2015 Vol. 6, No. 3
Abstract
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2015, 6(3): 229-234.
doi: 10.15886/j.cnki.rdswxb.2015.03.001
Abstract:
White-leg shrimps（ Litopenaeus vannamei） bred by selection for eight years were cultured without discharge of sewage,change of water,air ventilation and cleaning of dead shrimps in outdoor cement pools A and B. The remaining shrimps cultured in the pools A and B for a year were used as parents,and forty- four lines of F1 generation were bred from the pools A and B. Thirteen lines of the shrimps were selected to compare their growth,stress tolerance and resistance to WSSV to study the genetic characters of the stress-tolerant lines of L.vannamei. Each F1 generation of the shrimps was found to have a significant difference in the growth（ P ＜ 0. 05）.The line F1-08 in the pool A（ A F1-08） had an average body weight of 28. 63 g,the highest in the pool A. At the salinity from 28‰ to 5‰ the line F1-12 in the pool B（ B F1-12） had a mortality or death rate of 23. 33%,the lowest in the pool B. The F1 generation was significantly higher in mortality in the pool A than that in the pool B and the F1 generation of crosses between the shrimps in the pools A and B（ P ＜0. 05）. The F1 generation in the pool B and that of crosses between the A and B pools（ AB F1） had a lower mortality than the control groups Gjk and Klw and a significant higher mortality than the control Sis（ P ＜0. 05）. At the concentration of ammonia nitrogen of 31. 67 mg·L-1 each F1 generation of the shrimps was significantly different in the mortality（ P ＜0. 05） and was significantly lower than the control group Sis（ P ＜0. 05）. The A F1-09,A F1-13,A F1-19,A F1-20,A F1-13 and A F1-08 had a mortality of 0%,the lowest. At the concentration of nitrite of 50. 51mg·L-1 each F1 generation of the shrimps was significantly different in mortality（ P ＜0. 05）,and lower than the control groups Gjk,Klw and Sis（ P ＜0. 05）. The A F1-08,A F1-10,A F1-18,A F1-19 and A F1-20 were the lowest in mortality（ 0）. After infected with WSSV,the B F1-13 had a mortality of 53. 30%,which was the lowest and significantly lower than the control group F2（ P ＜0. 05）. The A F1-08 had remarkably higher growth,the B F1 and AB F1 had a stronger ability for adaptation to the sudden change of salinity. All the F1 generations had a higher adaptation to the sudden change of ammonia nitrogen concentration than the control Sis and to the sudden change of nitrite concentration than the controls Gjk,Klw and Sis. The BF1-13 had a higher resistance to WSSV. The findings provide evidence for selective breeding of new tolerant lines of L. vannamei.
White-leg shrimps（ Litopenaeus vannamei） bred by selection for eight years were cultured without discharge of sewage,change of water,air ventilation and cleaning of dead shrimps in outdoor cement pools A and B. The remaining shrimps cultured in the pools A and B for a year were used as parents,and forty- four lines of F1 generation were bred from the pools A and B. Thirteen lines of the shrimps were selected to compare their growth,stress tolerance and resistance to WSSV to study the genetic characters of the stress-tolerant lines of L.vannamei. Each F1 generation of the shrimps was found to have a significant difference in the growth（ P ＜ 0. 05）.The line F1-08 in the pool A（ A F1-08） had an average body weight of 28. 63 g,the highest in the pool A. At the salinity from 28‰ to 5‰ the line F1-12 in the pool B（ B F1-12） had a mortality or death rate of 23. 33%,the lowest in the pool B. The F1 generation was significantly higher in mortality in the pool A than that in the pool B and the F1 generation of crosses between the shrimps in the pools A and B（ P ＜0. 05）. The F1 generation in the pool B and that of crosses between the A and B pools（ AB F1） had a lower mortality than the control groups Gjk and Klw and a significant higher mortality than the control Sis（ P ＜0. 05）. At the concentration of ammonia nitrogen of 31. 67 mg·L-1 each F1 generation of the shrimps was significantly different in the mortality（ P ＜0. 05） and was significantly lower than the control group Sis（ P ＜0. 05）. The A F1-09,A F1-13,A F1-19,A F1-20,A F1-13 and A F1-08 had a mortality of 0%,the lowest. At the concentration of nitrite of 50. 51mg·L-1 each F1 generation of the shrimps was significantly different in mortality（ P ＜0. 05）,and lower than the control groups Gjk,Klw and Sis（ P ＜0. 05）. The A F1-08,A F1-10,A F1-18,A F1-19 and A F1-20 were the lowest in mortality（ 0）. After infected with WSSV,the B F1-13 had a mortality of 53. 30%,which was the lowest and significantly lower than the control group F2（ P ＜0. 05）. The A F1-08 had remarkably higher growth,the B F1 and AB F1 had a stronger ability for adaptation to the sudden change of salinity. All the F1 generations had a higher adaptation to the sudden change of ammonia nitrogen concentration than the control Sis and to the sudden change of nitrite concentration than the controls Gjk,Klw and Sis. The BF1-13 had a higher resistance to WSSV. The findings provide evidence for selective breeding of new tolerant lines of L. vannamei.
2015, 6(3): 235-241.
doi: 10.15886/j.cnki.rdswxb.2015.03.002
Abstract:
Five biofilter media,bacterial ball,white glass ring,volcanic rock,red breathing loop and coral sandstone,were used to remove dissolved NH4+-N,NO2-N and NO3--N in the seawater in a closed recirculation aquaculture system by using the natural biofilm cultivation method,and to examine the change of and the relation among NH4+-N,NO2-N and NO3--N in the seawater after the biofilm maturation. During biofilm cultivation,these biofilter media were found to reduce the NH4+-N concentrations over time,increase initially and then decrease the NO2-N concentrations,and increase gradually the NO3--N concentrations. The coral sandstone and the red breathing loop were better than other media in removing inorganic nitrogen. They formed biofilms in about 23 days and reduced the ammonia concentrations to 0. 215 mg·L-1 at day 15 after biofilm formation,with a NH4+-N removal rate of upto 98. 5%. After biofilm maturation,the exponential equation y = ae-bx was fitted to the data of the NH4+-N removal efficiencies of each biofilter medium,and the equation y = 1/（a+b/xlnx +c/x） fitted to the data of the NO2-N and NO3--N removal efficiencies. Moreover,the relationship between the NH4+-N concentration and the NO2-N concentration or the NO3--N concentration in the sea water was also fitted by using the exponential equation y = ae-bx.
Five biofilter media,bacterial ball,white glass ring,volcanic rock,red breathing loop and coral sandstone,were used to remove dissolved NH4+-N,NO2-N and NO3--N in the seawater in a closed recirculation aquaculture system by using the natural biofilm cultivation method,and to examine the change of and the relation among NH4+-N,NO2-N and NO3--N in the seawater after the biofilm maturation. During biofilm cultivation,these biofilter media were found to reduce the NH4+-N concentrations over time,increase initially and then decrease the NO2-N concentrations,and increase gradually the NO3--N concentrations. The coral sandstone and the red breathing loop were better than other media in removing inorganic nitrogen. They formed biofilms in about 23 days and reduced the ammonia concentrations to 0. 215 mg·L-1 at day 15 after biofilm formation,with a NH4+-N removal rate of upto 98. 5%. After biofilm maturation,the exponential equation y = ae-bx was fitted to the data of the NH4+-N removal efficiencies of each biofilter medium,and the equation y = 1/（a+b/xlnx +c/x） fitted to the data of the NO2-N and NO3--N removal efficiencies. Moreover,the relationship between the NH4+-N concentration and the NO2-N concentration or the NO3--N concentration in the sea water was also fitted by using the exponential equation y = ae-bx.
2015, 6(3): 242-245.
doi: 10.15886/j.cnki.rdswxb.2015.03.003
Abstract:
The oyster shell powders were modified by rare earth coupling agent and mixed with natural rubber to prepare the natural rubber/oyster shell powder composites. The particle size and distribution of the oyster shell powders were determined with particle size analyzer,and the microstructures of the composites were characterized by using the FTIR to analyze the cure characteristics of the composites. The particle size of the oyster shell powder was found 150- 275 nm,averaging 209 nm. The composites kept the FTIR absorption features of both the oyster shell powder and the natural rubber. In vulcanization,the torque values of the composites decreased,but the scorch and optimum cure time of the composites increased with the increase of the rare earth coupling agent.The torque values and the scorch and optimum cure time of the composites increased when mixed with the oyster shell powder,and the reversion process of cured natural rubber disappeared. Overall,the curing performance of the composites was improved by adding the oyster shell powder.
The oyster shell powders were modified by rare earth coupling agent and mixed with natural rubber to prepare the natural rubber/oyster shell powder composites. The particle size and distribution of the oyster shell powders were determined with particle size analyzer,and the microstructures of the composites were characterized by using the FTIR to analyze the cure characteristics of the composites. The particle size of the oyster shell powder was found 150- 275 nm,averaging 209 nm. The composites kept the FTIR absorption features of both the oyster shell powder and the natural rubber. In vulcanization,the torque values of the composites decreased,but the scorch and optimum cure time of the composites increased with the increase of the rare earth coupling agent.The torque values and the scorch and optimum cure time of the composites increased when mixed with the oyster shell powder,and the reversion process of cured natural rubber disappeared. Overall,the curing performance of the composites was improved by adding the oyster shell powder.
2015, 6(3): 246-249,268.
doi: 10.15886/j.cnki.rdswxb.2015.03.004
Abstract:
The position and number of 45 S rDNA on mitotic chromosomes of the young leaf collected from the rubber tree of Clone Reyan7-33-97（ Hevea brasiliensis Müll. Arg.） at the bronze leaf stage were detected by using fluorescence in situ hybridization（ FISH） analysis with 45 S rDNA from wheat as a probe. Four hybridization signals with different sizes and strength were found in different mitotic phases. According to the karyotype analysis,the loci of 4 signals were found on chromosomes pairs 6 and 7. A small faint signal was detected at the secondary constriction of one member of chromosome pair 6,and a large strong signal was detected at the secondary constriction and satellite of another member of chromosome pair 6. The other two signals with their sizes and strength between those of the members of chromosome pair 6 were all detected at the secondary constriction and satellite of chromosome pair 7.
The position and number of 45 S rDNA on mitotic chromosomes of the young leaf collected from the rubber tree of Clone Reyan7-33-97（ Hevea brasiliensis Müll. Arg.） at the bronze leaf stage were detected by using fluorescence in situ hybridization（ FISH） analysis with 45 S rDNA from wheat as a probe. Four hybridization signals with different sizes and strength were found in different mitotic phases. According to the karyotype analysis,the loci of 4 signals were found on chromosomes pairs 6 and 7. A small faint signal was detected at the secondary constriction of one member of chromosome pair 6,and a large strong signal was detected at the secondary constriction and satellite of another member of chromosome pair 6. The other two signals with their sizes and strength between those of the members of chromosome pair 6 were all detected at the secondary constriction and satellite of chromosome pair 7.
2015, 6(3): 250-255.
doi: 10.15886/j.cnki.rdswxb.2015.03.005
Abstract:
Study on flowering mechanism is important for shortening the breeding cycle of rubber tree. Here,two LFY homologous genes,HbLFY1 and HbLFY2,were cloned from Hevea brasiliensis,and then over-expressed in the Wild-type and LFY mutant Arabidopsis thaliana. Statistical results showed that the HbLFY genes did not significantly promote early flowering in Arabidopsis,indicating that HbLFYs are not the key genes regulating flowering time of rubber tree.
Study on flowering mechanism is important for shortening the breeding cycle of rubber tree. Here,two LFY homologous genes,HbLFY1 and HbLFY2,were cloned from Hevea brasiliensis,and then over-expressed in the Wild-type and LFY mutant Arabidopsis thaliana. Statistical results showed that the HbLFY genes did not significantly promote early flowering in Arabidopsis,indicating that HbLFYs are not the key genes regulating flowering time of rubber tree.
2015, 6(3): 256-260.
doi: 10.15886/j.cnki.rdswxb.2015.03.006
Abstract:
Jasmonic acid（JA） is one of the most important phytohormones for regulation of latex biosynthesis in Hevea brasiliensis. HbCoi1 is the receptor of JA signaling pathway. Analysis of the gene expression of HbCoi1 is of great significance to reveal molecular mechanism of latex biosynthesis in H. brasiliensis. In this context,the promoter of HbCoi1 was PCR amplified and inserted into pHis2. 1 vector to construct bait vector p HIS-HbCoi1 for yeast-one-hybrid. The vector was then transformed into Y187 yeast strain and cultured on the SD medium to test the auto-activity of the transcription. The growth of the strain containing bait vector was inhibited on the SD medium added with 10 mmol·L-1 3-AT. Furthermore,p HIS-HbCoi1 vector and p GADT7-rec2 cDNA library of H.brasiliensis were co-transformed into Y187 strain,and several proteins interacted with HbCoi1 promoter were identified,including DNA binding protein,ribosomal proteins and uncharacterized proteins,which lays a foundation for further study of gene expression of HbCoi1.
Jasmonic acid（JA） is one of the most important phytohormones for regulation of latex biosynthesis in Hevea brasiliensis. HbCoi1 is the receptor of JA signaling pathway. Analysis of the gene expression of HbCoi1 is of great significance to reveal molecular mechanism of latex biosynthesis in H. brasiliensis. In this context,the promoter of HbCoi1 was PCR amplified and inserted into pHis2. 1 vector to construct bait vector p HIS-HbCoi1 for yeast-one-hybrid. The vector was then transformed into Y187 yeast strain and cultured on the SD medium to test the auto-activity of the transcription. The growth of the strain containing bait vector was inhibited on the SD medium added with 10 mmol·L-1 3-AT. Furthermore,p HIS-HbCoi1 vector and p GADT7-rec2 cDNA library of H.brasiliensis were co-transformed into Y187 strain,and several proteins interacted with HbCoi1 promoter were identified,including DNA binding protein,ribosomal proteins and uncharacterized proteins,which lays a foundation for further study of gene expression of HbCoi1.
2015, 6(3): 261-268.
doi: 10.15886/j.cnki.rdswxb.2015.03.007
Abstract:
Xanthomonas campestris pathovar campestris（Xcc） is the causal agent of black rot disease on cruciferous plants. Xcc deliver many effector proteins into host plant cells via the type Ⅲ secretion system to help its infection and multiplication. In this study,the expression and regulation of XopR gene were analyzed through qRTPCR. The results showed that the XopR gene transcription was regulated by the type Ⅲ regulator of HrpG and HrpX,and the XopR protein secretion was type Ⅲ secretion system dependent,indicating that XopR was a typeⅢ effector protein ofXcc8004. In addition,a XopR gene deletion mutant（ Xcc8004,ΔXopR） was generated,and the disease symptoms caused by ΔXopR strain were decreased on Zhonggan15,Zhonggan21,Zhongbai83 in contrast with WTXcc8004,suggesting that XopR was required for the full virulence ofXcc8004 on Cabbage host plants. Furthermore,XopR was proved to located in plant plasma membrane in Arabidopsis protoplasts cells by XopR-GFP fusion assay. The expression of PTI marker gene FRK1∷LUC was inhibited by XopR protein,which was consistent with the XopR function in Xoo strains.
Xanthomonas campestris pathovar campestris（Xcc） is the causal agent of black rot disease on cruciferous plants. Xcc deliver many effector proteins into host plant cells via the type Ⅲ secretion system to help its infection and multiplication. In this study,the expression and regulation of XopR gene were analyzed through qRTPCR. The results showed that the XopR gene transcription was regulated by the type Ⅲ regulator of HrpG and HrpX,and the XopR protein secretion was type Ⅲ secretion system dependent,indicating that XopR was a typeⅢ effector protein ofXcc8004. In addition,a XopR gene deletion mutant（ Xcc8004,ΔXopR） was generated,and the disease symptoms caused by ΔXopR strain were decreased on Zhonggan15,Zhonggan21,Zhongbai83 in contrast with WTXcc8004,suggesting that XopR was required for the full virulence ofXcc8004 on Cabbage host plants. Furthermore,XopR was proved to located in plant plasma membrane in Arabidopsis protoplasts cells by XopR-GFP fusion assay. The expression of PTI marker gene FRK1∷LUC was inhibited by XopR protein,which was consistent with the XopR function in Xoo strains.
2015, 6(3): 269-272.
doi: 10.15886/j.cnki.rdswxb.2015.03.008
Abstract:
Banana（ Musa acuminata L. AAA group,‘Brazilian’） calli and buds induced from immature male flowers were used as explants,radiated with 60Co-γ ray for mutagenesis and then screened by low temperature selection. Banana plants of two cold tolerant lines（ Kanghan 9 and Kanghan 11） and the control without radiation treatment were determined in terms of starch,total sugar,glucose,fructose and sucrose. The two cold-tolerant banana lines contained highly significantly higher total sugar,sucrose,fructose and glucose in the banana fruit than the control（ P ＜0. 01） and also had higher content of total starch,amylose and amylopectin in the fruit than the control. However,Kanghan 11 had a lower amylose/amylopectin ratio in the fruit than the control.
Banana（ Musa acuminata L. AAA group,‘Brazilian’） calli and buds induced from immature male flowers were used as explants,radiated with 60Co-γ ray for mutagenesis and then screened by low temperature selection. Banana plants of two cold tolerant lines（ Kanghan 9 and Kanghan 11） and the control without radiation treatment were determined in terms of starch,total sugar,glucose,fructose and sucrose. The two cold-tolerant banana lines contained highly significantly higher total sugar,sucrose,fructose and glucose in the banana fruit than the control（ P ＜0. 01） and also had higher content of total starch,amylose and amylopectin in the fruit than the control. However,Kanghan 11 had a lower amylose/amylopectin ratio in the fruit than the control.
2015, 6(3): 273-278,292.
doi: 10.15886/j.cnki.rdswxb.2015.03.009
Abstract:
The liquid samples of water-extract（ 15 ℃）,hot water extract（ 90 ℃）,methanol extract（ 70%）,alcohol extract（ 70%） and acetone extract（ 70%） from the mature leaves of Ilex kudingcha C. J. Tseng were irradiated with 60Co-γ ray at respective doses of 0（ CK）,10,20 and 30 k Gy. The antioxidant activities of the liquid samples were determined via ABTS and DPPH methods and the colors of the liquid samples before and after irradiation were observed and compared. The results showed that the antioxidant activity of the liquid sample of the water extract（ room temperature） was slightly increased after irradiation of 60Co-γ ray. There was,however,no significant difference in the liquid samples extracted with hot water（ 90 ℃）,70% methanol,70% alcohol and 70% acetone. The colors of all the liquid samples extracted with 5 different solvents from the mature leaves in I. kudingcha faded in some degrees. of which the color of the liquid sample extracted with 70% alcohol was the palest,followed by that of the liquid sample extracted with 70% methanol. When the extracts are used for food fresh-keeping and for food or cosmetics preparation,it is recommended to use the extract with 70%methanol as solvent and treat with 60Co-γ ray at the dose of 10 k Gy to ensure the security of food and cosmetics.
The liquid samples of water-extract（ 15 ℃）,hot water extract（ 90 ℃）,methanol extract（ 70%）,alcohol extract（ 70%） and acetone extract（ 70%） from the mature leaves of Ilex kudingcha C. J. Tseng were irradiated with 60Co-γ ray at respective doses of 0（ CK）,10,20 and 30 k Gy. The antioxidant activities of the liquid samples were determined via ABTS and DPPH methods and the colors of the liquid samples before and after irradiation were observed and compared. The results showed that the antioxidant activity of the liquid sample of the water extract（ room temperature） was slightly increased after irradiation of 60Co-γ ray. There was,however,no significant difference in the liquid samples extracted with hot water（ 90 ℃）,70% methanol,70% alcohol and 70% acetone. The colors of all the liquid samples extracted with 5 different solvents from the mature leaves in I. kudingcha faded in some degrees. of which the color of the liquid sample extracted with 70% alcohol was the palest,followed by that of the liquid sample extracted with 70% methanol. When the extracts are used for food fresh-keeping and for food or cosmetics preparation,it is recommended to use the extract with 70%methanol as solvent and treat with 60Co-γ ray at the dose of 10 k Gy to ensure the security of food and cosmetics.
2015, 6(3): 279-284.
doi: 10.15886/j.cnki.rdswxb.2015.03.010
Abstract:
Endophytic bacteria are equally important as mycorrhizal fungi for orchid plant species in the ecological process of seed germination and seedling establishment. To investigate diversity of endophytic bacteria associated with Dendrobium sinense,inhabiting tropical forest in Hainan Island,root samples were collected for bacteria culturing,DNA extraction,16 S rDNA amplification,and sequencing. A total of 130 strains of endophytic bacteria were isolated from the roots of D. sinense in Jianfengling,Bawangling and Diaoluoshan mountains. Phylogenetic analysis of 16 S rDNA sequences revealed that the roots-associated endophytic bacteria community was comprised of 15 species of 7 genera: Bacillus,Burkholderia,Pantoea,Enterobacter,Luteibacter,Serratia and Cedecea. Of these bacteria,Bacillus is the most frequently isolated endophytic bacterium,followed by Enterobacter and Burkholderia. All the Bacillus spp. occurred in the three habitats at a roughly equal frequency. Compositional similarity of endophytic bacterial community associated with D. sinense is highest in between the Bawangling and Diaoluoshan mountains,where similarity is lowest in their environmental factors but highest in their host plant species composition is highest in similarity. This suggests that the difference in host plants is responsible for the difference in endophytic bacterial species composition of the roots of the host plants.
Endophytic bacteria are equally important as mycorrhizal fungi for orchid plant species in the ecological process of seed germination and seedling establishment. To investigate diversity of endophytic bacteria associated with Dendrobium sinense,inhabiting tropical forest in Hainan Island,root samples were collected for bacteria culturing,DNA extraction,16 S rDNA amplification,and sequencing. A total of 130 strains of endophytic bacteria were isolated from the roots of D. sinense in Jianfengling,Bawangling and Diaoluoshan mountains. Phylogenetic analysis of 16 S rDNA sequences revealed that the roots-associated endophytic bacteria community was comprised of 15 species of 7 genera: Bacillus,Burkholderia,Pantoea,Enterobacter,Luteibacter,Serratia and Cedecea. Of these bacteria,Bacillus is the most frequently isolated endophytic bacterium,followed by Enterobacter and Burkholderia. All the Bacillus spp. occurred in the three habitats at a roughly equal frequency. Compositional similarity of endophytic bacterial community associated with D. sinense is highest in between the Bawangling and Diaoluoshan mountains,where similarity is lowest in their environmental factors but highest in their host plant species composition is highest in similarity. This suggests that the difference in host plants is responsible for the difference in endophytic bacterial species composition of the roots of the host plants.
2015, 6(3): 285-292.
doi: 10.15886/j.cnki.rdswxb.2015.03.011
Abstract:
Endophytic bacteria of orchid plants play an important role in orchid life cycle. An attempt was made to inoculate 15 endophytic bacteria isolated from the root of wild plants Phalaenopsis pulcherrima into Phalaenopsis pulcherrima plantlets in vitro for co-culture to analyze their abilities of nitrogen fixation,phosphate solubilization and IAA production. Of the 15 endophytic bacteria,11 strains were found to have a growth-promoting effect on P. pulcherrima plantlets,of which the strain Paenibacillus graminis produced best growth-promoting effect; 9 strains had a potential ability of nitrogen fixation; 10 strains were able to produce IAA,of which the strain Bacillus cereus produced the highest amount of IAA; 7 strains was able to dissolve phosphorus,of which Bacillus megaterium dissolved the highest amount of phosphorus. In addition,endophytic bacteria had a positive correlation between the ability of phosphate-solubilization and the ability of IAA production.
Endophytic bacteria of orchid plants play an important role in orchid life cycle. An attempt was made to inoculate 15 endophytic bacteria isolated from the root of wild plants Phalaenopsis pulcherrima into Phalaenopsis pulcherrima plantlets in vitro for co-culture to analyze their abilities of nitrogen fixation,phosphate solubilization and IAA production. Of the 15 endophytic bacteria,11 strains were found to have a growth-promoting effect on P. pulcherrima plantlets,of which the strain Paenibacillus graminis produced best growth-promoting effect; 9 strains had a potential ability of nitrogen fixation; 10 strains were able to produce IAA,of which the strain Bacillus cereus produced the highest amount of IAA; 7 strains was able to dissolve phosphorus,of which Bacillus megaterium dissolved the highest amount of phosphorus. In addition,endophytic bacteria had a positive correlation between the ability of phosphate-solubilization and the ability of IAA production.
2015, 6(3): 293-297.
doi: 10.15886/j.cnki.rdswxb.2015.03.012
Abstract:
The bio-activity of walnut green husk extracts against the 3rd instar larvae of Spodoptera litura was tested by immersion method in the laboratory. The results indicated that the ethanol extract of walnut green husk had a strong toxic effect on the 3rd instar larvae with the LC50 values of the larvae at day 3 and day 7 being 8. 35g·L-1 and 3. 96 g·L-1 ,respectively. The growth of the 3rd instar larvae of S. litura was also inhibited by the extract at the test concentration of 0. 5- 2. 5 g·L-1 . The weight of the treated larvae increased slowly,the larval development and pupal stage were obviously prolonged,and the pupal weight and pupation rate were significantly lower than those of the control.
The bio-activity of walnut green husk extracts against the 3rd instar larvae of Spodoptera litura was tested by immersion method in the laboratory. The results indicated that the ethanol extract of walnut green husk had a strong toxic effect on the 3rd instar larvae with the LC50 values of the larvae at day 3 and day 7 being 8. 35g·L-1 and 3. 96 g·L-1 ,respectively. The growth of the 3rd instar larvae of S. litura was also inhibited by the extract at the test concentration of 0. 5- 2. 5 g·L-1 . The weight of the treated larvae increased slowly,the larval development and pupal stage were obviously prolonged,and the pupal weight and pupation rate were significantly lower than those of the control.
2015, 6(3): 298-303.
doi: 10.15886/j.cnki.rdswxb.2015.03.013
Abstract:
Isoetes orientalis is a wild national protective endangered aquatic pteridophyte. It is an endemic ancient relict plant inhabited in the middle and lower reaches of Yangtze River. The relationship between pollution of water body and endangerment of I. orientalis had never been reported. Mature I. orientalis plants with similar growth vigor were treated for 2- 14 days with different concentrations（ 5 times,10 times and 20 times）of sewage water to observe the change of 6 physiological indexes of the plants,i. e.,protective enzyme system,osmotic substance,chlorophyll content,malondialdehyde content,relative conductance and photosynthetic rate.I. orientalis was found to have a better tolerance to the stress of the sewage water under 5 and 10 times of the concentration but poor tolerance to the stress under the 20 times of concentration with comparatively obvious physiological injury. According to the sewage stress and the ecological conditions,the authors believe that the sewage water stress might not be the main reason for endangerment of I. orientalis.
Isoetes orientalis is a wild national protective endangered aquatic pteridophyte. It is an endemic ancient relict plant inhabited in the middle and lower reaches of Yangtze River. The relationship between pollution of water body and endangerment of I. orientalis had never been reported. Mature I. orientalis plants with similar growth vigor were treated for 2- 14 days with different concentrations（ 5 times,10 times and 20 times）of sewage water to observe the change of 6 physiological indexes of the plants,i. e.,protective enzyme system,osmotic substance,chlorophyll content,malondialdehyde content,relative conductance and photosynthetic rate.I. orientalis was found to have a better tolerance to the stress of the sewage water under 5 and 10 times of the concentration but poor tolerance to the stress under the 20 times of concentration with comparatively obvious physiological injury. According to the sewage stress and the ecological conditions,the authors believe that the sewage water stress might not be the main reason for endangerment of I. orientalis.
Distribution of Duckweed Community and the Environmental Factors that Affect the Community Structure
2015, 6(3): 304-309,314.
doi: 10.15886/j.cnki.rdswxb.2015.03.014
Abstract:
The duckweeds growing in Hainan Island were collected thrice from May to August 2013,and 34 communities of the duckweeds were sampled from 13 cities/counties of Hainan Province,from which 45 ecotypes of duckweeds were identified under 4 species of duckweeds,Wolffia globosa,Lemna aequinoctialis,Spirodela polyrrhiza and Landoltia punctata. The distribution of three species of the duckweeds except L. punctata was analyzed and the factors of water affecting the community structure,such as p H,N and P content of water on which the duckweeds grew were determined. L. aequinoctialis were found to distribute most widely throughout the whole island; W. globosa were distributed mainly in the north of the Island; S. polyrrhiza and W. globosa were also distributed in different large areas but much less widely than L. aequinoctialis. The duckweeds grew mostly in the quiet and seriously polluted water from sewage treatment plants,waste ponds,etc. The water nutrients and their content were detected to analyze their relationship with the growth of each species of duckweeds by using one-way ANOVA and one-way MANOVA. Results revealed no obvious relationship between the distribution of duckweeds and their growth water environment,but only an occasional phenomenon. Moreover,the duckweeds were observed under a simulated natural growth environment to see the impact of temperature and water nutrients on the growth of the duckweeds and the duckweed community structure,and the results showed that the temperature had a greater impact on the duckweed community structure than the water nutrients.
The duckweeds growing in Hainan Island were collected thrice from May to August 2013,and 34 communities of the duckweeds were sampled from 13 cities/counties of Hainan Province,from which 45 ecotypes of duckweeds were identified under 4 species of duckweeds,Wolffia globosa,Lemna aequinoctialis,Spirodela polyrrhiza and Landoltia punctata. The distribution of three species of the duckweeds except L. punctata was analyzed and the factors of water affecting the community structure,such as p H,N and P content of water on which the duckweeds grew were determined. L. aequinoctialis were found to distribute most widely throughout the whole island; W. globosa were distributed mainly in the north of the Island; S. polyrrhiza and W. globosa were also distributed in different large areas but much less widely than L. aequinoctialis. The duckweeds grew mostly in the quiet and seriously polluted water from sewage treatment plants,waste ponds,etc. The water nutrients and their content were detected to analyze their relationship with the growth of each species of duckweeds by using one-way ANOVA and one-way MANOVA. Results revealed no obvious relationship between the distribution of duckweeds and their growth water environment,but only an occasional phenomenon. Moreover,the duckweeds were observed under a simulated natural growth environment to see the impact of temperature and water nutrients on the growth of the duckweeds and the duckweed community structure,and the results showed that the temperature had a greater impact on the duckweed community structure than the water nutrients.
2015, 6(3): 310-314.
doi: 10.15886/j.cnki.rdswxb.2015.03.015
Abstract:
Camellia oleosa Rehd. in Hainan Province is an evergreen shrub or small tree; its bark is smooth with gray brown; the twigs have some shags,dark green; leaves simple,alternate,leathery,smooth,ovate oval or oblong,apex acute,base cuneate,about 5- 7cm,margin serrate; the petioles are 4- 8 mm; the flowers are bisexual,white,and terminal,capsular; the seeds are brown and triangular ovate,hemispherical or spherical with naps. Pollen morphology of C. oleosa Rehd. collected from Hainan Province was observed by using Scanning Electron Microscope（ SEM）. C. oleosa Rehd. in Hainan Province had similar pollen morphology to the species of the genus Camellia. The pollens were generally prolate spheroidal with three colporates,and their exine sculptures were foveolate-reticulate. Moreover,the pollens had similar shape,size and exine sculpture to those of sect. Camellia（ L.） Dyer in Hook,which indicated that this species had close phylogenetic relationship with some species of the sect. Camellia of the genus Camellia. However,the pollen morphology was quite different from the sect. Paracamellia. The pollen size was negatively correlated with fruit weight,but not correlated with the fruit shape index and oil production.
Camellia oleosa Rehd. in Hainan Province is an evergreen shrub or small tree; its bark is smooth with gray brown; the twigs have some shags,dark green; leaves simple,alternate,leathery,smooth,ovate oval or oblong,apex acute,base cuneate,about 5- 7cm,margin serrate; the petioles are 4- 8 mm; the flowers are bisexual,white,and terminal,capsular; the seeds are brown and triangular ovate,hemispherical or spherical with naps. Pollen morphology of C. oleosa Rehd. collected from Hainan Province was observed by using Scanning Electron Microscope（ SEM）. C. oleosa Rehd. in Hainan Province had similar pollen morphology to the species of the genus Camellia. The pollens were generally prolate spheroidal with three colporates,and their exine sculptures were foveolate-reticulate. Moreover,the pollens had similar shape,size and exine sculpture to those of sect. Camellia（ L.） Dyer in Hook,which indicated that this species had close phylogenetic relationship with some species of the sect. Camellia of the genus Camellia. However,the pollen morphology was quite different from the sect. Paracamellia. The pollen size was negatively correlated with fruit weight,but not correlated with the fruit shape index and oil production.
2015, 6(3): 315-319.
doi: 10.15886/j.cnki.rdswxb.2015.03.016
Abstract:
Bougainvillea is one of the wonderful world old flowers with colorful bracts that are perfect for landscaping. A flowering observation and monitoring was conducted in 45 Bougainvillea varieties cultivated in Xiamen,Fujian,China to have a good picture of their flowering characteristics. These cultivars were categorized based on observations into early,middle and late cultivars with single or multiple flowering periods,which will provide scientific and practical guidance for landscaping and greening in urban areas.
Bougainvillea is one of the wonderful world old flowers with colorful bracts that are perfect for landscaping. A flowering observation and monitoring was conducted in 45 Bougainvillea varieties cultivated in Xiamen,Fujian,China to have a good picture of their flowering characteristics. These cultivars were categorized based on observations into early,middle and late cultivars with single or multiple flowering periods,which will provide scientific and practical guidance for landscaping and greening in urban areas.
2015, 6(3): 320-324.
doi: 10.15886/j.cnki.rdswxb.2015.03.017
Abstract:
Eight varieties of okra（ Abelmoschus esculentus Linn.） were collected and cultivated for demonstration and experiment to screen out good okra cultivars suitable for cultivation in Changsha city,Hunan Province. They were compared and evaluated in terms of agronomic traits,yield and stress tolerance in the field experiment.Each okra variety was harvested about 90- 116 days after planting. Of all the okra varieties,the variety zx-2 had the longest duration of growth and harvest,which were 163 and 116 days,respectively; the varieties zx-1 and zx-2 showed the best characteristics of plant height and yield,which were 178. 67 and 165. 67 cm,25 320. 3and 22 465. 5 kg·hm-2,respectively. In addition,the variety zx-2 had a better young fruit shape than other varieties and its fruit shape was round and pointed and long and thin. Comprehensive evaluation showed that the variety zx-2 was high in stress tolerance,pod yield and pod quality. It was recommended to expand cultivation of this variety in Changsha city.
Eight varieties of okra（ Abelmoschus esculentus Linn.） were collected and cultivated for demonstration and experiment to screen out good okra cultivars suitable for cultivation in Changsha city,Hunan Province. They were compared and evaluated in terms of agronomic traits,yield and stress tolerance in the field experiment.Each okra variety was harvested about 90- 116 days after planting. Of all the okra varieties,the variety zx-2 had the longest duration of growth and harvest,which were 163 and 116 days,respectively; the varieties zx-1 and zx-2 showed the best characteristics of plant height and yield,which were 178. 67 and 165. 67 cm,25 320. 3and 22 465. 5 kg·hm-2,respectively. In addition,the variety zx-2 had a better young fruit shape than other varieties and its fruit shape was round and pointed and long and thin. Comprehensive evaluation showed that the variety zx-2 was high in stress tolerance,pod yield and pod quality. It was recommended to expand cultivation of this variety in Changsha city.
2015, 6(3): 325-328.
doi: 10.15886/j.cnki.rdswxb.2015.03.018
Abstract:
Artemisinin was extracted from mature leaves of Artemisia annua L. by using a rotary evaporation method or a vacuum concentration method to establish an effective,simple method for artemisinin extraction.The absorbance of artemisinin was determined at the wavelength of 292 nm by using ultraviolet spectrophotometer. The rotary evaporation method extracted artemisinin at an average recovery rate of 92. 18% with the RSD being 0. 91%,and the vacuum concentration method extracted artemisinin at an average recovery rate of 92. 90%with the RSD being 0. 77%. These two methods had respective RSDs of 1. 11% and 1. 61% in the precision test,1. 53% and 1. 70% in a stability test,and 0. 76% and 1. 03% in the repeatability test. It is concluded that the vacuum concentration method was simpler and more rapid and feasible than the rotary evaporation method for extraction of artemisinin from the leaves of A. annua L.
Artemisinin was extracted from mature leaves of Artemisia annua L. by using a rotary evaporation method or a vacuum concentration method to establish an effective,simple method for artemisinin extraction.The absorbance of artemisinin was determined at the wavelength of 292 nm by using ultraviolet spectrophotometer. The rotary evaporation method extracted artemisinin at an average recovery rate of 92. 18% with the RSD being 0. 91%,and the vacuum concentration method extracted artemisinin at an average recovery rate of 92. 90%with the RSD being 0. 77%. These two methods had respective RSDs of 1. 11% and 1. 61% in the precision test,1. 53% and 1. 70% in a stability test,and 0. 76% and 1. 03% in the repeatability test. It is concluded that the vacuum concentration method was simpler and more rapid and feasible than the rotary evaporation method for extraction of artemisinin from the leaves of A. annua L.
2015, 6(3): 329-334.
doi: 10.15886/j.cnki.rdswxb.2015.03.019
Abstract:
Stems of two cassava varieties SC5 and SC9 were treated with pregelatinized oxidized cassava starch（ Treatment 1）,pregelatinized oxidized cassava meal（ Treatment 2） and blank as control,and stored under low temperature（ 0 ℃）. The Low Field Nuclear Magnetic Resonance Imaging（ LF-NMRI） method was used to determine the water states and water mobility of the treated cassava stems in view of exploring the effects of water states and water mobility on the survival rate of the treated cassava stems stored under low temperature. Observations showed that free water was the main state of water in the treated cassava stems,accounting for 55%-75%,and mainly distributed in the phloem of the cassava stems. The two treatments improved the survival rate of the cassava stems stored under low temperature as compared to the control,and Treatment 1 gave a higher survival rate of the cassava stems than Treatment 2. At the same time,the SC9 had a higher survival rate than the SC5 after low temperature storage. It could be concluded that the SC9 was higher in tolerance to low temperature than the SC5.
Stems of two cassava varieties SC5 and SC9 were treated with pregelatinized oxidized cassava starch（ Treatment 1）,pregelatinized oxidized cassava meal（ Treatment 2） and blank as control,and stored under low temperature（ 0 ℃）. The Low Field Nuclear Magnetic Resonance Imaging（ LF-NMRI） method was used to determine the water states and water mobility of the treated cassava stems in view of exploring the effects of water states and water mobility on the survival rate of the treated cassava stems stored under low temperature. Observations showed that free water was the main state of water in the treated cassava stems,accounting for 55%-75%,and mainly distributed in the phloem of the cassava stems. The two treatments improved the survival rate of the cassava stems stored under low temperature as compared to the control,and Treatment 1 gave a higher survival rate of the cassava stems than Treatment 2. At the same time,the SC9 had a higher survival rate than the SC5 after low temperature storage. It could be concluded that the SC9 was higher in tolerance to low temperature than the SC5.
2015, 6(3): 335-346.
doi: 10.15886/j.cnki.rdswxb.2015.03.020
Abstract:
Acaulospora is an important genus of arbuscular mycorrhizal fungi in the family Acaulosporaceae.Fungi of the Acaulosporaceae are distributed widely in different terrestrial ecological systems and their family has two genera: Acaulospora and Kuklospora. In Acaulospora about 40 species have been recorded in the world. The morphological characteristics and distribution of the species in the genus Acaulospora recorded in China were described.
Acaulospora is an important genus of arbuscular mycorrhizal fungi in the family Acaulosporaceae.Fungi of the Acaulosporaceae are distributed widely in different terrestrial ecological systems and their family has two genera: Acaulospora and Kuklospora. In Acaulospora about 40 species have been recorded in the world. The morphological characteristics and distribution of the species in the genus Acaulospora recorded in China were described.
2015, 6(3): 347-352.
doi: 10.15886/j.cnki.rdswxb.2015.03.021
Abstract:
Tapping Panel Dryness（ TPD） of rubber tree（ Hevea brasiliensis） is a serious threat to rubber industry. Research in TPD has been made for about hundred years since TPD occurred,but no solution to TPD is available. Numerous molecular research activities in TPD have been conducted in recent years to elucidate the mechanism of TPD occcurrence. Advances in study of genes and proteins related to TPD of rubber tree via gene cloning,genomics and proteomics in recent years were reviewed.
Tapping Panel Dryness（ TPD） of rubber tree（ Hevea brasiliensis） is a serious threat to rubber industry. Research in TPD has been made for about hundred years since TPD occurred,but no solution to TPD is available. Numerous molecular research activities in TPD have been conducted in recent years to elucidate the mechanism of TPD occcurrence. Advances in study of genes and proteins related to TPD of rubber tree via gene cloning,genomics and proteomics in recent years were reviewed.
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