2016 Vol. 31, No. 4
Display Method:
2016, 31(4): 377-383.
doi: 10.19303/j.issn.1008-0384.2016.04.009
Abstract:
The diamondback moth (DBM), Plutella xylostella (L.) is a key insect pest on cruciferous plants all over the world. Olfactory perception is critical for survival and reproduction in insects, and correspondingly provides a new target to control DBM. Hereby, an odorant binding protein (OBP) gene from P.xylostella,PxylOBP13 (GenBank accession number:KT156679) was cloned; the bio-information characteristics were analyzed; and a phylogenetic tree was constructed. The results showed that the full-length of open reading frame of PxylOBP13 is 387 bp and encodes 128 amino acids; PxylOBP13 contains 6 conserved cysteine residues and the conserved domain of odorant binding protein family, and 3 hydrophobic regions which are potential binding sites for hydrophobic odorants. The protein molecular mass was predicted as 14.33 kDa with an isoelectric point of 7.55, but the N-terminal without signal peptide; the similarity of sequence between PxylOBP13 and six lepidopteran insects can reach above 50%. The results can provide theoretical support for further research on the function of OBPs in DBM and development of effective management of DBM based on olfactory mechanism.
The diamondback moth (DBM), Plutella xylostella (L.) is a key insect pest on cruciferous plants all over the world. Olfactory perception is critical for survival and reproduction in insects, and correspondingly provides a new target to control DBM. Hereby, an odorant binding protein (OBP) gene from P.xylostella,PxylOBP13 (GenBank accession number:KT156679) was cloned; the bio-information characteristics were analyzed; and a phylogenetic tree was constructed. The results showed that the full-length of open reading frame of PxylOBP13 is 387 bp and encodes 128 amino acids; PxylOBP13 contains 6 conserved cysteine residues and the conserved domain of odorant binding protein family, and 3 hydrophobic regions which are potential binding sites for hydrophobic odorants. The protein molecular mass was predicted as 14.33 kDa with an isoelectric point of 7.55, but the N-terminal without signal peptide; the similarity of sequence between PxylOBP13 and six lepidopteran insects can reach above 50%. The results can provide theoretical support for further research on the function of OBPs in DBM and development of effective management of DBM based on olfactory mechanism.
2016, 31(4): 384-388.
doi: 10.19303/j.issn.1008-0384.2016.04.010
Abstract:
Bacillus subtilis XF-1 inhibits the growth of many plant pathogens, and therefore, is an important agricultural biocontrol agent. The gene sequence of 3 853 proteins was analyzed to identify the segments responsible for the generation of proteins secreted by the bacterium. The prediction algorithm base on the genetic information applied SignalP, ProtComp, TMHMM, Phobius, LipoP and TatP. The distribution of amino acids, length of signal peptide, and cleavage site of the 104 secretory proteins found in XF-1 were determined. The lengths of amino acid sequence and signal peptide of XF-1 differed from those of the pathogens. But, its cleavage site of the signal peptide belonged to the same AXA type as those of the pathogenic fungi, bacteria and oomycete found on plants. The bioinformatics analyses carried out in this study successfully forecasted the secretory proteins from B. subtilis. And, the identical type of cleavage site of signal peptide between SF-1 and other microorganisms suggested that the site was genetically conservative.
Bacillus subtilis XF-1 inhibits the growth of many plant pathogens, and therefore, is an important agricultural biocontrol agent. The gene sequence of 3 853 proteins was analyzed to identify the segments responsible for the generation of proteins secreted by the bacterium. The prediction algorithm base on the genetic information applied SignalP, ProtComp, TMHMM, Phobius, LipoP and TatP. The distribution of amino acids, length of signal peptide, and cleavage site of the 104 secretory proteins found in XF-1 were determined. The lengths of amino acid sequence and signal peptide of XF-1 differed from those of the pathogens. But, its cleavage site of the signal peptide belonged to the same AXA type as those of the pathogenic fungi, bacteria and oomycete found on plants. The bioinformatics analyses carried out in this study successfully forecasted the secretory proteins from B. subtilis. And, the identical type of cleavage site of signal peptide between SF-1 and other microorganisms suggested that the site was genetically conservative.
2016, 31(4): 389-394.
doi: 10.19303/j.issn.1008-0384.2016.04.011
Abstract:
Endophytic fungi antagonistic against the selected bacteria and phytopathogens were first screened from the microbial samples collected from the single-clump tea plants using the double-plate and the flat-stand methods. Then, they were identified by their morphologies and 18SrDNA sequences. Three strains of the fungi, i.e., F15GEN, F15Ye, and LB35JING, were isolated. The diameter of the inhibition zone of F15GEN against Staphylococcus aureus was 13.36 mm, and that of F15YE against Bacillus subtilis 14.92 mm. In addition, LB35JING and F15GEN showed inhibition activities against Rhizoctonia solani and Valsa ambiens Pers, F15YE against Sphaerulina juglandis, and LB35JING against Fusarium. The 18S rDNA sequence of F15GEN identified it as Penicillium decumbens, while those of F15YE and LB35JING linked them to Penicillium sp.
Endophytic fungi antagonistic against the selected bacteria and phytopathogens were first screened from the microbial samples collected from the single-clump tea plants using the double-plate and the flat-stand methods. Then, they were identified by their morphologies and 18SrDNA sequences. Three strains of the fungi, i.e., F15GEN, F15Ye, and LB35JING, were isolated. The diameter of the inhibition zone of F15GEN against Staphylococcus aureus was 13.36 mm, and that of F15YE against Bacillus subtilis 14.92 mm. In addition, LB35JING and F15GEN showed inhibition activities against Rhizoctonia solani and Valsa ambiens Pers, F15YE against Sphaerulina juglandis, and LB35JING against Fusarium. The 18S rDNA sequence of F15GEN identified it as Penicillium decumbens, while those of F15YE and LB35JING linked them to Penicillium sp.
2016, 31(4): 395-400.
doi: 10.19303/j.issn.1008-0384.2016.04.012
Abstract:
Risk evaluation and source tracing on the environmental pollution from heavy metal contamination in soil at tea plantations in Wuyishan were conducted. Contents of 8 major heavy metals in the soil samples were analyzed using multivariate statistics, evaluated according to the Hakanson potential ecological risk assessment index, and traced to their origins by a principal component analysis. The results indicated that (1) the average concentrations of Pb, Cd, and Hg were 2.2, 3.6, and 2.6 times, respectively, higher than the respective reference values for Fujian standards on these elements, while, although less severe, those of Cu, Zn, Ni, Cr, and Pb also apparently showed their presences in the surface soils; (2) using the potential ecological risk assessment index, the risk levels of Cd and Hg were categorized as medium and moderately heavy, those of Cu, Zn, Pb, Cr, Ni and As graded as low, and overall, the soils at the plantations were under medium and heavy levels (78.9%); and, (3) the principal component analysis suggested that the main source of Pb contamination stemmed from traffic pollution, those of Cu, Cr, and Ni from the natural components in soil at the sites, that of Hg from agricultural sources, that of Zn from natural, geological background and/or traffic at the surrounding areas, and, that of Cd from transportation and/or agricultural origins. Consequently, special attention must be paid on Cd and Hg as they also inherently post greater risks than others on human health.
Risk evaluation and source tracing on the environmental pollution from heavy metal contamination in soil at tea plantations in Wuyishan were conducted. Contents of 8 major heavy metals in the soil samples were analyzed using multivariate statistics, evaluated according to the Hakanson potential ecological risk assessment index, and traced to their origins by a principal component analysis. The results indicated that (1) the average concentrations of Pb, Cd, and Hg were 2.2, 3.6, and 2.6 times, respectively, higher than the respective reference values for Fujian standards on these elements, while, although less severe, those of Cu, Zn, Ni, Cr, and Pb also apparently showed their presences in the surface soils; (2) using the potential ecological risk assessment index, the risk levels of Cd and Hg were categorized as medium and moderately heavy, those of Cu, Zn, Pb, Cr, Ni and As graded as low, and overall, the soils at the plantations were under medium and heavy levels (78.9%); and, (3) the principal component analysis suggested that the main source of Pb contamination stemmed from traffic pollution, those of Cu, Cr, and Ni from the natural components in soil at the sites, that of Hg from agricultural sources, that of Zn from natural, geological background and/or traffic at the surrounding areas, and, that of Cd from transportation and/or agricultural origins. Consequently, special attention must be paid on Cd and Hg as they also inherently post greater risks than others on human health.
2016, 31(4): 401-407.
doi: 10.19303/j.issn.1008-0384.2016.04.013
Abstract:
The concentration and distribution of Selenium (Se) in the soils in the city of Guangzhou, as well as the factors affecting them were investigated. Se content in soil samples collected from areas in the city was determined by the hydride generation atomic absorption spectrometry. The results indicated that Se was higher in the surface layer of the soil. The total Se in soil ranged from 0.02 mgkg-1 to 2.87 mgkg-1 with a GM of 0.314mgkg-1, and the available Se from 1.01 gkg-1 to 115.01 gkg-1 with a GM of 19.879gkg-1. A significant variation on the levels of Se contamination in the municipal areas was observed. The more highly contaminated regions included the eastern part of south Nansha District, Panyu District, and Zengcheng District. The soil Se concentration and distribution appeared to be affected greatly by the type and properties of the soil. Under the acidic condition, the sandy clay and granite soil rich in organic matters tended to have high concentrations of Se. It appeared that pH, organic matters, and CEC all contributed to the variation on the concentration and distribution of Se in the soil throughout the city.
The concentration and distribution of Selenium (Se) in the soils in the city of Guangzhou, as well as the factors affecting them were investigated. Se content in soil samples collected from areas in the city was determined by the hydride generation atomic absorption spectrometry. The results indicated that Se was higher in the surface layer of the soil. The total Se in soil ranged from 0.02 mgkg-1 to 2.87 mgkg-1 with a GM of 0.314mgkg-1, and the available Se from 1.01 gkg-1 to 115.01 gkg-1 with a GM of 19.879gkg-1. A significant variation on the levels of Se contamination in the municipal areas was observed. The more highly contaminated regions included the eastern part of south Nansha District, Panyu District, and Zengcheng District. The soil Se concentration and distribution appeared to be affected greatly by the type and properties of the soil. Under the acidic condition, the sandy clay and granite soil rich in organic matters tended to have high concentrations of Se. It appeared that pH, organic matters, and CEC all contributed to the variation on the concentration and distribution of Se in the soil throughout the city.
2016, 31(4): 408-414.
doi: 10.19303/j.issn.1008-0384.2016.04.014
Abstract:
By using the waste from tree-pruning in Fuzhou and adjusting the C/N ratio with chicken manure for composting, the resulting composts were evaluated as a potential substrate for plant growth. During the composting, a real-time monitoring on the aerobic fermentation was conducted to understand the changes in the nutrient content of the compost and their effect on the growth of the model plant, Ruellia brittoniana. A continual decline on the organic matters accompanied by an increase on the contents of nitrogen, phosphorus, potassium, and other nutrients in the compost was observed. On the 10th day of composting, the compost reached a constant internal temperature of 50℃, while its pH decreased gradually after an initial increase and stabilized after the 35th day. The moisture content of the compost decreased continuously throughout the process. The C/N ratio of the compost arrived at the fully decomposed stage (i.e., 15-20/1) on the 35th day. The height, leaf area, and dry biomass of the plants grown on the soil/compost mixtures were found superior to those on soil alone. When one part of soil was mixed with two parts of the compost, the nutrient content in the above-ground, as well as under-ground, parts of the plant was at its maximum. It was concluded that when the temperature was 45-49℃ (averaging 48℃), C/N at 19.50, and pH at 9, the compost was considered fully decomposed with the total nitrogen, phosphorus, and potassium contents of 1.28%, 1.73%, and 1.95%, respectively. And, on substrate with a mixing ratio of two parts compost to one part soil, the best result was obtained for the growth of R. brittoniana. It was expected that a compost could be generated from tree-pruning waste in the city to satisfactorily enrich the soil for municipal landscaping on viaducts.
By using the waste from tree-pruning in Fuzhou and adjusting the C/N ratio with chicken manure for composting, the resulting composts were evaluated as a potential substrate for plant growth. During the composting, a real-time monitoring on the aerobic fermentation was conducted to understand the changes in the nutrient content of the compost and their effect on the growth of the model plant, Ruellia brittoniana. A continual decline on the organic matters accompanied by an increase on the contents of nitrogen, phosphorus, potassium, and other nutrients in the compost was observed. On the 10th day of composting, the compost reached a constant internal temperature of 50℃, while its pH decreased gradually after an initial increase and stabilized after the 35th day. The moisture content of the compost decreased continuously throughout the process. The C/N ratio of the compost arrived at the fully decomposed stage (i.e., 15-20/1) on the 35th day. The height, leaf area, and dry biomass of the plants grown on the soil/compost mixtures were found superior to those on soil alone. When one part of soil was mixed with two parts of the compost, the nutrient content in the above-ground, as well as under-ground, parts of the plant was at its maximum. It was concluded that when the temperature was 45-49℃ (averaging 48℃), C/N at 19.50, and pH at 9, the compost was considered fully decomposed with the total nitrogen, phosphorus, and potassium contents of 1.28%, 1.73%, and 1.95%, respectively. And, on substrate with a mixing ratio of two parts compost to one part soil, the best result was obtained for the growth of R. brittoniana. It was expected that a compost could be generated from tree-pruning waste in the city to satisfactorily enrich the soil for municipal landscaping on viaducts.
2016, 31(4): 415-418.
doi: 10.19303/j.issn.1008-0384.2016.04.015
Abstract:
Biodegradation by Trichoderma pleuroticola T9 on lignite from Shanxi province was studied aiming to optimize the process in regard to the particle size and slurry concentration of the coal, as well as the inoculum quantity and fermentation time. The results indicated that the biodegradation was affected in the order of particle size inoculum quantity concentration of coal slurry duration of fermentation. The optimized conditions to achieve the maximum degrading rate of 60% were determined to be (a) a use of lignite with a particle size of 0.1 mm, (b) a coal slurry concentration of 2%, (c) the inoculation of 10 mL of T. pleuroticola T9 fermentation broth, and (d) incubation for 14 d.
Biodegradation by Trichoderma pleuroticola T9 on lignite from Shanxi province was studied aiming to optimize the process in regard to the particle size and slurry concentration of the coal, as well as the inoculum quantity and fermentation time. The results indicated that the biodegradation was affected in the order of particle size inoculum quantity concentration of coal slurry duration of fermentation. The optimized conditions to achieve the maximum degrading rate of 60% were determined to be (a) a use of lignite with a particle size of 0.1 mm, (b) a coal slurry concentration of 2%, (c) the inoculation of 10 mL of T. pleuroticola T9 fermentation broth, and (d) incubation for 14 d.
2016, 31(4): 419-423.
doi: 10.19303/j.issn.1008-0384.2016.04.016
Abstract:
Dark brow soil at the apple-pear orchards at Yanji in the Korean Autonomous Prefecture of Yanbian in Jilin province was sampled for the experimentation on organic phosphorus fractionation. The process was optimized by using the Bowman-Cole method modified by Xiong Heng-duo and Fan Ye-kuan. The fractionation included the following major steps:(1) to the acidic soil pretreated with chloroform, 0.5 molL-1 of NaHCO3 were added with ultrasonic treatment for 10 minutes followed by oscillation for 30 minutes to extract the labile organic phosphorus into the supernatant; (2) to the soil left after the initial extraction, 0.1 molL-1 of NaOH was added with ultrasound for 10 minutes followed by oscillating for 4 hours to leach the stable and the moderately labile organic phosphorus fractions into the alkali solution; (3) to the above alkali supernatant, acid was added to adjust the pH to 3.00 to precipitate the highly stable organic phosphorus and allow the moderately stable fraction remain in the solution; and finally, (4) to the soil, 1 molL-1 of H2SO4 was added with a constant oscillation for 3 hours to extract the moderately labile organic phosphorus. In comparison to the existing methods, the current fractionation process on the acidic orchard soil in north China appeared to have optimized the conditions with improved efficiency.
Dark brow soil at the apple-pear orchards at Yanji in the Korean Autonomous Prefecture of Yanbian in Jilin province was sampled for the experimentation on organic phosphorus fractionation. The process was optimized by using the Bowman-Cole method modified by Xiong Heng-duo and Fan Ye-kuan. The fractionation included the following major steps:(1) to the acidic soil pretreated with chloroform, 0.5 molL-1 of NaHCO3 were added with ultrasonic treatment for 10 minutes followed by oscillation for 30 minutes to extract the labile organic phosphorus into the supernatant; (2) to the soil left after the initial extraction, 0.1 molL-1 of NaOH was added with ultrasound for 10 minutes followed by oscillating for 4 hours to leach the stable and the moderately labile organic phosphorus fractions into the alkali solution; (3) to the above alkali supernatant, acid was added to adjust the pH to 3.00 to precipitate the highly stable organic phosphorus and allow the moderately stable fraction remain in the solution; and finally, (4) to the soil, 1 molL-1 of H2SO4 was added with a constant oscillation for 3 hours to extract the moderately labile organic phosphorus. In comparison to the existing methods, the current fractionation process on the acidic orchard soil in north China appeared to have optimized the conditions with improved efficiency.
2016, 31(4): 424-430.
doi: 10.19303/j.issn.1008-0384.2016.04.017
Abstract:
The Monascus strain, L03, was isolated from the red kojic rice samples collected from Yongchun, Anxi, Gutian, Nanping, Sanming, and Longyan in Fujian for its high red-pigment-producing ability. Based on the morphology and molecular biology of L03, it was identified to be M. purpureus. Subsequently, single factor and orthogonal experiments were conducted to optimize the conditions for the liquid fermentation of the yeast. Color of the fermented suspension reached 1,578 U/mL when the yeast was inoculated 6% by weight into a liquid medium consisting of 8% of glycerol, 1.5% of peptone, 0.1% of Mg2SO4, and 0.25% of KH2PO4 in a loading volume of 100 mL/250 mL and incubated at 32℃ with constant agitation at the speed of 180 rpm for 9 days.
The Monascus strain, L03, was isolated from the red kojic rice samples collected from Yongchun, Anxi, Gutian, Nanping, Sanming, and Longyan in Fujian for its high red-pigment-producing ability. Based on the morphology and molecular biology of L03, it was identified to be M. purpureus. Subsequently, single factor and orthogonal experiments were conducted to optimize the conditions for the liquid fermentation of the yeast. Color of the fermented suspension reached 1,578 U/mL when the yeast was inoculated 6% by weight into a liquid medium consisting of 8% of glycerol, 1.5% of peptone, 0.1% of Mg2SO4, and 0.25% of KH2PO4 in a loading volume of 100 mL/250 mL and incubated at 32℃ with constant agitation at the speed of 180 rpm for 9 days.
2016, 31(4): 431-436.
doi: 10.19303/j.issn.1008-0384.2016.04.018
Abstract:
Effect of various factors in an ultrasound-assisted process on the polysaccharide extraction from Polygonatum filipes were studied for the technology optimization. The liquid/material ratio, temperature, as well as power and duration of ultrasonic application for the process were scrutinized. A quadratic regression rotational combinational design and the Design Expert 7.0 analytical procedures were applied to establish a regression model for projecting the maximal extraction yield under optimized conditions. Theoretically, the optimized process included the application of a liquid/material ratio of 17.81 mL/1 g at 72.97℃ with a 152.85 W ultrasonic treatment for 59.74 min to reach 16.6471% yield on polysaccharides. In a triplicated test run, an averaged polysaccharide yield of 16.59% was obtained with a liquid/material ratio of 18 mL/1 g at 73℃ with a 150 W ultrasonic treatment for 60 min. The result showed that the mathematic model was accurate in predicting the performance of the extraction process.
Effect of various factors in an ultrasound-assisted process on the polysaccharide extraction from Polygonatum filipes were studied for the technology optimization. The liquid/material ratio, temperature, as well as power and duration of ultrasonic application for the process were scrutinized. A quadratic regression rotational combinational design and the Design Expert 7.0 analytical procedures were applied to establish a regression model for projecting the maximal extraction yield under optimized conditions. Theoretically, the optimized process included the application of a liquid/material ratio of 17.81 mL/1 g at 72.97℃ with a 152.85 W ultrasonic treatment for 59.74 min to reach 16.6471% yield on polysaccharides. In a triplicated test run, an averaged polysaccharide yield of 16.59% was obtained with a liquid/material ratio of 18 mL/1 g at 73℃ with a 150 W ultrasonic treatment for 60 min. The result showed that the mathematic model was accurate in predicting the performance of the extraction process.
2016, 31(4): 437-443.
doi: 10.19303/j.issn.1008-0384.2016.04.019
Abstract:
Deterioration and viability loss of rice grains during storage could greatly affect the national food security and rice breeding. Thus, prolonging the shelf life of rice is of significant interest for the farmers and the researchers. This article reviews the relationship between the seed vigor and shelf life, as well as the current progress in the field of study from three aspects,i.e., the lipid metabolism and oxidation, oxidative stress and antioxidant system, and the plant repair mechanisms. The defi ciencies in the existing studies are discussed. The protective and repair mechanisms of the plants are specifically elaborated as they were considered critical in better understanding the seed deterioration and in providing guidelines for the breeding of rice varieties with desirable shelf life.
Deterioration and viability loss of rice grains during storage could greatly affect the national food security and rice breeding. Thus, prolonging the shelf life of rice is of significant interest for the farmers and the researchers. This article reviews the relationship between the seed vigor and shelf life, as well as the current progress in the field of study from three aspects,i.e., the lipid metabolism and oxidation, oxidative stress and antioxidant system, and the plant repair mechanisms. The defi ciencies in the existing studies are discussed. The protective and repair mechanisms of the plants are specifically elaborated as they were considered critical in better understanding the seed deterioration and in providing guidelines for the breeding of rice varieties with desirable shelf life.
