls concentration, the photochemical efficiency and rate constant for PS Ⅱ photochemistry whereas non-photochemical parameters increased. Excitation pressure （1-qP） which is a measure of relative lumen acidification increased by 1.2x in aging leaves. The maximum quantum yield of PS Ⅱ showed no significant change. The level of de-epoxidised xanthophylls increased but the concentration of mono- and di-epoxy xanthophylls decreased in aging leaves. A linear relationship between the excitation pressure and the depoxidation state of the xanthophyll cycle pigments and lutein, during the onset of senescence suggests that excitation pressure can be used as a sensor for monitoring the onset of senescence as well for the de-epoxidation state of the xanthophylls responsible for non-photochemical quenching in stressed leaves.展开更多
Carotenoids and chlorophylls are among the most widely distributed pigments in nature that play essential roles in the photosynthetic apparatus and confer diverse colours in plants.Among all vegetables,cauliflower(Bra...Carotenoids and chlorophylls are among the most widely distributed pigments in nature that play essential roles in the photosynthetic apparatus and confer diverse colours in plants.Among all vegetables,cauliflower(Brassica oleracea L.ssp.var.botrytis)is rich in phytochemicals and is an important crop grown all over the world.This study investigates carotenoid and chlorophyll concentrations in differently pigmented cultivars and elucidates the role of transcriptional regulation of carotenoid accumulation including lutein andβ-carotene.Here,we characterised changes in pigments by UHPLC-DAD-ToF-MS and changes in transcript levels of carotenoid metabolic genes by qRT-PCR in florets and leaves of orange(‘Jaffa'and‘Sunset'),purple(‘Di Sicilia Violetto'and‘Graffiti'),green(‘Trevi')and white(‘Clapton')cultivars.Transcript levels of all carotenoid metabolic genes showed different transcript level patterns in the leaves and florets.Compared to the other cultivars,the orange cultivars had the highest levels ofβ-carotene in the florets and lutein in the leaves resulting in changes lutein/β-carotene ratios.In the green cultivar,higher transcript levels were also found,especially for phytoene synthase and phytoene desaturase genes of the core biosynthesis pathway.However,no increased carotenoid concentrations were observed,possibly due to a higher carotenoid turnover induced by the carotenoid cleavage dioxygenase 4 in the green cultivar.In the white(‘Clapton')and purple(‘Di Sicilia Violetto'and‘Graffiti')cultivars the phytoene desaturase transcript levels as well as carotenoid concentrations were low.Chlorophyll concentrations changed in trend comparable to the carotenoid concentrations and were only significantly lower in the leaves of the orange cultivar‘Jaffa'.Also,the chlorophyll a/b ratio changed in‘Jaffa'.In florets the highest chlorophylls concentrations were observed for the green cultivar(‘Trevi')and the purple cultivar(‘Di Sicilia Violetto').Taken together,the study demonstrates the complex source-sink relationship of carotenoid accumulation in different coloured cauliflower.展开更多
SSR analysis on genetic diversity of 30 samples was carried out. Five primers selected from 36 primers were used to amplify 30 samples in this experiment, PCR products were separated by 6% polyacrylamide gel electroph...SSR analysis on genetic diversity of 30 samples was carried out. Five primers selected from 36 primers were used to amplify 30 samples in this experiment, PCR products were separated by 6% polyacrylamide gel electrophoresis, silver staining and photographed. The results of SSR were analyzed by UPGMA clustering. The results showed that a total of 21 gene alleles were detected by 5 SSR primers. The number of alleles ranged from 2 to 5 with an average of 4.2.PIC range was 0.257-0.92 1, with an average of 0.543. The average coefficient of genetic similarity of SSR markers among materials was 0.432. Some of cabbage cultivars in the experiment were divided into four groups except cultivars which come from Japan.展开更多
Cytoplasmic male sterility (CMS) is a maternally inherited trait that prevents the production of function pollen, but maintains female fertility. It has been widely used in breeding programs to product F_1 hybrid seed
[Objective] The purpose of this study is to determine the effects of com-bined use of boron and manganese fertilizers on the nutritional quality and physio-logical indices of Brassica campestris. [Method] In the nutri...[Objective] The purpose of this study is to determine the effects of com-bined use of boron and manganese fertilizers on the nutritional quality and physio-logical indices of Brassica campestris. [Method] In the nutrient solutions for growing B. campestris by hydroponics, boric acid and manganese sulfate were added at 0.5, 2.5, and 7.5 mg/L respectively. Another treatment without boron and manganese was prepared as the control. Quality and physiological indices of B. campestris in the 10 treatments were measured. [Result] Boron and manganese shared obvious in-teraction in improving the quality and physiological indices of B. campestris. To cul-tivate B. campestris with high quality and strong resistance, the optimum concentra-tions of boron and manganese in the nutrient solution should be 2.5 mg/L boric acid and 2.5-7.5 mg/L manganese sulfate. [Conclusion] The findings wil provide refer-ence for studying effects of trace elements on nutrient composition of vegetables.展开更多
Glucosinolates （GSs） are a group of plant secondary metabolites containing abundant nitrogen （N） and sulfur （S） mainly in Brassica and have the beneficial effects on human health including anti-carcinogenic, cho...Glucosinolates （GSs） are a group of plant secondary metabolites containing abundant nitrogen （N） and sulfur （S） mainly in Brassica and have the beneficial effects on human health including anti-carcinogenic, cholesterol-reducing and other pharmacological effects. The objective of this study was to investigate the effect of different concentrations of N （5, 10, and 20 mmol L-a, denoted by N5, N10 and N20） and S （0,5, 1, and 2 mmol L^-1, denoted by S0.5, S1 and S2） on the yield and GSs in pakchoi （Brassica campestris L. ssp. chinensis var. communis） in hydroponics. Results showed that N10 and N20 significantly enhanced the yield compared with N5, however, N20 had a negative effect relative to N10. Only with N10 and N20 low S supply （S0.5） reduced the yield. The concentrations of aliphatic GSs, aromatic GS and total GSs were enhanced by N5 and indolyl GSs were enhanced by N20. S2 enhanced the concentration of individual GS and total GSs. The concentrations of indolyl GSs were maximized in N20S2 treatment, whereas the highest concentrations of aliphatic GSs, aromatic GS and total GSs were found in N5S2 treatment. Effects of N and S on aliphatic GSs were higher than on indolyl GSs. The results suggest that the accumulation of aliphatic GSs and aromatic GS could be enhanced by low N and high S and restricted by high N while that of indolyl GSs could be enhanced by high N and high S.展开更多
This article investigates the responses of Brassica campestris seedlings to an acute level of nitrogen dioxide （NO2） exposure in a plant growth chamber, and examines whether pretreating plants with hydrogen peroxide...This article investigates the responses of Brassica campestris seedlings to an acute level of nitrogen dioxide （NO2） exposure in a plant growth chamber, and examines whether pretreating plants with hydrogen peroxide （H2O2） will alleviate NO2-caused injury. Twenty-eight-day-old B. campestris plants sprayed with 10 mmol L^-1 H2O2 aqueous solution （corresponding to approximate 1.0 mg H2O2 per single plant） were exposed to different concentrations of NO2 （0.25, 0.5, 1.0, and 2.0 μL L^-1, respectively） for 24 h under controlled environment. To measure the plant biomass, the plants were fumigated with the same NO2 concentrations as mentioned above for 7 h per day （8.00-15.00） for 7 days. As a control, charcoal filtered air alone was applied. Data were collected on plant biomass, total chlorophyll, photosynthetic rate, stomatal conductance, nitrate and nitrate reductase （NR）, antioxidative enzymes, ascorbate （ASA）, and malondialdehyde （MDA）, immediately after exposure. The results showed that exposure to a moderate dose of NO2 （e.g., 0.25 μL L^-1） had a favorable effect on plants, and the dry weight of the above-ground part increased, whereas the exposure to high NO2 concentrations （e.g., 0.5 μL L^-1 or higher） caused a reduction in the plant biomass and the total chlorophyll, when compared with the control. In addition, at 0.5 μL L^-1 or higher NO2 concentrations, prominent increases in the MDA level and superoxide dismutase （SOD） and NR activities were observed. Exposure to 1 μL L^-1 and higher NO2 resulted in necroses appearing on older leaves, and an increase in catalase （CAT） activity, decrease in ASA content, increased accumulation of NO3^-, and reduction in photosynthesis, when compared with the controls. No changes were detected in stomatal conductance under NO2 fumigation. The pretreatment with 10 mmol L^-1 H2O2 alleviated significantly NO2- caused biomass decrease and photosynthetic inhibition when compared with H2O2-untreated plants. Under NO2 fumigation, further induction in SOD and CAT activities occurred in H2O2 treated plants when compared with H2O2- untreated plants. The effect of NO2 on the ASA and MDA contents was also absent in H2O2-treated plants. However, the H2O2 treatment did not alter the nitrate content and NR activity in plants under NO2 fumigation. The H2O2 treatment caused a lower rate of stomatal conductance. Taken together, these data suggest that fumigation with an acute level of NO2 causes oxidative damage to B. campestris seedlings. The H2O2 pretreatment markedly protects plants against NO2 stress and this may be associated with inducible antioxidative level. NO2 fumigation contributes, at least in part, to the enhanced levels of nitrate in B. campestris leaves.展开更多
Collard variety( Brassis oleracea L. var. acephala f. tricolor Hort.) as a research material was treated with exogenous H_2O_2 and H_2O_2 scavenger dimethyl thiourea under 100 mmol/L NaC l stress. Two days later,growt...Collard variety( Brassis oleracea L. var. acephala f. tricolor Hort.) as a research material was treated with exogenous H_2O_2 and H_2O_2 scavenger dimethyl thiourea under 100 mmol/L NaC l stress. Two days later,growth rate,dry weight,fresh weight and relative water content of the plants were determined. After 6h of treatment,the activity and gene expression of three antioxidant enzymes,superoxide dismutase( SOD),catalase( CAT) and ascorbate peroxidase( APX) in plants,were measured. The results showed that the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in collard seedlings were higher in the treatment of salt stress with the addition of 0. 05 mmol/L exogenous H_2O_2 than in the simple salt stress treatment; and when endogenous H_2O_2 was removed,the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in plant seedlings were lower than those under simple salt stress. It is speculated that under salt stress,H_2O_2 is involved in the regulation of antioxidant defense gene expression,and it might be an important regulator of salt-induced antioxidant system in collard leaves.展开更多
In order to establish a rapid propagation system for Brassica campestris L. ssp. chinensis var. utilis, the anther and cotyledon-cotyledonary petioles were used as explants to conduct tissue culture research. The resu...In order to establish a rapid propagation system for Brassica campestris L. ssp. chinensis var. utilis, the anther and cotyledon-cotyledonary petioles were used as explants to conduct tissue culture research. The results showed that not bloomed flower buds with higher styles than petals were appropriate for anther cul- ture. Moreover, most microspores were at the mid-late uninucleate stage at that time. The pollen germination rates of Brassica campestris L. ssp. chinensis var. u- tills were low and the germination rates in autumn and winter were higher than that in summer. The induction medium of anther callus of Brassica campestris L. ssp. chinensis var. utilis was MS＋1.0 mg/L KT＋1.0 mg/L 2, 4-D＋3% sugar＋6 g/L agar＋ 8% coconut milk and the induction media of adventitious bud were MS＋2.0 mg/L 6-BA＋ 0.5 mg/L NAA＋I.0 g/L activated carbon＋2% sugar＋6 g/L agar or MS＋2.0 mg/L ZT＋ 0.5 mg/L IAA＋0.5 g/L AgNO3＋1.0 g/L activated carbon＋2% sugar＋6 g/L agar. The induction percentage of adventitious bud by anther culture was 36.7%. Browning phenomenon appeared during the culture of adventitious bud and regeneration plant could not be formed. The plant regeneration rate reached 80% when cotyledon- cotyledonary petioles were used as explant.展开更多
基金Supported by School High-level Talent Starting Fund of Qingdao Agriculture University:Studies on Clone and Evolution of PGIPGene from Brassica crops(630745)~~
文摘PGIP gene was obtained from Brassica oleracea L. var. alboglabra, named BoPGIP2. The full length of BoPGIP2 gene is 1 102 bp and the exon is 993 bp which encodes a protein of 330 amino acids with a predicted molecular mass of 37.1 kDa, interrupted by one intron of 95 bp in, length. Sequence analysis revealed that it has five potential N-giycosylation sites, two protein kinase C phosphrylation sites, five casin kinase Ⅱ phosphrylation sites and four N-myristoylation sites. The amino acids sequences alignment confirmed that ^145 LRR stucture was highly conserved in all aligned PGIP sequences.
文摘Cowpea Trypsin Inhibitor (CpTI) gene was transferred into the cotyle dons and hypocotyls of cauliflower by Agrobacterium-mediated transformation met hod. The best selective concentration of kanamycin (kan) was 15 mg L-1. The con centration of carbencillin (carb) was 500 mg L-1. 14 transgenic cauliflower pla nts were obtained. The putative transformants were assayed by PCR and Southern b lotting analysis. The results indicated that CpTI gene was transferred into caul iflower successfully.
基金supported by the National Science and Technology Ministry of China (2008BADB1B02 and 2009BADB8B03)the Core Research Budget of the Non-profit Governmental Research Institution (ICS, CAAS) (1610032011011)+1 种基金the China Agriculture Research System (CARS-25)the National High Technology Research and Development Program of China (863 Program, 2012AA100101)
文摘The dominant genic male sterility （DGMS） gene CDMs399-3 derived from a spontaneous mutation in the line 79-399-3 of spring cabbage （Brassica oleracea var. capitata L.）, has been successfully applied in hybrid seed production of several cabbage cultivars in China. During the development of dominant male sterility lines in cabbage, the conventional identification of homozygous male-sterile plants （CDMs399-3/CDMs399-3） is a laborious and time-consuming process. For marker-assisted selection （MAS） of the gene CDMs399-3 transferred into key spring cabbage line 397, expressed sequence tag-simple sequence repeats （EST-SSR） and SSR technology were used to identify markers that were linked to CDMs399-3 based on method of bulked segregant analysis （BSA）. By screening a set of 978 EST-SSRs and 395 SSRs, a marker BoE332 linked to the CDMs399-3 at a distance of 3.6 cM in the genetic background of cabbage line 397 were identified. 7 homozygons male-sterile plants in population P1170 with 20 plants were obtained finally via MAS of BoE332. Thus, BoE332 will greatly facilitate the transferring of the gene CDMs399-3 into the key spring cabbage line 397 and improve the application of DGMS in cabbage hybrid breeding.
文摘The purpose of the present studies was analysis of the age induced changes in photochemical efficiency and xanthophyils cycle pigments of the primary cabbage （Brassica oleracea L. cv. Capitata f. alba） leaves. Photochemical efficiency of photosystem Ⅱ （PS Ⅱ） was studied by a pulse amplitude modulated chlorophyll fluorescence apparatus, chlorophyll concentration was analysis spectrophotometrically and xanthophyll cycle pigments were estimated by high-pressure liquid chromatography （HPLC）. Leaf senescence was accompanied with a decrease both in chlorophylls concentration, the photochemical efficiency and rate constant for PS Ⅱ photochemistry whereas non-photochemical parameters increased. Excitation pressure （1-qP） which is a measure of relative lumen acidification increased by 1.2x in aging leaves. The maximum quantum yield of PS Ⅱ showed no significant change. The level of de-epoxidised xanthophylls increased but the concentration of mono- and di-epoxy xanthophylls decreased in aging leaves. A linear relationship between the excitation pressure and the depoxidation state of the xanthophyll cycle pigments and lutein, during the onset of senescence suggests that excitation pressure can be used as a sensor for monitoring the onset of senescence as well for the de-epoxidation state of the xanthophylls responsible for non-photochemical quenching in stressed leaves.
基金supported by the Federal Office for Agriculture and Food(BLE)of Germany[Grant No.2816DOKI07(Carcauli)]。
文摘Carotenoids and chlorophylls are among the most widely distributed pigments in nature that play essential roles in the photosynthetic apparatus and confer diverse colours in plants.Among all vegetables,cauliflower(Brassica oleracea L.ssp.var.botrytis)is rich in phytochemicals and is an important crop grown all over the world.This study investigates carotenoid and chlorophyll concentrations in differently pigmented cultivars and elucidates the role of transcriptional regulation of carotenoid accumulation including lutein andβ-carotene.Here,we characterised changes in pigments by UHPLC-DAD-ToF-MS and changes in transcript levels of carotenoid metabolic genes by qRT-PCR in florets and leaves of orange(‘Jaffa'and‘Sunset'),purple(‘Di Sicilia Violetto'and‘Graffiti'),green(‘Trevi')and white(‘Clapton')cultivars.Transcript levels of all carotenoid metabolic genes showed different transcript level patterns in the leaves and florets.Compared to the other cultivars,the orange cultivars had the highest levels ofβ-carotene in the florets and lutein in the leaves resulting in changes lutein/β-carotene ratios.In the green cultivar,higher transcript levels were also found,especially for phytoene synthase and phytoene desaturase genes of the core biosynthesis pathway.However,no increased carotenoid concentrations were observed,possibly due to a higher carotenoid turnover induced by the carotenoid cleavage dioxygenase 4 in the green cultivar.In the white(‘Clapton')and purple(‘Di Sicilia Violetto'and‘Graffiti')cultivars the phytoene desaturase transcript levels as well as carotenoid concentrations were low.Chlorophyll concentrations changed in trend comparable to the carotenoid concentrations and were only significantly lower in the leaves of the orange cultivar‘Jaffa'.Also,the chlorophyll a/b ratio changed in‘Jaffa'.In florets the highest chlorophylls concentrations were observed for the green cultivar(‘Trevi')and the purple cultivar(‘Di Sicilia Violetto').Taken together,the study demonstrates the complex source-sink relationship of carotenoid accumulation in different coloured cauliflower.
文摘SSR analysis on genetic diversity of 30 samples was carried out. Five primers selected from 36 primers were used to amplify 30 samples in this experiment, PCR products were separated by 6% polyacrylamide gel electrophoresis, silver staining and photographed. The results of SSR were analyzed by UPGMA clustering. The results showed that a total of 21 gene alleles were detected by 5 SSR primers. The number of alleles ranged from 2 to 5 with an average of 4.2.PIC range was 0.257-0.92 1, with an average of 0.543. The average coefficient of genetic similarity of SSR markers among materials was 0.432. Some of cabbage cultivars in the experiment were divided into four groups except cultivars which come from Japan.
文摘Cytoplasmic male sterility (CMS) is a maternally inherited trait that prevents the production of function pollen, but maintains female fertility. It has been widely used in breeding programs to product F_1 hybrid seed
基金Supported by a grant from Ministry of Science and Technology for the Project of Science and Technology Talents Serving in Enterprise(2009GJC50042)~~
文摘[Objective] The purpose of this study is to determine the effects of com-bined use of boron and manganese fertilizers on the nutritional quality and physio-logical indices of Brassica campestris. [Method] In the nutrient solutions for growing B. campestris by hydroponics, boric acid and manganese sulfate were added at 0.5, 2.5, and 7.5 mg/L respectively. Another treatment without boron and manganese was prepared as the control. Quality and physiological indices of B. campestris in the 10 treatments were measured. [Result] Boron and manganese shared obvious in-teraction in improving the quality and physiological indices of B. campestris. To cul-tivate B. campestris with high quality and strong resistance, the optimum concentra-tions of boron and manganese in the nutrient solution should be 2.5 mg/L boric acid and 2.5-7.5 mg/L manganese sulfate. [Conclusion] The findings wil provide refer-ence for studying effects of trace elements on nutrient composition of vegetables.
文摘Glucosinolates （GSs） are a group of plant secondary metabolites containing abundant nitrogen （N） and sulfur （S） mainly in Brassica and have the beneficial effects on human health including anti-carcinogenic, cholesterol-reducing and other pharmacological effects. The objective of this study was to investigate the effect of different concentrations of N （5, 10, and 20 mmol L-a, denoted by N5, N10 and N20） and S （0,5, 1, and 2 mmol L^-1, denoted by S0.5, S1 and S2） on the yield and GSs in pakchoi （Brassica campestris L. ssp. chinensis var. communis） in hydroponics. Results showed that N10 and N20 significantly enhanced the yield compared with N5, however, N20 had a negative effect relative to N10. Only with N10 and N20 low S supply （S0.5） reduced the yield. The concentrations of aliphatic GSs, aromatic GS and total GSs were enhanced by N5 and indolyl GSs were enhanced by N20. S2 enhanced the concentration of individual GS and total GSs. The concentrations of indolyl GSs were maximized in N20S2 treatment, whereas the highest concentrations of aliphatic GSs, aromatic GS and total GSs were found in N5S2 treatment. Effects of N and S on aliphatic GSs were higher than on indolyl GSs. The results suggest that the accumulation of aliphatic GSs and aromatic GS could be enhanced by low N and high S and restricted by high N while that of indolyl GSs could be enhanced by high N and high S.
基金the National Natural Science Foundation of China （30570445） Natural Science Foundation of Liaoning Province, China （20021022）+1 种基金 Tackle Key Problem of Science and Technology, Education Department of Liaoning Province, China （2004D005）and Director Foundation of ExperimentalCentre, Shenyang Normal University, China （SY200406）.
文摘This article investigates the responses of Brassica campestris seedlings to an acute level of nitrogen dioxide （NO2） exposure in a plant growth chamber, and examines whether pretreating plants with hydrogen peroxide （H2O2） will alleviate NO2-caused injury. Twenty-eight-day-old B. campestris plants sprayed with 10 mmol L^-1 H2O2 aqueous solution （corresponding to approximate 1.0 mg H2O2 per single plant） were exposed to different concentrations of NO2 （0.25, 0.5, 1.0, and 2.0 μL L^-1, respectively） for 24 h under controlled environment. To measure the plant biomass, the plants were fumigated with the same NO2 concentrations as mentioned above for 7 h per day （8.00-15.00） for 7 days. As a control, charcoal filtered air alone was applied. Data were collected on plant biomass, total chlorophyll, photosynthetic rate, stomatal conductance, nitrate and nitrate reductase （NR）, antioxidative enzymes, ascorbate （ASA）, and malondialdehyde （MDA）, immediately after exposure. The results showed that exposure to a moderate dose of NO2 （e.g., 0.25 μL L^-1） had a favorable effect on plants, and the dry weight of the above-ground part increased, whereas the exposure to high NO2 concentrations （e.g., 0.5 μL L^-1 or higher） caused a reduction in the plant biomass and the total chlorophyll, when compared with the control. In addition, at 0.5 μL L^-1 or higher NO2 concentrations, prominent increases in the MDA level and superoxide dismutase （SOD） and NR activities were observed. Exposure to 1 μL L^-1 and higher NO2 resulted in necroses appearing on older leaves, and an increase in catalase （CAT） activity, decrease in ASA content, increased accumulation of NO3^-, and reduction in photosynthesis, when compared with the controls. No changes were detected in stomatal conductance under NO2 fumigation. The pretreatment with 10 mmol L^-1 H2O2 alleviated significantly NO2- caused biomass decrease and photosynthetic inhibition when compared with H2O2-untreated plants. Under NO2 fumigation, further induction in SOD and CAT activities occurred in H2O2 treated plants when compared with H2O2- untreated plants. The effect of NO2 on the ASA and MDA contents was also absent in H2O2-treated plants. However, the H2O2 treatment did not alter the nitrate content and NR activity in plants under NO2 fumigation. The H2O2 treatment caused a lower rate of stomatal conductance. Taken together, these data suggest that fumigation with an acute level of NO2 causes oxidative damage to B. campestris seedlings. The H2O2 pretreatment markedly protects plants against NO2 stress and this may be associated with inducible antioxidative level. NO2 fumigation contributes, at least in part, to the enhanced levels of nitrate in B. campestris leaves.
基金Supported by Science and Technology Development Planning Project of Henan Province(182102110305)
文摘Collard variety( Brassis oleracea L. var. acephala f. tricolor Hort.) as a research material was treated with exogenous H_2O_2 and H_2O_2 scavenger dimethyl thiourea under 100 mmol/L NaC l stress. Two days later,growth rate,dry weight,fresh weight and relative water content of the plants were determined. After 6h of treatment,the activity and gene expression of three antioxidant enzymes,superoxide dismutase( SOD),catalase( CAT) and ascorbate peroxidase( APX) in plants,were measured. The results showed that the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in collard seedlings were higher in the treatment of salt stress with the addition of 0. 05 mmol/L exogenous H_2O_2 than in the simple salt stress treatment; and when endogenous H_2O_2 was removed,the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in plant seedlings were lower than those under simple salt stress. It is speculated that under salt stress,H_2O_2 is involved in the regulation of antioxidant defense gene expression,and it might be an important regulator of salt-induced antioxidant system in collard leaves.
基金Supported by Guangdong Key Base Project of Scientific Research(2013A061401019)Application Basis Project of Scientific and Informational Bureau in Guangzhou(2010Y1-C831)Pearl River S&T Nova Program of Guangzhou(2013J2200086)~~
文摘In order to establish a rapid propagation system for Brassica campestris L. ssp. chinensis var. utilis, the anther and cotyledon-cotyledonary petioles were used as explants to conduct tissue culture research. The results showed that not bloomed flower buds with higher styles than petals were appropriate for anther cul- ture. Moreover, most microspores were at the mid-late uninucleate stage at that time. The pollen germination rates of Brassica campestris L. ssp. chinensis var. u- tills were low and the germination rates in autumn and winter were higher than that in summer. The induction medium of anther callus of Brassica campestris L. ssp. chinensis var. utilis was MS＋1.0 mg/L KT＋1.0 mg/L 2, 4-D＋3% sugar＋6 g/L agar＋ 8% coconut milk and the induction media of adventitious bud were MS＋2.0 mg/L 6-BA＋ 0.5 mg/L NAA＋I.0 g/L activated carbon＋2% sugar＋6 g/L agar or MS＋2.0 mg/L ZT＋ 0.5 mg/L IAA＋0.5 g/L AgNO3＋1.0 g/L activated carbon＋2% sugar＋6 g/L agar. The induction percentage of adventitious bud by anther culture was 36.7%. Browning phenomenon appeared during the culture of adventitious bud and regeneration plant could not be formed. The plant regeneration rate reached 80% when cotyledon- cotyledonary petioles were used as explant.
