2017 Vol. 32, No. 1
Display Method:
2017, 32(1): 1-6.
doi: 10.19303/j.issn.1008-0384.2017.01.001
Abstract:
Widely exists in water and soil, Aeromonas hydrophila is a commonpathogen for human, livestock and fish. It was previously observed in our lab that the expression of the proteins associated with the fatty acid biosynthesis in A. hydrophilarose under the stress of chlortetracycline. But the specific properties and functions were not understood. Therefore, this study was designed to clone and express those potentially important proteins, including acetyl-coenzyme A carboxylase carboxyl transferase subunit alpha (AccA), acetyl-coenzyme A carboxylase carboxyl transferase subunit beta (AccD), 3-oxoacyl-[acyl-carrier-protein] synthase Ⅰ (FabB), and malonyl coA-acyl carrier protein transacylase (FabD) for further investigation. By comparing the survival rates of high-expression strains of A. hydrophila under chlortetracycline stress, the drug-resistance relating to the proteinsin the fatty acid biosynthesispathway was analyzed. The results showed that the high-expression proteins, AccD, FabB and FabD, could indeed significantly increase the survival rate of the pathogen under chlortetracycline stress, while AccA did so only during the initial stage. Consequently, a critical role of these proteins involving the bacterial drug-resistance was clearly demonstrated. With the finding, further study to unveil the mechanism of antibiotic-resistance of the pathogen is in order.
Widely exists in water and soil, Aeromonas hydrophila is a commonpathogen for human, livestock and fish. It was previously observed in our lab that the expression of the proteins associated with the fatty acid biosynthesis in A. hydrophilarose under the stress of chlortetracycline. But the specific properties and functions were not understood. Therefore, this study was designed to clone and express those potentially important proteins, including acetyl-coenzyme A carboxylase carboxyl transferase subunit alpha (AccA), acetyl-coenzyme A carboxylase carboxyl transferase subunit beta (AccD), 3-oxoacyl-[acyl-carrier-protein] synthase Ⅰ (FabB), and malonyl coA-acyl carrier protein transacylase (FabD) for further investigation. By comparing the survival rates of high-expression strains of A. hydrophila under chlortetracycline stress, the drug-resistance relating to the proteinsin the fatty acid biosynthesispathway was analyzed. The results showed that the high-expression proteins, AccD, FabB and FabD, could indeed significantly increase the survival rate of the pathogen under chlortetracycline stress, while AccA did so only during the initial stage. Consequently, a critical role of these proteins involving the bacterial drug-resistance was clearly demonstrated. With the finding, further study to unveil the mechanism of antibiotic-resistance of the pathogen is in order.
2017, 32(1): 7-11.
doi: 10.19303/j.issn.1008-0384.2017.01.002
Abstract:
Based upon the characterization of gB gene retrieved from GenBank, specific primers were selected to amplify the gB gene of porcine cytomegalovirus (PCMV) FJ01 isolated in Fujian. The target PCR fragments were then cloned and sequenced. The gB gene was found to have 2 580 nucleotides, encoding 859 amino acids. Its homologies on nucleotide and amino acid sequences with the data at GenBank were greater than 98.3% and 97.9%, respectively. In addition, nearly half of the PCMV isolates had a same ACA nucleotide deletion in their gB genes that correlated to the phylogenetic evolution of the isolates, except ZZ strain.
Based upon the characterization of gB gene retrieved from GenBank, specific primers were selected to amplify the gB gene of porcine cytomegalovirus (PCMV) FJ01 isolated in Fujian. The target PCR fragments were then cloned and sequenced. The gB gene was found to have 2 580 nucleotides, encoding 859 amino acids. Its homologies on nucleotide and amino acid sequences with the data at GenBank were greater than 98.3% and 97.9%, respectively. In addition, nearly half of the PCMV isolates had a same ACA nucleotide deletion in their gB genes that correlated to the phylogenetic evolution of the isolates, except ZZ strain.
2017, 32(1): 12-16.
doi: 10.19303/j.issn.1008-0384.2017.01.003
Abstract:
The molecular epidemiology on the mycoplasma pneumonia of sheep and the contagious caprine pleuropneumonia of goats in Fujian were investigated. A total of 61 samples from the goats with suspected infection of the diseases were collected from 6 regions in the province during 2014-2016. PCR with the mycoplasmatales primer as well as the specific primers for Mycoplasma ovipneumoniae, Mycoplasma mycoides subsp.capri, Mycoplasma capricolum Subsp. Capripneumonia, Mycoplasma capricolum subsp.capri, Mycoplasma arginin, Acholeplasma laidlawii and Mycoplasma agalactiae were applied for the detection.Part of the PCR positive clinical samples were selected to isolate Mycoplasma for subsequent cloning and sequencing based on their 16S rRNA. The detection rates on M. ovipneumoniae, M. mycoides subsp.capri, A. laidlawii and M. arginine were 73.77%(45/61), 6.56%(4/61), 6.56%(4/61) and 3.28%(2/61), respectively. The results suggested that the suspected contagious caprine pleuropneumonia in the province were mycoplasma pneumonia of sheep and goats caused mainly by M.ovipneumoniae. The finding would lead to effective prevention and treatment measures for the diseases.
The molecular epidemiology on the mycoplasma pneumonia of sheep and the contagious caprine pleuropneumonia of goats in Fujian were investigated. A total of 61 samples from the goats with suspected infection of the diseases were collected from 6 regions in the province during 2014-2016. PCR with the mycoplasmatales primer as well as the specific primers for Mycoplasma ovipneumoniae, Mycoplasma mycoides subsp.capri, Mycoplasma capricolum Subsp. Capripneumonia, Mycoplasma capricolum subsp.capri, Mycoplasma arginin, Acholeplasma laidlawii and Mycoplasma agalactiae were applied for the detection.Part of the PCR positive clinical samples were selected to isolate Mycoplasma for subsequent cloning and sequencing based on their 16S rRNA. The detection rates on M. ovipneumoniae, M. mycoides subsp.capri, A. laidlawii and M. arginine were 73.77%(45/61), 6.56%(4/61), 6.56%(4/61) and 3.28%(2/61), respectively. The results suggested that the suspected contagious caprine pleuropneumonia in the province were mycoplasma pneumonia of sheep and goats caused mainly by M.ovipneumoniae. The finding would lead to effective prevention and treatment measures for the diseases.
2017, 32(1): 17-21.
doi: 10.19303/j.issn.1008-0384.2017.01.004
Abstract:
An experimentation was conducted to determine the effect of the addition of laminarin in feed on the growth, body composition and immunity of pearl gentian groupers at an aquaculture farm.Four separate 30 m2 concrete pools were used as a closed circulating water aquaculture system for the experiment. Simultaneously, approximately 1 800 groupers were placed in each of two pools for the treatment or control. The initial weight of the individual fish was (275.55±29.79) g. They were fed with either a control diet or one containing 0.6% laminarin in the pools for 66 d. At end of the feeding period, the weight gain of the groupers in the treatment group increased 29.03% (P < 0.05), the specific growth ratio increased 23.88% (P < 0.05), and the feed conversion rate decreased 15.20% (P < 0.05) over those of control, while the nutrient content in flesh of the treatment showed no significant difference as compared with control (P>0.05). For each kg weight gain on the fish, the cost of the treatment diet was 1.96 yuan less than that of control, i.e., a reduction of 12.54%. On the other hand, the activities of alkaline phosphatase, lysozyme and total superoxide dismutase enzymes of the groupers in the treatment group were significantly higher than those of control (P < 0.05). It was, thus, concluded that addition of 0.6% laminarin in the regular feed would improve the growth and enhance the immunity of pearl gentian groupers in aquaculture.
An experimentation was conducted to determine the effect of the addition of laminarin in feed on the growth, body composition and immunity of pearl gentian groupers at an aquaculture farm.Four separate 30 m2 concrete pools were used as a closed circulating water aquaculture system for the experiment. Simultaneously, approximately 1 800 groupers were placed in each of two pools for the treatment or control. The initial weight of the individual fish was (275.55±29.79) g. They were fed with either a control diet or one containing 0.6% laminarin in the pools for 66 d. At end of the feeding period, the weight gain of the groupers in the treatment group increased 29.03% (P < 0.05), the specific growth ratio increased 23.88% (P < 0.05), and the feed conversion rate decreased 15.20% (P < 0.05) over those of control, while the nutrient content in flesh of the treatment showed no significant difference as compared with control (P>0.05). For each kg weight gain on the fish, the cost of the treatment diet was 1.96 yuan less than that of control, i.e., a reduction of 12.54%. On the other hand, the activities of alkaline phosphatase, lysozyme and total superoxide dismutase enzymes of the groupers in the treatment group were significantly higher than those of control (P < 0.05). It was, thus, concluded that addition of 0.6% laminarin in the regular feed would improve the growth and enhance the immunity of pearl gentian groupers in aquaculture.
2017, 32(1): 22-26.
doi: 10.19303/j.issn.1008-0384.2017.01.005
Abstract:
Varied mixing ratios of discarded peanut vines (PV) and corn stalks (CS) and/or addition of lactic acid bacteria (LAB) with 3% sucrose were studied in 2015 to determine their effects on the quality and storage of the resulting silage. The PV:CS ratios of 10:0, 7:3, 5:5 and 3:7 (on fresh weight basis) were applied. Three replicates for each treatment were used. In addition, samples of 3PV:7CS silage were stored in an above-ground cellar for comparison. After 60 d of fermentation, silage quality was analyzed. The results showed that (1) in the 10:0, 7:3 or 5:5 PV/CS silage, the lactic acid content increased significantly (P < 0.05), while the pH, butyric acid and ammonia nitrogen decreased significantly (P < 0.05) when LAB and sucrose were added; (2) in the 10:0 PV/CS silage with the added LAB and sucrose, the dry matters increased significantly (P < 0.05), and the propionic acid content significantly decreased (P < 0.05); (3) in the 5:5 PV/CS silage with added LAB and sucrose, the acetic acid significantly decreased (P < 0.05); (4) the 3:7 PV/CS silage could deliver acceptable quality without the addition of LAB and sucrose; (5) the 10:0 PV silage could be acceptable for applicationsby adding LAB and sucrose; (6) the baled silage appeared to be better than cellar storage for the fermentation.
Varied mixing ratios of discarded peanut vines (PV) and corn stalks (CS) and/or addition of lactic acid bacteria (LAB) with 3% sucrose were studied in 2015 to determine their effects on the quality and storage of the resulting silage. The PV:CS ratios of 10:0, 7:3, 5:5 and 3:7 (on fresh weight basis) were applied. Three replicates for each treatment were used. In addition, samples of 3PV:7CS silage were stored in an above-ground cellar for comparison. After 60 d of fermentation, silage quality was analyzed. The results showed that (1) in the 10:0, 7:3 or 5:5 PV/CS silage, the lactic acid content increased significantly (P < 0.05), while the pH, butyric acid and ammonia nitrogen decreased significantly (P < 0.05) when LAB and sucrose were added; (2) in the 10:0 PV/CS silage with the added LAB and sucrose, the dry matters increased significantly (P < 0.05), and the propionic acid content significantly decreased (P < 0.05); (3) in the 5:5 PV/CS silage with added LAB and sucrose, the acetic acid significantly decreased (P < 0.05); (4) the 3:7 PV/CS silage could deliver acceptable quality without the addition of LAB and sucrose; (5) the 10:0 PV silage could be acceptable for applicationsby adding LAB and sucrose; (6) the baled silage appeared to be better than cellar storage for the fermentation.
2017, 32(1): 27-30.
doi: 10.19303/j.issn.1008-0384.2017.01.006
Abstract:
This experiment was conducted to study the effects of kinggrass on growth performance and blood physiological and biochemical indexes of geese. A total of 240 28-day-old Hainan indigenous geese with similar body weight were randomly divided into 4 groups with 3 pens of 20 geese per group and fed for 60 days. Three sets of diets were used in this trail were control diet and diet supplemented with 7.5%, 10% or 12.5% kinggrass, respectively. The results showed as follows:1) kinggrass diet significantly improved geese's body weight, daily weight gain, daily feed intake (P < 0.05) and Feed intake/gain of groupⅡ was the lowest (P < 0.05).2) kinggrass diet had no significantly effect on blood Physiological indexes.3) kinggrass diet significantly decreased the GPT, TP and TG content and improved other blood biochemical indexes. In conclusion, kinggrass will not harmful to health of geese, and supplementing 10% kinggrass on goose's diet could improve.
This experiment was conducted to study the effects of kinggrass on growth performance and blood physiological and biochemical indexes of geese. A total of 240 28-day-old Hainan indigenous geese with similar body weight were randomly divided into 4 groups with 3 pens of 20 geese per group and fed for 60 days. Three sets of diets were used in this trail were control diet and diet supplemented with 7.5%, 10% or 12.5% kinggrass, respectively. The results showed as follows:1) kinggrass diet significantly improved geese's body weight, daily weight gain, daily feed intake (P < 0.05) and Feed intake/gain of groupⅡ was the lowest (P < 0.05).2) kinggrass diet had no significantly effect on blood Physiological indexes.3) kinggrass diet significantly decreased the GPT, TP and TG content and improved other blood biochemical indexes. In conclusion, kinggrass will not harmful to health of geese, and supplementing 10% kinggrass on goose's diet could improve.
2017, 32(1): 31-35.
doi: 10.19303/j.issn.1008-0384.2017.01.007
Abstract:
Percentage of breakage and degree of chalkiness of themilled grains from 42 new varieties of rice tested by Fujian Rice Research Institute in 2015 were compared. It was found that thebrakeage rateafter millingand the chalkiness of the grains of theearly-season rice from the test cultivation area at Liangchen were significantly lower than those fromthe other locations. Among all, the grain breakage rate of the mid-season varieties from Xinluo, while the chalkinessfrom Nanjing, was the lowest. For the late-season rice, the grain brakeage and chalkiness rates were the lowest from Zhangzhou. Planting area affectedqualities ofthe rice in varying degrees.For instance, the grain brakeage of the early-season rice was found to be significantly moresensitive to the location where it was cultivatedthan the mid-seasonor the late-season varieties, with the coefficients of variation of 56.0%, 21.6% and 11.0%, respectively.And, on the chalkiness, the early-, mid-and late-season varietiesshowed the coefficients of 35.1%, 34.9% and 31.2%, respectively. Consequently, it seemed appropriate that cultivation localityshould be included in evaluating the grain qualityof a new rice variety in the future. And, Liangchen appeared suitable for regional testing on early-season rice.
Percentage of breakage and degree of chalkiness of themilled grains from 42 new varieties of rice tested by Fujian Rice Research Institute in 2015 were compared. It was found that thebrakeage rateafter millingand the chalkiness of the grains of theearly-season rice from the test cultivation area at Liangchen were significantly lower than those fromthe other locations. Among all, the grain breakage rate of the mid-season varieties from Xinluo, while the chalkinessfrom Nanjing, was the lowest. For the late-season rice, the grain brakeage and chalkiness rates were the lowest from Zhangzhou. Planting area affectedqualities ofthe rice in varying degrees.For instance, the grain brakeage of the early-season rice was found to be significantly moresensitive to the location where it was cultivatedthan the mid-seasonor the late-season varieties, with the coefficients of variation of 56.0%, 21.6% and 11.0%, respectively.And, on the chalkiness, the early-, mid-and late-season varietiesshowed the coefficients of 35.1%, 34.9% and 31.2%, respectively. Consequently, it seemed appropriate that cultivation localityshould be included in evaluating the grain qualityof a new rice variety in the future. And, Liangchen appeared suitable for regional testing on early-season rice.
2017, 32(1): 36-41.
doi: 10.19303/j.issn.1008-0384.2017.01.008
Abstract:
To enrich the resource on potato germplasms for the province, this project introduced 107 germplasms from the Institute of Vegetables and Flowers at the Chinese Academy of Agricultural Sciences in Beijing for evaluation. The morphological characteristics, tuber yield, nutritional quality, dry matter content, low-temperature tolerance, pollen fertility and natural parthenocarpy of 24 of them were scrutinized at test sites in Longhai and Zhouning counties. It was concluded that these germplasms could be used as parents for breeding new winter-potatoes with specific properties.
To enrich the resource on potato germplasms for the province, this project introduced 107 germplasms from the Institute of Vegetables and Flowers at the Chinese Academy of Agricultural Sciences in Beijing for evaluation. The morphological characteristics, tuber yield, nutritional quality, dry matter content, low-temperature tolerance, pollen fertility and natural parthenocarpy of 24 of them were scrutinized at test sites in Longhai and Zhouning counties. It was concluded that these germplasms could be used as parents for breeding new winter-potatoes with specific properties.
2017, 32(1): 42-46.
doi: 10.19303/j.issn.1008-0384.2017.01.009
Abstract:
Field experiments were conducted on cultivation with varied shading materials over the plants to examine their effects on the photosynthesis and flower bud differentiation of vanilla. The shading materials provided 50%, 75%, and 90% shades. Three months after the treatments, the relative chlorophyll content, photosynthetic physiology and chlorophyll fluorescence of the plants were determined. In the following April, ratios of the flower bud formation were recorded. The results showed that the low shading was unfavorable for the chlorophyll formation on the plants. Within a certain range of the shading, the apparent quantum yield (AQY), effective quantum yield of photosystemⅡ(ФPSⅡ) and efficiency of excitation captured by open PSII center (Fv'/Fm') increased with increasing shading. On the other hand, the net photosynthetic rate (Pn), stomatal conductance (Gs), light saturation point (LSP), dark respiration rate (Rd), potential photochemical efficiency (Fv/Fo), maximum photochemical efficiency (Fv/Fm), electron transport rat (ETR) and photochemical quenching coefficient (qP) increased initially and then decreased with increasing shading. The rate of flower bud formation was up to 54.98% with the 75% shading. Thus, it appeared that 75% shading could be conducive to the vanilla growth, and applicable for its cultivation.
Field experiments were conducted on cultivation with varied shading materials over the plants to examine their effects on the photosynthesis and flower bud differentiation of vanilla. The shading materials provided 50%, 75%, and 90% shades. Three months after the treatments, the relative chlorophyll content, photosynthetic physiology and chlorophyll fluorescence of the plants were determined. In the following April, ratios of the flower bud formation were recorded. The results showed that the low shading was unfavorable for the chlorophyll formation on the plants. Within a certain range of the shading, the apparent quantum yield (AQY), effective quantum yield of photosystemⅡ(ФPSⅡ) and efficiency of excitation captured by open PSII center (Fv'/Fm') increased with increasing shading. On the other hand, the net photosynthetic rate (Pn), stomatal conductance (Gs), light saturation point (LSP), dark respiration rate (Rd), potential photochemical efficiency (Fv/Fo), maximum photochemical efficiency (Fv/Fm), electron transport rat (ETR) and photochemical quenching coefficient (qP) increased initially and then decreased with increasing shading. The rate of flower bud formation was up to 54.98% with the 75% shading. Thus, it appeared that 75% shading could be conducive to the vanilla growth, and applicable for its cultivation.
2017, 32(1): 47-50.
doi: 10.19303/j.issn.1008-0384.2017.01.010
Abstract:
Genetic diversity of 50 Prunus persica germplasms was analyzed using 16 pairs of SSR primers. The results showed that the polymorphism information contents of the individual sites ranged from 0.04 to 0.37 with an average of 0.24. The 50 peach germplasms could be classified into 3 groups according to thecluster analysis of the unweighted pair group method witharithmetic mean. They were medium late-maturing, medium early-maturing and low-temp early-maturing peaches. In addition, the low-temp germplasms with excellent over-all properties in the hot and humid southern regions could be grouped by themselves. The ornamental varieties were genetically far remote from the common peaches. A genetic analysis indicated that some of the local germplasms found in Fujian were typical southern peaches. Thus, from the molecular level, it confirmed the previous understanding of the origin of local varieties to be south of the Yangtze River.
Genetic diversity of 50 Prunus persica germplasms was analyzed using 16 pairs of SSR primers. The results showed that the polymorphism information contents of the individual sites ranged from 0.04 to 0.37 with an average of 0.24. The 50 peach germplasms could be classified into 3 groups according to thecluster analysis of the unweighted pair group method witharithmetic mean. They were medium late-maturing, medium early-maturing and low-temp early-maturing peaches. In addition, the low-temp germplasms with excellent over-all properties in the hot and humid southern regions could be grouped by themselves. The ornamental varieties were genetically far remote from the common peaches. A genetic analysis indicated that some of the local germplasms found in Fujian were typical southern peaches. Thus, from the molecular level, it confirmed the previous understanding of the origin of local varieties to be south of the Yangtze River.
2017, 32(1): 51-55.
doi: 10.19303/j.issn.1008-0384.2017.01.011
Abstract:
By varying the harvest time, processing method and cropping practice, the productivity and content of active ingredients in the Pseudostellaria heterophylla roots harvested were studied. It was found that (a) delayed harvestingreduced the yield and polysaccharide content in the roots; (b) crop harvested at a time between early and late peroid had a lower moisture and higher ash content than either period; (c) processing method affected significantly on the contents of ash, polysaccharides, and saponins of the finished product; (d) the greatest polysaccharide content in thefinished product was achieved bydrying in the shade (F1) followed by blanching (F3);(e) the highestsaponin content was foundin the product dried in the shade, and thelowest by blanching; (f) content ofactive ingredients could be maximized by drying in the shade, but, the processing cost wasminimal if sun-drying was used; (g) continuously cropped P.heterophylla produced roots with 1.20 times higherpolysaccharide content than control.
By varying the harvest time, processing method and cropping practice, the productivity and content of active ingredients in the Pseudostellaria heterophylla roots harvested were studied. It was found that (a) delayed harvestingreduced the yield and polysaccharide content in the roots; (b) crop harvested at a time between early and late peroid had a lower moisture and higher ash content than either period; (c) processing method affected significantly on the contents of ash, polysaccharides, and saponins of the finished product; (d) the greatest polysaccharide content in thefinished product was achieved bydrying in the shade (F1) followed by blanching (F3);(e) the highestsaponin content was foundin the product dried in the shade, and thelowest by blanching; (f) content ofactive ingredients could be maximized by drying in the shade, but, the processing cost wasminimal if sun-drying was used; (g) continuously cropped P.heterophylla produced roots with 1.20 times higherpolysaccharide content than control.
2017, 32(1): 56-59.
doi: 10.19303/j.issn.1008-0384.2017.01.012
Abstract:
The ectoenzyme activity and the virulence against Planococcus citri of Metarhizium anisopliae F061 were determined in the laboratory. Their correlation was established using a linear regression analysis. The activities of two ectoenzymes from the bacteria were high.At concentrations of 1.00×108 and 1.00×107 conidia·mL-1, the protease activities of the spores were 7.63 U·mL-1 and 7.61 U·mL-1, respectively; while the chitinase activities, 5.45 U·mL-1 and 5.67 U·mL-1, respectively; and, the LT50 of the strain against P.citri, 4.98 d and 5.39 d, respectively. The LT50 inversely correlated significantly with the protease activity, but moderately with the chitinase activity. It appeared that the protease were stronger than the chitinase in M.anisopliae F061, and thus, played a more critical role in infecting P. citri.
The ectoenzyme activity and the virulence against Planococcus citri of Metarhizium anisopliae F061 were determined in the laboratory. Their correlation was established using a linear regression analysis. The activities of two ectoenzymes from the bacteria were high.At concentrations of 1.00×108 and 1.00×107 conidia·mL-1, the protease activities of the spores were 7.63 U·mL-1 and 7.61 U·mL-1, respectively; while the chitinase activities, 5.45 U·mL-1 and 5.67 U·mL-1, respectively; and, the LT50 of the strain against P.citri, 4.98 d and 5.39 d, respectively. The LT50 inversely correlated significantly with the protease activity, but moderately with the chitinase activity. It appeared that the protease were stronger than the chitinase in M.anisopliae F061, and thus, played a more critical role in infecting P. citri.
2017, 32(1): 60-62.
doi: 10.19303/j.issn.1008-0384.2017.01.013
Abstract:
Eriophyes hybridicola Keifer (Acari:Eriophyidae) is recorded from plum bud for the first time in Liancheng County, Fujian, China. The population of this mite mainly inhabits the buds and petiole bases on new growth inducing abnormal bud proliferation and the formation of solitary or fascicled gall. The injured bud can't germinate, blossom and bear fruit. It differs from two previously described Eriophyes mites on Prunus, namely insidiosus and prunidenzissne, by the lateral shield pattern. The investigation results showed that this Eriophyid mite mainly overwinters as adults beneath live bud scales.The adult mite transfers and spreads from inside to outside of overwintering bud gall and attack new bud during early stage of new bud formation. Besides, According to the occurrence regularity of E. hybridicola Keifer, concerning control measures were suggested in the paper.
Eriophyes hybridicola Keifer (Acari:Eriophyidae) is recorded from plum bud for the first time in Liancheng County, Fujian, China. The population of this mite mainly inhabits the buds and petiole bases on new growth inducing abnormal bud proliferation and the formation of solitary or fascicled gall. The injured bud can't germinate, blossom and bear fruit. It differs from two previously described Eriophyes mites on Prunus, namely insidiosus and prunidenzissne, by the lateral shield pattern. The investigation results showed that this Eriophyid mite mainly overwinters as adults beneath live bud scales.The adult mite transfers and spreads from inside to outside of overwintering bud gall and attack new bud during early stage of new bud formation. Besides, According to the occurrence regularity of E. hybridicola Keifer, concerning control measures were suggested in the paper.
2017, 32(1): 63-67.
doi: 10.19303/j.issn.1008-0384.2017.01.014
Abstract:
A vasicinol-producing strain of Bacillus methylotrophicus FJAT-16022 was screened from 14 Bacillus-like bacteria with an aid of liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF MS) combined with retrieval comparison against the mass spectrometry database, Metlin. The obtained vasicinol had a matching score of 95.1 with the database, and its relative content was up to 1.73% of the total metabolites in the cultural supernatants. It appeared that B. methylotrophicus FJAT-16022 was a high-yield strain in producing vasicinol. The result obtained paved the way for the development and utilization of vasicinol from the identified bacterium.
A vasicinol-producing strain of Bacillus methylotrophicus FJAT-16022 was screened from 14 Bacillus-like bacteria with an aid of liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF MS) combined with retrieval comparison against the mass spectrometry database, Metlin. The obtained vasicinol had a matching score of 95.1 with the database, and its relative content was up to 1.73% of the total metabolites in the cultural supernatants. It appeared that B. methylotrophicus FJAT-16022 was a high-yield strain in producing vasicinol. The result obtained paved the way for the development and utilization of vasicinol from the identified bacterium.
2017, 32(1): 68-74.
doi: 10.19303/j.issn.1008-0384.2017.01.015
Abstract:
Accumulation and health risks of heavy metals in the soils around a mine in Fujian were studied. Contents of Cd, Pb and Cr in the agricultural fields nearby were determined. Heavy metal pollution on the soil and damages to the ecology were evaluated based on various indices, and the health risks to humans were assessed using a probability assessment model. The results showed that the soils in the surveyed areas were contaminated by Cd, Pb and Cr to varying extents. The average individual pollutant index on the metals ranked in the order of Cd > Pb > Cr, and the over-all pollution index was 1.21 implying that the soils were under a lightly polluted condition. The average potential ecological risk was Cd > Pb > Cr with a comprehensive ecological risk index of 226 indicating a medium level of ecological hazard. The Cd in the soils was assessed to belower than 10-4, a level less likely to risk cancers in humans as suggested by experts. The non-carcinogen risks index on Pb did not exceed the accepted limit of 1, which ought not to cause any health concerns. On the other hand, the Cr contamination in the soils made the carcinogenic risk index 12.9% greater than the threshold value of 10-4 that could post a thread to human health.
Accumulation and health risks of heavy metals in the soils around a mine in Fujian were studied. Contents of Cd, Pb and Cr in the agricultural fields nearby were determined. Heavy metal pollution on the soil and damages to the ecology were evaluated based on various indices, and the health risks to humans were assessed using a probability assessment model. The results showed that the soils in the surveyed areas were contaminated by Cd, Pb and Cr to varying extents. The average individual pollutant index on the metals ranked in the order of Cd > Pb > Cr, and the over-all pollution index was 1.21 implying that the soils were under a lightly polluted condition. The average potential ecological risk was Cd > Pb > Cr with a comprehensive ecological risk index of 226 indicating a medium level of ecological hazard. The Cd in the soils was assessed to belower than 10-4, a level less likely to risk cancers in humans as suggested by experts. The non-carcinogen risks index on Pb did not exceed the accepted limit of 1, which ought not to cause any health concerns. On the other hand, the Cr contamination in the soils made the carcinogenic risk index 12.9% greater than the threshold value of 10-4 that could post a thread to human health.
2017, 32(1): 75-81.
doi: 10.19303/j.issn.1008-0384.2017.01.016
Abstract:
Spatial distribution of water repellency of the soils from plots planted with different crops was studied under the dry, moderately or wet soil conditions. Soybeans, sugarcane or pear trees were grown on the plots in the karst region near Guilin Institute of Agricultural Sciences in Guangxi. The spatial distribution of water repellency in the soils from the plots was determined by using a geostatistical analysis on the plots of 135 m×105 m in size. There were 100 sampling points on each plot for measurement of water drop penetration time (WDPT). The soils were also classified according to their moisture content as dry (0.062±0.025) cm3·cm-3, moderately (0.151±0.045) cm3·cm-3 or wet (0.237±0.086) cm3·cm-3. The results showed that, under dry and wet conditions, the greatest WDPT and contents of moisture and organic matters were found in the soil where pear trees were grown, while the lowest on the soybean plot. However, under the moderately wet soil condition, the lowest values on these parameters were on the sugarcane plot. Meanwhile, the water retention time reached a maximum for all plots. It appeared that geostatiatical analysis significant correlation existed among the spatial distribution of water repellencies in 3 planting plots under 3 soil conditions as the ratio was substantially greater than 75%.Due to the high threshold water repellency distribution, the soil at the sugarcane plot seemed to be more stable than that at the soybean field, while that at the pear tree plot being the weakest of all. It suggested that the soils might be able to recover spatial distribution of water repellency after being disturbed by human activity.
Spatial distribution of water repellency of the soils from plots planted with different crops was studied under the dry, moderately or wet soil conditions. Soybeans, sugarcane or pear trees were grown on the plots in the karst region near Guilin Institute of Agricultural Sciences in Guangxi. The spatial distribution of water repellency in the soils from the plots was determined by using a geostatistical analysis on the plots of 135 m×105 m in size. There were 100 sampling points on each plot for measurement of water drop penetration time (WDPT). The soils were also classified according to their moisture content as dry (0.062±0.025) cm3·cm-3, moderately (0.151±0.045) cm3·cm-3 or wet (0.237±0.086) cm3·cm-3. The results showed that, under dry and wet conditions, the greatest WDPT and contents of moisture and organic matters were found in the soil where pear trees were grown, while the lowest on the soybean plot. However, under the moderately wet soil condition, the lowest values on these parameters were on the sugarcane plot. Meanwhile, the water retention time reached a maximum for all plots. It appeared that geostatiatical analysis significant correlation existed among the spatial distribution of water repellencies in 3 planting plots under 3 soil conditions as the ratio was substantially greater than 75%.Due to the high threshold water repellency distribution, the soil at the sugarcane plot seemed to be more stable than that at the soybean field, while that at the pear tree plot being the weakest of all. It suggested that the soils might be able to recover spatial distribution of water repellency after being disturbed by human activity.
2017, 32(1): 82-86.
doi: 10.19303/j.issn.1008-0384.2017.01.017
Abstract:
This study aimed to obtain a highly efficient expression of cyclodextrin glycosyltransferase (CGTase) in Pichia pastoris. The optimized CGT2 was cloned into a yeast constitutive expression vector, pGATZαA.The recombinant plasmid pGAPZαA-CGT2 was then transformed into P. pastoris by electroporation to construct an engineered strain, X33/pGAPZαA-CGT2.After cultivating for 120 h in a shaking flask, CGT2 with an activity of 0.21 U·mL-1 was obtained. Experiments were conducted to further optimize the fermentation conditions. As a result, the greatest activity of 1.26 U·mL-1, achieving a 1.7-fold improvement, for the enzyme was reached by induction for 120 h at pH 6.5 and 28℃ with a constant shaking at 200 r·min-1 and replenishing with 2.5% glycerol every 24 h in the flask.
This study aimed to obtain a highly efficient expression of cyclodextrin glycosyltransferase (CGTase) in Pichia pastoris. The optimized CGT2 was cloned into a yeast constitutive expression vector, pGATZαA.The recombinant plasmid pGAPZαA-CGT2 was then transformed into P. pastoris by electroporation to construct an engineered strain, X33/pGAPZαA-CGT2.After cultivating for 120 h in a shaking flask, CGT2 with an activity of 0.21 U·mL-1 was obtained. Experiments were conducted to further optimize the fermentation conditions. As a result, the greatest activity of 1.26 U·mL-1, achieving a 1.7-fold improvement, for the enzyme was reached by induction for 120 h at pH 6.5 and 28℃ with a constant shaking at 200 r·min-1 and replenishing with 2.5% glycerol every 24 h in the flask.
2017, 32(1): 87-92.
doi: 10.19303/j.issn.1008-0384.2017.01.018
Abstract:
Enzyme addition in the hot water extraction of flavonoids from Ganoderma lucidum was investigated for improvements on the extraction efficiency and/or enhancement on the antioxidant activity of the extract. The single factor test and the response surface methodology were used to optimize the processing conditions. It was found that a maximized yield of flavonoids of 0.75 mg/g could be obtained with the use of a combination of cellulase, pectinase and neutral proteinase in the ratio of 2.07:0.86:2.11 for the extraction at pH 5.0 and 50oC for 80 min. The resulting extract exhibited a high reducing power as well as free radical scavenging activities on DPPH and hydroxyl free radicals.
Enzyme addition in the hot water extraction of flavonoids from Ganoderma lucidum was investigated for improvements on the extraction efficiency and/or enhancement on the antioxidant activity of the extract. The single factor test and the response surface methodology were used to optimize the processing conditions. It was found that a maximized yield of flavonoids of 0.75 mg/g could be obtained with the use of a combination of cellulase, pectinase and neutral proteinase in the ratio of 2.07:0.86:2.11 for the extraction at pH 5.0 and 50oC for 80 min. The resulting extract exhibited a high reducing power as well as free radical scavenging activities on DPPH and hydroxyl free radicals.
2017, 32(1): 93-98.
doi: 10.19303/j.issn.1008-0384.2017.01.019
Abstract:
Nutrient film technique (NFT) provides the advantages of rendering consistent high output and easy production scale-upin conducting experiments on plant cultivation. In order to maximizeprocess efficiency and develop potentials. NFT Cultivation Tester was developed. The tester consisted of a fertilizer mixing barrel for blending and storing nutrient solution, a group of cultivation tanks with exchangable covers, an irrigation pump, a mixing pump, a solenoid valve, an electric drain valve, a UV sterilizer, and a temperature sensor, as well as EC, pH and electrical control systems.All components were mounted on a sturdy stainless steel frame. Like the mainstream NFT vegetable cultivation systems, the tester also allowed the nutrient solution held in the mixing barrel run through a series of parallel cultivation tanks, a filter, andan online UV sterilizer before returning to the barrel by a controlled irrigation pump. As the core of electrical control system, HMI read ambient temperature, humidity, illumination, as well as the temperature, EC, and pH of the nutrient solution by various sensors. With the communication protocol, RS485/MODBUS, the operations of the peripheral equipment were controlled with input output boards. The software package contained the automatic functions including fertilizer mixing, barrel cleaning, tank washing, water replenishment, irrigationplanning, monitoring/alarm, and data logging. The system was also equipped with manual irrigation and emergency stop functions. Spacing and number of plants for testing could be easily adjusted by using cultivation tank covers of varied spacings and holes. A typical test might use 8 tanks with covers having holes sapced 20 cm center-to-center apart to handle 200 plants simultaneously for 8 treatments. Any experiment for crop variety selection and/or disease resistance could be efficiently conducted in a NFT Cultivation Tester. By using multiple Testers, optimizations on nutrient solution formulation, irrigation parameters, etc. might be conducted without difficulty.
Nutrient film technique (NFT) provides the advantages of rendering consistent high output and easy production scale-upin conducting experiments on plant cultivation. In order to maximizeprocess efficiency and develop potentials. NFT Cultivation Tester was developed. The tester consisted of a fertilizer mixing barrel for blending and storing nutrient solution, a group of cultivation tanks with exchangable covers, an irrigation pump, a mixing pump, a solenoid valve, an electric drain valve, a UV sterilizer, and a temperature sensor, as well as EC, pH and electrical control systems.All components were mounted on a sturdy stainless steel frame. Like the mainstream NFT vegetable cultivation systems, the tester also allowed the nutrient solution held in the mixing barrel run through a series of parallel cultivation tanks, a filter, andan online UV sterilizer before returning to the barrel by a controlled irrigation pump. As the core of electrical control system, HMI read ambient temperature, humidity, illumination, as well as the temperature, EC, and pH of the nutrient solution by various sensors. With the communication protocol, RS485/MODBUS, the operations of the peripheral equipment were controlled with input output boards. The software package contained the automatic functions including fertilizer mixing, barrel cleaning, tank washing, water replenishment, irrigationplanning, monitoring/alarm, and data logging. The system was also equipped with manual irrigation and emergency stop functions. Spacing and number of plants for testing could be easily adjusted by using cultivation tank covers of varied spacings and holes. A typical test might use 8 tanks with covers having holes sapced 20 cm center-to-center apart to handle 200 plants simultaneously for 8 treatments. Any experiment for crop variety selection and/or disease resistance could be efficiently conducted in a NFT Cultivation Tester. By using multiple Testers, optimizations on nutrient solution formulation, irrigation parameters, etc. might be conducted without difficulty.
2017, 32(1): 99-106.
doi: 10.19303/j.issn.1008-0384.2017.01.020
Abstract:
Considering to both agriculture growth and carbon dioxide emission, growth of agricultural total factor productivity (TFP) of 30 provinces of China from 1995 to 2014 under carbon emissions constraints, were analyzed using the Global Malmquist-Luenberger, and were compared to the traditional Malmquist productivity index; and then the convergence of which were further examined. The results showed that:Agricultural total factor productivity growth under carbon emissions constrains was mainly owing to technical progress or both technical progress and technical efficiency.There were distinct differences among provincial and regional agricultural total factor productivity. The agriculture in Hebei, Liaoning, Heilongjiang and Hunan Province were low carbon. And the growth of agricultural total factor productivity was fast in central, north and east China, medium in northwest and northeast, but slow in south and southwest. A trend of σ convergence was shown among provinces, but not stable. There was absolute β convergence in whole, north, northeast, east, central and south China, but not in southwest and northwest areas. China and other seven areas showed conditional β convergence which developed toward stable states.
Considering to both agriculture growth and carbon dioxide emission, growth of agricultural total factor productivity (TFP) of 30 provinces of China from 1995 to 2014 under carbon emissions constraints, were analyzed using the Global Malmquist-Luenberger, and were compared to the traditional Malmquist productivity index; and then the convergence of which were further examined. The results showed that:Agricultural total factor productivity growth under carbon emissions constrains was mainly owing to technical progress or both technical progress and technical efficiency.There were distinct differences among provincial and regional agricultural total factor productivity. The agriculture in Hebei, Liaoning, Heilongjiang and Hunan Province were low carbon. And the growth of agricultural total factor productivity was fast in central, north and east China, medium in northwest and northeast, but slow in south and southwest. A trend of σ convergence was shown among provinces, but not stable. There was absolute β convergence in whole, north, northeast, east, central and south China, but not in southwest and northwest areas. China and other seven areas showed conditional β convergence which developed toward stable states.
