[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
A molecular genetic map of Chinese cabbage was constructed with a 102 recombinant inbred (RI) population from a cross of two cultivated Chinese cabbage lines 177 and 276, using AFLP and RAPD markers. 352 markers inclu...A molecular genetic map of Chinese cabbage was constructed with a 102 recombinant inbred (RI) population from a cross of two cultivated Chinese cabbage lines 177 and 276, using AFLP and RAPD markers. 352 markers including 265 AFLP markers and 87 RAPD markers were integrated into 17 linkage groups. It covered a total of 2 665. 7 cM with an average interval of 7. 6 cM. AFLP marker is efficient for map construction while it easily forms clusters to cause big gaps in map. A total of 13.92 % abnormal segregation markers distributed in the map. The molecular genetic map is fundamental for gene localization, comparative genomics, and QTL mapping of important agronomic traits.展开更多
The study analyzed the silencing of BcMF12 gene regulated by BcA9 promoter in the transgenic pakchoi and confirmed the effect of antisense BcMF12 gene on the pollen development. A conserved BcMF12 gene fragment was am...The study analyzed the silencing of BcMF12 gene regulated by BcA9 promoter in the transgenic pakchoi and confirmed the effect of antisense BcMF12 gene on the pollen development. A conserved BcMF12 gene fragment was amplified from the cDNA of flower buds in pakchoi (Brassica campestris L. ssp. chinensis, syn. B. rapa L. ssp. chinensis) and was fused to the anther specific BcA9 promoter. The plant antisense expression vector was constructed and then introduced into pakchoi via Agrobacterium-mediated transformation. The transgenic plants were screened by antibiotics and molecular analysis. PCR and Southern blot revealed that the antisense BcMF12-GUS fusion gene regulated by BcA9 promoter was integrated into transgenic plants. Northern blot suggested that the expression of BcMF12 gene was down-regulated significantly. The pollen germination rate of transgenic plants with antisense BcMF12 gene decreased as compared with that of the control plants. The expression of the gene BcMF12 related to the pollen development was inhibited by the antisense BcMF12 driven by BcA9 promoter, which consequently affected the pollen development in pakchoi.展开更多
We conducted plant growth experiments in microbe-free vermiculite to study the effects of four types of fermented seaweed liquid fertilizer (SLF) made from nori (Pyropia yezoensis) seaweed on the germination, plant gr...We conducted plant growth experiments in microbe-free vermiculite to study the effects of four types of fermented seaweed liquid fertilizer (SLF) made from nori (Pyropia yezoensis) seaweed on the germination, plant growth characteristics, SPAD value, and nutrient content and uptake of komatsuna (Brassica rapa L. var. wakana komatsuna). The four types of fermented nori SLF used in this study were prepared by anaerobic fermentation of unwashed nori (SLF1), aerobic fermentation of unwashed nori (SLF2), anaerobic fermentation of washed nori (SLF3), and aerobic fermentation of washed nori (SLF4). Komatsuna seeds treated with 200-, 300-, and 400-fold dilutions of SLFs exhibited improved relative germination ratios (RGRs) at 3 and 4 days after sowing (DAS). At 4 DAS, the RGRs of seeds treated with 10-, 100-, 200-, 300-, and 400-fold SLF dilutions showed no differential effect. Seeds treated with undiluted SLFs did not germinate by 4 DAS. SLF1 may promote komatsuna seed germination. The nitrogen (N), calcium, magnesium, sodium (Na), and iodine (I) contents of plants treated with SLF1 were significantly increased relative to plants treated with the other SLFs. Moreover, the I and Na contents of plants were significantly increased by foliar spray application of different dilutions of SLF1. However, SLF treatment markedly reduced the shoot dry weight compared with 1/2-strength modified Hoagland nutrient (MHN) solution, although the same amounts of N and K were applied. SPAD values of the plants treated with SLFs were significantly higher than those of plants treated with MHN. Foliar treatment with SLFs had no significant effect on plant growth, SPAD value, or uptake of nutrients (except Na) relative to the control, but the I content was increased. Plants treated with SLF1 and SLF2 exhibited the highest Na uptake. Foliar spray treatments with SLF1 resulted in the highest I contents in plants. Based on our results, SLF1 is suitable for use as a liquid fertilizer to promote germination and increase nutrient content in komatsuna. These results need to be followed up in soil experiments in the presence of microbes in the rhizosphere.展开更多
The effects of different Cd (Cadmium) levels on generation of active oxygen speceies(AOS) and H2O2-scavenging system in the leaves of Brassica campestris L. ssp. chinensiswere studied. The results showed that generat...The effects of different Cd (Cadmium) levels on generation of active oxygen speceies(AOS) and H2O2-scavenging system in the leaves of Brassica campestris L. ssp. chinensiswere studied. The results showed that generation rate, and H2O2 content were enhancedand malondialdehyde (MDA) content increased with the increase of Cd concentrations inthe growth medium. The activities of ascorbate peroxidase (APX), dehydroascorbatereductase (DR) and glutathione reductase (GR) were promoted by the addition of Cd.Exposed to Cd also increased the contents of ascorbate (AsA) and glutathione (GSH) in theleaves.展开更多
Toxic arsenic(As)and trace element selenium(Se)are transformed by microorganisms but their complex interactions in soil-plant systems have not been fully understood.An Asand Se-oxidizing bacterium,Agrobacterium sp.T3F...Toxic arsenic(As)and trace element selenium(Se)are transformed by microorganisms but their complex interactions in soil-plant systems have not been fully understood.An Asand Se-oxidizing bacterium,Agrobacterium sp.T3F4,was applied to a native seleniferous As-polluted soil to investigate As/Se uptake by the vegetable Brassica rapa L.and As-Se interaction as mediated by strain T3F4.The Se content in the aboveground plants was significantly enhanced by 34.1%,but the As content was significantly decreased by 20.5% in the T3F4-inoculated pot culture compared to the control(P<0.05).Similar result was shown in treatment with additional 5 mg/kg of Se(IV)in soil.In addition,the As contents in roots were significantly decreased by more than 35% under T3F4 or Se(IV)treatments(P<0.05).Analysis of As-Se-bacterium interaction in a soil simulation experiment showed that the bioavailability of Se significantly increased and As was immobilized with the addition of the T3F4strain(P<0.05).Furthermore,an As/Se co-exposure hydroponic experiment demonstrated that As uptake and accumulation in plants was reduced by increasing Se(IV)concentrations.The 50% growth inhibition concentration(IC50)values for As in plants were increased about one-fold and two-fold under co-exposure with 5 and 10μmol/L Se(IV),respectively.In conclusion,strain T3F4 improves Se uptake but decreases As uptake by plants via oxidation of As and Se,resulting in decrease of soil As bioavailability and As/Se competitive absorption by plants.This provides a potential bioremediation strategy for Se biofortification and As immobilization in As-polluted soil.展开更多
A field trial was conducted to evaluate the reduction of bioavailability of heavy metals including lead (Pb), zinc (Zn) and cadmium (Cd) in a soil contaminated by mining tailings in Shaoxing, Zhejiang, China. Three co...A field trial was conducted to evaluate the reduction of bioavailability of heavy metals including lead (Pb), zinc (Zn) and cadmium (Cd) in a soil contaminated by mining tailings in Shaoxing, Zhejiang, China. Three commercial phosphate (P) fertilizers including phosphate rock (PR), calcium magnesium phosphate (CMP), and single superphosphate (SSP) were applied to the plot at three P application rates, 50, 300, and 500 g/m2 with 9 treatments and control (CK). Plants, water soluble and exchangeable (WE) extra...展开更多
The influence of nitrification inhibitor(NI) 3,4 dimethylpyrazole phosphate(DMPP) on nitrate accumulation in greengrocery( Brassica campestris L. ssp. chinensis ) and vegetable soil at surface layer were investigated ...The influence of nitrification inhibitor(NI) 3,4 dimethylpyrazole phosphate(DMPP) on nitrate accumulation in greengrocery( Brassica campestris L. ssp. chinensis ) and vegetable soil at surface layer were investigated in field experiments in 2002 and 2003 Results showed that NI DMPP took no significant effect on yields of edible parts of greengrocery, but it could significantly decrease NO - 3 N concentration in greengrocery and in vegetable soil at surface layer. In addition, NI DMPP could reduce the NO - 3 N concentration during the prophase stage of storage.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
A genetic linkage map comprised of 131 loci was constructed with an F 2 population derived from an inter subspecific cross between Brassica campestris L. ssp. chinensis cv. 'aijiaohuang' and ssp. r...A genetic linkage map comprised of 131 loci was constructed with an F 2 population derived from an inter subspecific cross between Brassica campestris L. ssp. chinensis cv. 'aijiaohuang' and ssp. rapifera cv. 'qisihai'. The genetic map included 93 RAPD loci, 36 AFLP loci and 2 morphological loci organized into 10 main linkage groups (LGs) and 2 small groups, covering 1810.9cM with average distance between adjacent markers being approximately 13.8cM. The map is suitable for identification of molecular markers linked to important agronomic traits, QTL analysis, and even for marker assisted selection in breeding programs of Chinese cabbage and turnip.展开更多
To determine differential expression of genie male sterility A/B lines in Chinese cabbage-pak-choi (Brassica campestris ssp. chinensis Makino var. communis Tsen et Lee), we used the RNA fingerprinting technique, cDNA-...To determine differential expression of genie male sterility A/B lines in Chinese cabbage-pak-choi (Brassica campestris ssp. chinensis Makino var. communis Tsen et Lee), we used the RNA fingerprinting technique, cDNA-AFLP analysis, in different developmental stages and different tissues. While no obvious differential expressions were observed in rosette leaves, florescence leaves, and scapes, some differential expressions were found in alabstrums of A/B lines and among leaves, scapes and alabstrums. We analyzed the al-abstrums collected in different developmental stages with 10 primer combinations. We got a unique band between middle size alabstrums and large alabstrums in B line in one of the ten pair primers, and in another one pair, one band reflecting a higher gene-expression level in A line than that in B line was obtained. No unique bands were found with the other primer combinations. The bands reflecting different gene-expression level were confirmed by Northern hybridization. The results indicated that cDNA-AFLP was a suitable tool for studying differential expression of genie male sterility in plants. SDS-polyacrylamide gel electrophoresis patterns of soluble proteins further verified the difference in A/B lines.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
To assess the effects of N fertilizer ammonium sulphate nitrate [(NH4)2SO4 plus NH4NO3;ASN] with the new nitrification inhibitor (NI) 3, 4-dimethylpyrazole phosphate (DMPP)(ASN+DMPP) on yield, nitrate accumulation, an...To assess the effects of N fertilizer ammonium sulphate nitrate [(NH4)2SO4 plus NH4NO3;ASN] with the new nitrification inhibitor (NI) 3, 4-dimethylpyrazole phosphate (DMPP)(ASN+DMPP) on yield, nitrate accumulation, and quality of cabbage (Brassica campastrisL. ssp. pekinesis), two field trials were carried out under various soil-climaticconditions in Jinhua City and Xinchang County, Zhejiang Province of China in 2002.Results showed that DMPP could increase the mean yield by+2.0tha-1 in Jinhua, +5.5tha-1 inXinchang, decrease NO3--N content by -9.4% in Jinhua, -7.3% in Xinchang and improvenutritional quality by increasing vitamin C (VC), soluble sugar, K, Fe, Zn contentssignificantly.展开更多
Brassica campestris male fertility 19 (BcMF19; GenBank accession number GQ902048.1), a gene that is specially expressed in tapetum cells and microspores during anther development in B. campestris ssp. chinensis, whi...Brassica campestris male fertility 19 (BcMF19; GenBank accession number GQ902048.1), a gene that is specially expressed in tapetum cells and microspores during anther development in B. campestris ssp. chinensis, which is learned from the previous in situ hybridization study. In the present study, we constructed antisense-silenced plants of BcMF19 using B. campestris ssp. chinensis to validate this prediction. The morphology of the pistils, long anthers, and short anthers was significantly affected in 35sbcmf19 compared with the control samples. 4'-6-Diamidino-2-phenylindole staining revealed that two generative nuclei and one large vegetative nucleus were not affected in the mutant compared with control. Statistical analysis of Alexander's staining results showed that 96% of the control pollen grains had vitality, whereas only 86% of the mutant pollen grains did. Under scanning electron microscopy, the mutant demonstrated numerous abnormal pollen grains and resembled dried persimmon. The frequency of normal pollen grains was approximately 18%. Under transmission electron microscopy, the pollen intine during the binucleate and mature pollen stages in 35sbcmf19 exhibited abnormal thickening, especially at the germinal furrows, compared with control. In vitro pollen germination test showed that the tips of the mutant pollen tubes transformed into globular alveoli and stopped growing compared with control. On the other hand, in vivo pollen germination test suggested that BcMF19 affected the pollen tube extension in the pistil. These findings indicate that BcMF19 is essential to the pollen development and pollen tube extension orB. campestris ssp. chinensis.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 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A molecular genetic map of Chinese cabbage was constructed with a 102 recombinant inbred (RI) population from a cross of two cultivated Chinese cabbage lines 177 and 276, using AFLP and RAPD markers. 352 markers including 265 AFLP markers and 87 RAPD markers were integrated into 17 linkage groups. It covered a total of 2 665. 7 cM with an average interval of 7. 6 cM. AFLP marker is efficient for map construction while it easily forms clusters to cause big gaps in map. A total of 13.92 % abnormal segregation markers distributed in the map. The molecular genetic map is fundamental for gene localization, comparative genomics, and QTL mapping of important agronomic traits.
基金the National Natural Science Foundation of China(30671426)the Key Sci-Technology Project of Zhejiang Province,China(2005C12019-02)
文摘The study analyzed the silencing of BcMF12 gene regulated by BcA9 promoter in the transgenic pakchoi and confirmed the effect of antisense BcMF12 gene on the pollen development. A conserved BcMF12 gene fragment was amplified from the cDNA of flower buds in pakchoi (Brassica campestris L. ssp. chinensis, syn. B. rapa L. ssp. chinensis) and was fused to the anther specific BcA9 promoter. The plant antisense expression vector was constructed and then introduced into pakchoi via Agrobacterium-mediated transformation. The transgenic plants were screened by antibiotics and molecular analysis. PCR and Southern blot revealed that the antisense BcMF12-GUS fusion gene regulated by BcA9 promoter was integrated into transgenic plants. Northern blot suggested that the expression of BcMF12 gene was down-regulated significantly. The pollen germination rate of transgenic plants with antisense BcMF12 gene decreased as compared with that of the control plants. The expression of the gene BcMF12 related to the pollen development was inhibited by the antisense BcMF12 driven by BcA9 promoter, which consequently affected the pollen development in pakchoi.
文摘We conducted plant growth experiments in microbe-free vermiculite to study the effects of four types of fermented seaweed liquid fertilizer (SLF) made from nori (Pyropia yezoensis) seaweed on the germination, plant growth characteristics, SPAD value, and nutrient content and uptake of komatsuna (Brassica rapa L. var. wakana komatsuna). The four types of fermented nori SLF used in this study were prepared by anaerobic fermentation of unwashed nori (SLF1), aerobic fermentation of unwashed nori (SLF2), anaerobic fermentation of washed nori (SLF3), and aerobic fermentation of washed nori (SLF4). Komatsuna seeds treated with 200-, 300-, and 400-fold dilutions of SLFs exhibited improved relative germination ratios (RGRs) at 3 and 4 days after sowing (DAS). At 4 DAS, the RGRs of seeds treated with 10-, 100-, 200-, 300-, and 400-fold SLF dilutions showed no differential effect. Seeds treated with undiluted SLFs did not germinate by 4 DAS. SLF1 may promote komatsuna seed germination. The nitrogen (N), calcium, magnesium, sodium (Na), and iodine (I) contents of plants treated with SLF1 were significantly increased relative to plants treated with the other SLFs. Moreover, the I and Na contents of plants were significantly increased by foliar spray application of different dilutions of SLF1. However, SLF treatment markedly reduced the shoot dry weight compared with 1/2-strength modified Hoagland nutrient (MHN) solution, although the same amounts of N and K were applied. SPAD values of the plants treated with SLFs were significantly higher than those of plants treated with MHN. Foliar treatment with SLFs had no significant effect on plant growth, SPAD value, or uptake of nutrients (except Na) relative to the control, but the I content was increased. Plants treated with SLF1 and SLF2 exhibited the highest Na uptake. Foliar spray treatments with SLF1 resulted in the highest I contents in plants. Based on our results, SLF1 is suitable for use as a liquid fertilizer to promote germination and increase nutrient content in komatsuna. These results need to be followed up in soil experiments in the presence of microbes in the rhizosphere.
文摘The effects of different Cd (Cadmium) levels on generation of active oxygen speceies(AOS) and H2O2-scavenging system in the leaves of Brassica campestris L. ssp. chinensiswere studied. The results showed that generation rate, and H2O2 content were enhancedand malondialdehyde (MDA) content increased with the increase of Cd concentrations inthe growth medium. The activities of ascorbate peroxidase (APX), dehydroascorbatereductase (DR) and glutathione reductase (GR) were promoted by the addition of Cd.Exposed to Cd also increased the contents of ascorbate (AsA) and glutathione (GSH) in theleaves.
基金supported by the National Natural Science Foundation of China(No.41771283)"Longyun Program"of the College of Life Science and Technology of Huazhong Agricultural University。
文摘Toxic arsenic(As)and trace element selenium(Se)are transformed by microorganisms but their complex interactions in soil-plant systems have not been fully understood.An Asand Se-oxidizing bacterium,Agrobacterium sp.T3F4,was applied to a native seleniferous As-polluted soil to investigate As/Se uptake by the vegetable Brassica rapa L.and As-Se interaction as mediated by strain T3F4.The Se content in the aboveground plants was significantly enhanced by 34.1%,but the As content was significantly decreased by 20.5% in the T3F4-inoculated pot culture compared to the control(P<0.05).Similar result was shown in treatment with additional 5 mg/kg of Se(IV)in soil.In addition,the As contents in roots were significantly decreased by more than 35% under T3F4 or Se(IV)treatments(P<0.05).Analysis of As-Se-bacterium interaction in a soil simulation experiment showed that the bioavailability of Se significantly increased and As was immobilized with the addition of the T3F4strain(P<0.05).Furthermore,an As/Se co-exposure hydroponic experiment demonstrated that As uptake and accumulation in plants was reduced by increasing Se(IV)concentrations.The 50% growth inhibition concentration(IC50)values for As in plants were increased about one-fold and two-fold under co-exposure with 5 and 10μmol/L Se(IV),respectively.In conclusion,strain T3F4 improves Se uptake but decreases As uptake by plants via oxidation of As and Se,resulting in decrease of soil As bioavailability and As/Se competitive absorption by plants.This provides a potential bioremediation strategy for Se biofortification and As immobilization in As-polluted soil.
基金the National Natural Sci-ence Foundation of China (No. 40771100, 40432004)
文摘A field trial was conducted to evaluate the reduction of bioavailability of heavy metals including lead (Pb), zinc (Zn) and cadmium (Cd) in a soil contaminated by mining tailings in Shaoxing, Zhejiang, China. Three commercial phosphate (P) fertilizers including phosphate rock (PR), calcium magnesium phosphate (CMP), and single superphosphate (SSP) were applied to the plot at three P application rates, 50, 300, and 500 g/m2 with 9 treatments and control (CK). Plants, water soluble and exchangeable (WE) extra...
文摘The influence of nitrification inhibitor(NI) 3,4 dimethylpyrazole phosphate(DMPP) on nitrate accumulation in greengrocery( Brassica campestris L. ssp. chinensis ) and vegetable soil at surface layer were investigated in field experiments in 2002 and 2003 Results showed that NI DMPP took no significant effect on yields of edible parts of greengrocery, but it could significantly decrease NO - 3 N concentration in greengrocery and in vegetable soil at surface layer. In addition, NI DMPP could reduce the NO - 3 N concentration during the prophase stage of storage.
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.
文摘A genetic linkage map comprised of 131 loci was constructed with an F 2 population derived from an inter subspecific cross between Brassica campestris L. ssp. chinensis cv. 'aijiaohuang' and ssp. rapifera cv. 'qisihai'. The genetic map included 93 RAPD loci, 36 AFLP loci and 2 morphological loci organized into 10 main linkage groups (LGs) and 2 small groups, covering 1810.9cM with average distance between adjacent markers being approximately 13.8cM. The map is suitable for identification of molecular markers linked to important agronomic traits, QTL analysis, and even for marker assisted selection in breeding programs of Chinese cabbage and turnip.
基金supported by the National Natural Science Foundation of China(39670512)
文摘To determine differential expression of genie male sterility A/B lines in Chinese cabbage-pak-choi (Brassica campestris ssp. chinensis Makino var. communis Tsen et Lee), we used the RNA fingerprinting technique, cDNA-AFLP analysis, in different developmental stages and different tissues. While no obvious differential expressions were observed in rosette leaves, florescence leaves, and scapes, some differential expressions were found in alabstrums of A/B lines and among leaves, scapes and alabstrums. We analyzed the al-abstrums collected in different developmental stages with 10 primer combinations. We got a unique band between middle size alabstrums and large alabstrums in B line in one of the ten pair primers, and in another one pair, one band reflecting a higher gene-expression level in A line than that in B line was obtained. No unique bands were found with the other primer combinations. The bands reflecting different gene-expression level were confirmed by Northern hybridization. The results indicated that cDNA-AFLP was a suitable tool for studying differential expression of genie male sterility in plants. SDS-polyacrylamide gel electrophoresis patterns of soluble proteins further verified the difference in A/B lines.
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 the National Natural Science Foundation of China(30370838)Science and Technology Committee of Zhejiang Province,China(021102084)BASF Company of Germany.
文摘To assess the effects of N fertilizer ammonium sulphate nitrate [(NH4)2SO4 plus NH4NO3;ASN] with the new nitrification inhibitor (NI) 3, 4-dimethylpyrazole phosphate (DMPP)(ASN+DMPP) on yield, nitrate accumulation, and quality of cabbage (Brassica campastrisL. ssp. pekinesis), two field trials were carried out under various soil-climaticconditions in Jinhua City and Xinchang County, Zhejiang Province of China in 2002.Results showed that DMPP could increase the mean yield by+2.0tha-1 in Jinhua, +5.5tha-1 inXinchang, decrease NO3--N content by -9.4% in Jinhua, -7.3% in Xinchang and improvenutritional quality by increasing vitamin C (VC), soluble sugar, K, Fe, Zn contentssignificantly.
基金supported by the National Basic Research Program of China (2012CB113900)the National Natural Science Foundation of China (31071805)the Key Sci-Technology Project of Zhejiang Province, China (2010C12004)
文摘Brassica campestris male fertility 19 (BcMF19; GenBank accession number GQ902048.1), a gene that is specially expressed in tapetum cells and microspores during anther development in B. campestris ssp. chinensis, which is learned from the previous in situ hybridization study. In the present study, we constructed antisense-silenced plants of BcMF19 using B. campestris ssp. chinensis to validate this prediction. The morphology of the pistils, long anthers, and short anthers was significantly affected in 35sbcmf19 compared with the control samples. 4'-6-Diamidino-2-phenylindole staining revealed that two generative nuclei and one large vegetative nucleus were not affected in the mutant compared with control. Statistical analysis of Alexander's staining results showed that 96% of the control pollen grains had vitality, whereas only 86% of the mutant pollen grains did. Under scanning electron microscopy, the mutant demonstrated numerous abnormal pollen grains and resembled dried persimmon. The frequency of normal pollen grains was approximately 18%. Under transmission electron microscopy, the pollen intine during the binucleate and mature pollen stages in 35sbcmf19 exhibited abnormal thickening, especially at the germinal furrows, compared with control. In vitro pollen germination test showed that the tips of the mutant pollen tubes transformed into globular alveoli and stopped growing compared with control. On the other hand, in vivo pollen germination test suggested that BcMF19 affected the pollen tube extension in the pistil. These findings indicate that BcMF19 is essential to the pollen development and pollen tube extension orB. campestris ssp. chinensis.
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.