2018 Vol. 9, No. 3
2018, 9(3): 267-273,338.
doi: 10.15886/j.cnki.rdswxb.2018.03.001
Abstract
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Abstract:
Zebrafish（ Danino rerio AB） was treated with pleocidin and spinetoram at different concentrations(120,151,190,240,302,380,480 mg·L-1 for pleocidin,and 0. 6,1. 8,5. 45,16. 4 and 49. 4 mg·L-1 for spinetoram) to observe the effect of the two chemicals on the embryo development of zebrafish. The test followed strictly the OECD guidelines for testing of fish embryo acute toxicity（ FET）. The results showed that the median lethal concentration（ LC50） for zebrafish embryos exposed to pleocidin after 96 h of fertilization was 242. 27 mg·L-1,and 9. 713 mg·L-1 when exposed to spinetoram. Pleocidin and spinetoram had no dosage-response relationships in the frequency of spontaneous movement in 1 min after 24 h of fertilization,the frequency of heart beat in 20 s after 48 h of fertilization,and the body length after 96 h of pollination. Pleocidin and spinetoram showed a dosage-response relationship in the frequency of spinal curvature after 72 h of fertilization. These two chemicals were all low in toxicity,and in high concentrations,pleocidin is more friendly to Zebrafish than spinetoram.
Zebrafish（ Danino rerio AB） was treated with pleocidin and spinetoram at different concentrations(120,151,190,240,302,380,480 mg·L-1 for pleocidin,and 0. 6,1. 8,5. 45,16. 4 and 49. 4 mg·L-1 for spinetoram) to observe the effect of the two chemicals on the embryo development of zebrafish. The test followed strictly the OECD guidelines for testing of fish embryo acute toxicity（ FET）. The results showed that the median lethal concentration（ LC50） for zebrafish embryos exposed to pleocidin after 96 h of fertilization was 242. 27 mg·L-1,and 9. 713 mg·L-1 when exposed to spinetoram. Pleocidin and spinetoram had no dosage-response relationships in the frequency of spontaneous movement in 1 min after 24 h of fertilization,the frequency of heart beat in 20 s after 48 h of fertilization,and the body length after 96 h of pollination. Pleocidin and spinetoram showed a dosage-response relationship in the frequency of spinal curvature after 72 h of fertilization. These two chemicals were all low in toxicity,and in high concentrations,pleocidin is more friendly to Zebrafish than spinetoram.
2018, 9(3): 274-280.
doi: 10.15886/j.cnki.rdswxb.2018.03.002
Abstract:
An attempt was made to observe the effect of rutile titanium dioxide nanoparticles（ TiO2 NPs） on oxidative damage of zebrafish（ Danio rerio）. Adult zebrafish was exposed to TiO2 NPs at the concentrations of 10,50 and 100 mg·L-1 for 10 days with the exposure to the bulk TiO2 (100 mg·L-1) as the control. Twenty adult zebrafish were treated at each concentration,and six fish treated were caught to analyze their changes of superoxide dismutase（SOD） activities in the gills,livers and guts. The SOD was used as a bimarker,and the SOD changes at the protein and molecular level were analyzed by using the enzyme-linked immunosorbent assay（ ELISA） and real-time quantitative PCR（ Q-PCR）. Results showed that the TiO2 NPs decreased the SOD activity in the gill and liver tissues of zebrafish,but had little effect on the SOD activity in the gut tissue. The sod gene expression was up-regulated by 2-3 times in the three tissues. It is concluded that long-term exposure of zebrafish to TiO2 NPs can give an impact on the SOD level within the body of zebrafish and cause oxidative damage to gills and livers of zebrafish.
An attempt was made to observe the effect of rutile titanium dioxide nanoparticles（ TiO2 NPs） on oxidative damage of zebrafish（ Danio rerio）. Adult zebrafish was exposed to TiO2 NPs at the concentrations of 10,50 and 100 mg·L-1 for 10 days with the exposure to the bulk TiO2 (100 mg·L-1) as the control. Twenty adult zebrafish were treated at each concentration,and six fish treated were caught to analyze their changes of superoxide dismutase（SOD） activities in the gills,livers and guts. The SOD was used as a bimarker,and the SOD changes at the protein and molecular level were analyzed by using the enzyme-linked immunosorbent assay（ ELISA） and real-time quantitative PCR（ Q-PCR）. Results showed that the TiO2 NPs decreased the SOD activity in the gill and liver tissues of zebrafish,but had little effect on the SOD activity in the gut tissue. The sod gene expression was up-regulated by 2-3 times in the three tissues. It is concluded that long-term exposure of zebrafish to TiO2 NPs can give an impact on the SOD level within the body of zebrafish and cause oxidative damage to gills and livers of zebrafish.
2018, 9(3): 281-286.
doi: 10.15886/j.cnki.rdswxb.2018.03.003
Abstract:
Litopenaeus vannamei weighing（ 0. 163 ± 0. 07） g were cultured with feed added with 0. 2%,0. 5% and 1. 0% of microbial antimicrobial peptide S200（ AMP S200）. After 12 weeks,the L. vannamei were inoculated with white spot syndrome virus（ WSSRV）,Vibrio harveyi and Vibrio parahaemolyticus,respectively and cultured for 16 weeks. The results showed that the addition of 0. 2% and 0. 5% of the AMP S200 in the feed significantly increased the survival rate and the activity of lysozyme and superoxide dismutase of L. vannamei challenged. When the AMP S200 was added at a rate of 0. 2% into the feed,the cumulative mortality rate of L.vannamei challenged with V. parahaemolyticus was 10. 0%,the lowest. When the feed was added with AMP S200 at a rate of 0. 5%,the L. vannamei showed cumulative mortality rates of 13. 0% and 20. 0%,respectively when challenged with V. harveyi and WSSV,and 40. 0% when challenged with V. parahaemolyticus. The activities of lysozyme and superoxide dismutase were 44. 35 U · mg-1 prot and 60. 8 U · mg-1 prot,respectively,which were significantly higher than those of the control group（ P ＜ 0. 05）. When the feed was added with AMP S200 at a rate of 1. 0%,the cumulative mortality rates of L. vannamei challenged with WSSV,V. harveyi,and V. parahaemolyticus were 53. 33%,20. 0% and 40. 0%,respectively. The activities of lysozyme and superoxide dismutase were 9. 8 U·mg-1 prot and 50. 17 U·mg-1 prot,respectively. Compared with the group treated with the feed added with AMP S200 at a rate of 0. 5%,all the figures were low in the group treated with the AMP S200 at a rate of 1. 0% except for the cumulative mortality rate of L. vannamei challenged with V. parahaemolyticus（ 40. 0%）. The higher rate of AMP S200 showed a certain negative effect on the virus resistance of L.vannamei. Compared with the control groups,the L. vannamei treated with AMP S200 at a higher ratewas not significantly different in lysozyme activity（ P ＞ 0. 05）. The cumulative mortality rates of L. vannamei challenged with V. parahaemolyticus and WSSV were significantly higher than those of the control groups（ P ＜ 0. 05）. These results showed that adding of an appropriate amount of AMP S200 in feed can increase the survival rate and the activities of superoxide dismutase and lysozyme of L. vannamei challenged with WSSV,V. harveyi,and V. parahaemolyticus,and improve the immunity of L. vannamei,contributing to the success of L. vannamei culture.
Litopenaeus vannamei weighing（ 0. 163 ± 0. 07） g were cultured with feed added with 0. 2%,0. 5% and 1. 0% of microbial antimicrobial peptide S200（ AMP S200）. After 12 weeks,the L. vannamei were inoculated with white spot syndrome virus（ WSSRV）,Vibrio harveyi and Vibrio parahaemolyticus,respectively and cultured for 16 weeks. The results showed that the addition of 0. 2% and 0. 5% of the AMP S200 in the feed significantly increased the survival rate and the activity of lysozyme and superoxide dismutase of L. vannamei challenged. When the AMP S200 was added at a rate of 0. 2% into the feed,the cumulative mortality rate of L.vannamei challenged with V. parahaemolyticus was 10. 0%,the lowest. When the feed was added with AMP S200 at a rate of 0. 5%,the L. vannamei showed cumulative mortality rates of 13. 0% and 20. 0%,respectively when challenged with V. harveyi and WSSV,and 40. 0% when challenged with V. parahaemolyticus. The activities of lysozyme and superoxide dismutase were 44. 35 U · mg-1 prot and 60. 8 U · mg-1 prot,respectively,which were significantly higher than those of the control group（ P ＜ 0. 05）. When the feed was added with AMP S200 at a rate of 1. 0%,the cumulative mortality rates of L. vannamei challenged with WSSV,V. harveyi,and V. parahaemolyticus were 53. 33%,20. 0% and 40. 0%,respectively. The activities of lysozyme and superoxide dismutase were 9. 8 U·mg-1 prot and 50. 17 U·mg-1 prot,respectively. Compared with the group treated with the feed added with AMP S200 at a rate of 0. 5%,all the figures were low in the group treated with the AMP S200 at a rate of 1. 0% except for the cumulative mortality rate of L. vannamei challenged with V. parahaemolyticus（ 40. 0%）. The higher rate of AMP S200 showed a certain negative effect on the virus resistance of L.vannamei. Compared with the control groups,the L. vannamei treated with AMP S200 at a higher ratewas not significantly different in lysozyme activity（ P ＞ 0. 05）. The cumulative mortality rates of L. vannamei challenged with V. parahaemolyticus and WSSV were significantly higher than those of the control groups（ P ＜ 0. 05）. These results showed that adding of an appropriate amount of AMP S200 in feed can increase the survival rate and the activities of superoxide dismutase and lysozyme of L. vannamei challenged with WSSV,V. harveyi,and V. parahaemolyticus,and improve the immunity of L. vannamei,contributing to the success of L. vannamei culture.
2018, 9(3): 287-294.
doi: 10.15886/j.cnki.rdswxb.2018.03.004
Abstract:
In order to explore the effect of tidal water flow on water purification in recirculating aquaculture systems,biofilters in recirculating aquaculture systems with tidal water flow and spill water flow setups were compared and analyzed by using the National Standard for Determination of Water Quality to observe their effect on removal of nitrogen and phosphorus in the water of the fish tank. The experimental results of ammonia nitrogen load showed that the concentration of NH4+-N in the water was reduced from 1. 11 mg·L-1 to below 0. 01 mg·L-1 in 12 d in the tidal aquaponics,and in 15 d in the spill aquaponics. There was no much difference in removal speed of PO43--P between the tidal and the spill aquaponics,and the highest concentration of NO2--N was 0. 05 mg·L-1 in the tidal aquaponics,and 0. 22 mg·L-1 in the spill aquaponics during the experiment. It is hence concluded that the tidal recirculating aquaculture system is better than the spill one in the removal of NH4+-N and NO2--N.
In order to explore the effect of tidal water flow on water purification in recirculating aquaculture systems,biofilters in recirculating aquaculture systems with tidal water flow and spill water flow setups were compared and analyzed by using the National Standard for Determination of Water Quality to observe their effect on removal of nitrogen and phosphorus in the water of the fish tank. The experimental results of ammonia nitrogen load showed that the concentration of NH4+-N in the water was reduced from 1. 11 mg·L-1 to below 0. 01 mg·L-1 in 12 d in the tidal aquaponics,and in 15 d in the spill aquaponics. There was no much difference in removal speed of PO43--P between the tidal and the spill aquaponics,and the highest concentration of NO2--N was 0. 05 mg·L-1 in the tidal aquaponics,and 0. 22 mg·L-1 in the spill aquaponics during the experiment. It is hence concluded that the tidal recirculating aquaculture system is better than the spill one in the removal of NH4+-N and NO2--N.
2018, 9(3): 295-301.
doi: 10.15886/j.cnki.rdswxb.2018.03.005
Abstract:
As bacterial unique immune system, clustered regularly interspaced short palindromic repeats（ CRISPR）/Cas9 is the most effective gene editing tool at present. Outer membrane vesicles（ OMVs） are the physiological structures of active secretion and absorption of bacteria,and have the ability to carry DNA,protein and some other substances. To investigate the possibility of OMVs transporting CRISPR/Cas9 and eliminating pathogenic bacteria,the plasmid pCas9 was reconstructed to develop shuttle plasmid pCas9-2. 0（ which can be replicated in E. coli and Streptococcus agalactiae or Group B Streptococcus,GBS）,and p Cas9-cfb( which is derived by inserting crRNA targeting cfb gene in GBS E0. The E. coli X6097（ Δasd） was used for harboring pCas9-2. 0 or pCas9-cfb. The OMVs of recombinant X6097 were extracted,purified and observed by electron microscope. The pCas9-2. 0 or pCas9-cfb was detected from OMVs by PCR. Recombinant X6097 and GBS E0 strains were mixed and co-cultured,and finally counted on BHI medium by using the colony count method. The results showed that the OMVs were secreted by the recombinant X6097 as a carrier for shipping the plasmid from the X6097 to the GBS E0. The secretion and transfer efficiency of OMVs were enhanced by prolonging co-culture time with low-level kanamycin. The GBS E0 was killed by absorbing pCas9-cfb. Compared with the traditional prophylactic vaccine,this study provides a new research strategy for the control of pathogenic bacteria in natural environment. Compared with the current phage delivery systems,this method is more convenient and lower in cost. In addition,this study developed a new plasmid transformation method for some strains that are hard to be electroporated or some labs without electroporation apparatus.
As bacterial unique immune system, clustered regularly interspaced short palindromic repeats（ CRISPR）/Cas9 is the most effective gene editing tool at present. Outer membrane vesicles（ OMVs） are the physiological structures of active secretion and absorption of bacteria,and have the ability to carry DNA,protein and some other substances. To investigate the possibility of OMVs transporting CRISPR/Cas9 and eliminating pathogenic bacteria,the plasmid pCas9 was reconstructed to develop shuttle plasmid pCas9-2. 0（ which can be replicated in E. coli and Streptococcus agalactiae or Group B Streptococcus,GBS）,and p Cas9-cfb( which is derived by inserting crRNA targeting cfb gene in GBS E0. The E. coli X6097（ Δasd） was used for harboring pCas9-2. 0 or pCas9-cfb. The OMVs of recombinant X6097 were extracted,purified and observed by electron microscope. The pCas9-2. 0 or pCas9-cfb was detected from OMVs by PCR. Recombinant X6097 and GBS E0 strains were mixed and co-cultured,and finally counted on BHI medium by using the colony count method. The results showed that the OMVs were secreted by the recombinant X6097 as a carrier for shipping the plasmid from the X6097 to the GBS E0. The secretion and transfer efficiency of OMVs were enhanced by prolonging co-culture time with low-level kanamycin. The GBS E0 was killed by absorbing pCas9-cfb. Compared with the traditional prophylactic vaccine,this study provides a new research strategy for the control of pathogenic bacteria in natural environment. Compared with the current phage delivery systems,this method is more convenient and lower in cost. In addition,this study developed a new plasmid transformation method for some strains that are hard to be electroporated or some labs without electroporation apparatus.
2018, 9(3): 302-311.
doi: 10.15886/j.cnki.rdswxb.2018.03.006
Abstract:
Recent studies have revealed that plant GSK3 proteins are actively implicated in hormonal signalling networks during development as well as in biotic and abiotic stress responses. The GSK in rubber tree function in stress tolerance is unknown. Rubber trees of clone CATAS7-33-97 were treated with mechanical wounding（ without latex flow）,tapping（ with latex flow） with the untreated as the control,and then tapped after 2 hr,6 hr and 1 d,3 d,5 d,7 d of treatment to extract the total RNA from the latex sampled,and the full length cDNA of HbGSK1（ GenBank: JN835185. 1） was amplified from the cDNA library in the latex. It was 1 506 base pairs（ bp）in length,containing a 1 230 bp open reading frame（ ORF）,encoding 409 amino acid residues with a predicted molecular mass of 46. 35 ku and a pI of 8. 69. Real-time PCR analysis showed that the expression of HbGSK1 was upregulated by mechanical wounding（ without latex flow）. However,the expression of HbGSK1 was downregulated by first tapping,upregulated by second tapping,and then recovered to the level of that of the untreated control. The tapping had higher influence on HbGSK1 expression than the mechanical wounding. Furthermore,the expression patterns of HbGSK1 in the latex was regulated by biological clock. The change of HbGSK1 transcript levels in the latex indicated that the HbGSK1 protein was involved in abiotic stress responses of rubber tree.
Recent studies have revealed that plant GSK3 proteins are actively implicated in hormonal signalling networks during development as well as in biotic and abiotic stress responses. The GSK in rubber tree function in stress tolerance is unknown. Rubber trees of clone CATAS7-33-97 were treated with mechanical wounding（ without latex flow）,tapping（ with latex flow） with the untreated as the control,and then tapped after 2 hr,6 hr and 1 d,3 d,5 d,7 d of treatment to extract the total RNA from the latex sampled,and the full length cDNA of HbGSK1（ GenBank: JN835185. 1） was amplified from the cDNA library in the latex. It was 1 506 base pairs（ bp）in length,containing a 1 230 bp open reading frame（ ORF）,encoding 409 amino acid residues with a predicted molecular mass of 46. 35 ku and a pI of 8. 69. Real-time PCR analysis showed that the expression of HbGSK1 was upregulated by mechanical wounding（ without latex flow）. However,the expression of HbGSK1 was downregulated by first tapping,upregulated by second tapping,and then recovered to the level of that of the untreated control. The tapping had higher influence on HbGSK1 expression than the mechanical wounding. Furthermore,the expression patterns of HbGSK1 in the latex was regulated by biological clock. The change of HbGSK1 transcript levels in the latex indicated that the HbGSK1 protein was involved in abiotic stress responses of rubber tree.
2018, 9(3): 312-319.
doi: 10.15886/j.cnki.rdswxb.2018.03.007
Abstract:
The RNA-Seq sequencing technique was used to sequence the root system of pitaya under flooding stress,and the difference of gene expression between the flooded group and the control group was compared. The expression characteristics of the differentially expressed genes were analyzed and verified by qRT-PCR to explore the molecular mechanism of flooding stress and explore genes related to flooding tolerance. The results showed that there were 1 481 differentially expressed genes in the root system of pitaya under flooding stress,including 925 up-regulated genes and 556 down-regulated genes. Their functions were mainly enriched in sugar metabolism,carbon metabolism,nitrogen metabolism,ethanol metabolism,amino acid biosynthesis,phenylalanine metabolism,plant hormone signal transduction and so on. It can be seen that flooding stress has a great effect on the basic metabolism of pitaya root,but the root system of pitaya can provide the energy required for the survival of pitaya through glycolysis,ethanol fermentation and alanine fermentation to reduce the adverse effects of flooding stress on pitaya. And flooding stress induced ethylene synthesis to regulate the stress response of pitaya so that the pitaya showed a certain tolerance to flooding stress.
The RNA-Seq sequencing technique was used to sequence the root system of pitaya under flooding stress,and the difference of gene expression between the flooded group and the control group was compared. The expression characteristics of the differentially expressed genes were analyzed and verified by qRT-PCR to explore the molecular mechanism of flooding stress and explore genes related to flooding tolerance. The results showed that there were 1 481 differentially expressed genes in the root system of pitaya under flooding stress,including 925 up-regulated genes and 556 down-regulated genes. Their functions were mainly enriched in sugar metabolism,carbon metabolism,nitrogen metabolism,ethanol metabolism,amino acid biosynthesis,phenylalanine metabolism,plant hormone signal transduction and so on. It can be seen that flooding stress has a great effect on the basic metabolism of pitaya root,but the root system of pitaya can provide the energy required for the survival of pitaya through glycolysis,ethanol fermentation and alanine fermentation to reduce the adverse effects of flooding stress on pitaya. And flooding stress induced ethylene synthesis to regulate the stress response of pitaya so that the pitaya showed a certain tolerance to flooding stress.
2018, 9(3): 320-327.
doi: 10.15886/j.cnki.rdswxb.2018.03.008
Abstract:
Although pitaya（ Hylocereus undatus） has a good drought tolerance,drought stress could result in reduced production,low quality,and even failure in bearing fruit of pitaya. The pitaya Dahong was used as the experimental material,and a new generation of high-throughput sequencing technology（ RNA-Seq） was used to compare the differences in the root and stem of the pitaya between the treatment group and the control group. We screened differentially expressed genes（ DEGs） from the root and stem,and verified the expression of the screened genes by qRT-PCR. A total of 194 DEGs were produced from CR-VS-DR,including 70 up-regulated expression genes and 124 down-regulated expression genes which responded to drought stress. From CS-VS-DS,21 DEGs were obtained,including 12 up-regulated expression genes and 9 down-regulated expression genes which responded to drought stress. The sereened differentially expressed genes were mainly concentrated in the process of tyrosine metabolism,secondary metabolite biosynthesis,glycolysis/glycoheterosis,and carbon metabolism. It showed that the pitaya was mainly adapted to drought stress by adjusting its basic metabolism,and the tyrosine metabolism may play an important role in the drought resistance of the pitaya.
Although pitaya（ Hylocereus undatus） has a good drought tolerance,drought stress could result in reduced production,low quality,and even failure in bearing fruit of pitaya. The pitaya Dahong was used as the experimental material,and a new generation of high-throughput sequencing technology（ RNA-Seq） was used to compare the differences in the root and stem of the pitaya between the treatment group and the control group. We screened differentially expressed genes（ DEGs） from the root and stem,and verified the expression of the screened genes by qRT-PCR. A total of 194 DEGs were produced from CR-VS-DR,including 70 up-regulated expression genes and 124 down-regulated expression genes which responded to drought stress. From CS-VS-DS,21 DEGs were obtained,including 12 up-regulated expression genes and 9 down-regulated expression genes which responded to drought stress. The sereened differentially expressed genes were mainly concentrated in the process of tyrosine metabolism,secondary metabolite biosynthesis,glycolysis/glycoheterosis,and carbon metabolism. It showed that the pitaya was mainly adapted to drought stress by adjusting its basic metabolism,and the tyrosine metabolism may play an important role in the drought resistance of the pitaya.
2018, 9(3): 328-332.
doi: 10.15886/j.cnki.rdswxb.2018.03.009
Abstract:
The annual semi-lignified branches of Rhododendron hainanense were selected as cuttings,and an orthogonal experiment was arranged for culture of the cuttings on different substratesto analyze the effects of treatment time and concentrations of IBA and NAA on the cutting propagation of R. hainanense in Substrate 1（ peat:coco coir∶ perlite = 1∶ 1∶ 1） and Substrate 2（ garden soil: coco coir∶ perlite = 1∶ 1∶ 1）,in order to screen the best treatment combination that improved rooting rate and the health of root system. The results showed that hormones had significant influence on rooting rate,of which IBA was the better hormone for root induction. Cuttings,when soaked in 600 mg·L-1 IBA for 600 s and then inserted into the Substrate 2 produced the highest rooting rate（ up to 90. 0%） with the longest adventitious root being up to 2. 1 cm. Substrates had significant influence on the length of adventitious roots,Cuttings,when soaked in 600 mg·L-1 NAA for 10 s and inserted into the Substrate 2,produced an rooting rate of up to 80. 0% with the longest adventitious roots of up to 3. 1 cm. All the results showed that cuttings improved the rooting rate and the health of root system effectively when soaked in 600 mg·L-1 IBA for 600 s and inserted into the Substrate 2.
The annual semi-lignified branches of Rhododendron hainanense were selected as cuttings,and an orthogonal experiment was arranged for culture of the cuttings on different substratesto analyze the effects of treatment time and concentrations of IBA and NAA on the cutting propagation of R. hainanense in Substrate 1（ peat:coco coir∶ perlite = 1∶ 1∶ 1） and Substrate 2（ garden soil: coco coir∶ perlite = 1∶ 1∶ 1）,in order to screen the best treatment combination that improved rooting rate and the health of root system. The results showed that hormones had significant influence on rooting rate,of which IBA was the better hormone for root induction. Cuttings,when soaked in 600 mg·L-1 IBA for 600 s and then inserted into the Substrate 2 produced the highest rooting rate（ up to 90. 0%） with the longest adventitious root being up to 2. 1 cm. Substrates had significant influence on the length of adventitious roots,Cuttings,when soaked in 600 mg·L-1 NAA for 10 s and inserted into the Substrate 2,produced an rooting rate of up to 80. 0% with the longest adventitious roots of up to 3. 1 cm. All the results showed that cuttings improved the rooting rate and the health of root system effectively when soaked in 600 mg·L-1 IBA for 600 s and inserted into the Substrate 2.
2018, 9(3): 333-338.
doi: 10.15886/j.cnki.rdswxb.2018.03.010
Abstract:
The stem of Cerasus serrulata var. lannesiana ‘Sirotae’with buds were used as explants,sterilized and cultured on mediums with various combinations and concentrations of plant growth regulators for rapid progagation. The explants were cultured in a medium of MS + 6-BA 1. 0 mg·L-1+ NAA 0. 1 mg·L-1 to induce shoots. The shoots were then subcultured in the medium of MS + 6-BA 1. 0 mg·L-1+ NAA 0. 1 mg·L-1+GA35. 0 mg·L-1 and then transferred onto the medium of MS + 6-BA 1. 0 mg/L + 2,4-D 0. 2 mg·L-1 for proliferation. The proliferation coefficient was 4. 2 under these mediums. The plantlets were cultured on a rooting medium of 1/2 MS + NAA 0. 5 mg·L-1,and the rooting rate was 93. 63%. The rooted plantlets were transplanted in the substrate which was composed of pearlite,peat and vermiculite at a ratio of 1∶ 1∶ 1,and their survival rate was up to 80% after they hardened off outdoor for 30 d.
The stem of Cerasus serrulata var. lannesiana ‘Sirotae’with buds were used as explants,sterilized and cultured on mediums with various combinations and concentrations of plant growth regulators for rapid progagation. The explants were cultured in a medium of MS + 6-BA 1. 0 mg·L-1+ NAA 0. 1 mg·L-1 to induce shoots. The shoots were then subcultured in the medium of MS + 6-BA 1. 0 mg·L-1+ NAA 0. 1 mg·L-1+GA35. 0 mg·L-1 and then transferred onto the medium of MS + 6-BA 1. 0 mg/L + 2,4-D 0. 2 mg·L-1 for proliferation. The proliferation coefficient was 4. 2 under these mediums. The plantlets were cultured on a rooting medium of 1/2 MS + NAA 0. 5 mg·L-1,and the rooting rate was 93. 63%. The rooted plantlets were transplanted in the substrate which was composed of pearlite,peat and vermiculite at a ratio of 1∶ 1∶ 1,and their survival rate was up to 80% after they hardened off outdoor for 30 d.
2018, 9(3): 339-343.
doi: 10.15886/j.cnki.rdswxb.2018.03.011
Abstract:
An attempt was made to clarify the combining ability of several late-bolting radish parents with better comprehensive characteristics. A total of 8 parents of late-bolting radish were used for crossing based on a 4 × 4 incomplete diallel cross. Genetic analysis of agronomic characteristics of F1 generation in 16 crosses of radish was carried out on the basis of indexes including combining ability and heritability. The results showed there were highly significant differences in 7 characteristics,i. e. root length,leaf length,length of exposed root,leaf weight,spread angle,plant height and root thickness among different combinations. Three desirable parental materials,23-8,9-8 and 15-7,and 4 crossing combinations with greater root thickness and better comprehensive characteristics,（ 9-8） ×（ 15-7）,（ 18-3） ×（ 7-9）,（ 18-3） ×（ 15-7） and（ 23-8） ×（ 7-9）,were selected.
An attempt was made to clarify the combining ability of several late-bolting radish parents with better comprehensive characteristics. A total of 8 parents of late-bolting radish were used for crossing based on a 4 × 4 incomplete diallel cross. Genetic analysis of agronomic characteristics of F1 generation in 16 crosses of radish was carried out on the basis of indexes including combining ability and heritability. The results showed there were highly significant differences in 7 characteristics,i. e. root length,leaf length,length of exposed root,leaf weight,spread angle,plant height and root thickness among different combinations. Three desirable parental materials,23-8,9-8 and 15-7,and 4 crossing combinations with greater root thickness and better comprehensive characteristics,（ 9-8） ×（ 15-7）,（ 18-3） ×（ 7-9）,（ 18-3） ×（ 15-7） and（ 23-8） ×（ 7-9）,were selected.
2018, 9(3): 344-349.
doi: 10.15886/j.cnki.rdswxb.2018.03.012
Abstract:
Shanlan upland rice variety Baishabainuo was cultivated under wetting irrigation in different mulching patterns with non-mulching as a control,and its growth duration,the soil moisture content,the dry weight of weeds and yield components in all the treatments were determined to analyze the effect of different mulching patterns on the agronomic traits of Shanlan upland rice and weed control. The results showed that the growth duration of Shanlan upland rice was shortened by 5-7 days in the mulching treatments as against the control（ non-mulching）. The soil moisture content during the growth Stage was higher in the mulching treatments than in the control in the order of rice straw ＞ non-woven fabric ＞ non-mulching. Weed control was better in the mulching treatments than in the control in the order of non-woven fabric ＞ rice straw ＞ non-mulching. The non-woven fabric mulching and rice straw mulching had an overall weed control of 59. 62%-94. 75% and 35%-74. 43%,respectively. The actual yield of Shanlan upland rice in the non-woven fabrics mulching pattern was increased by 3. 3% as compared to that of the non-mulching treatment. Upland cultivation with mulching increased rice yield and played a role in water conservation and weed control. The mulching with non-woven fabric was the best in weed control,soil moisture retention and rice yield increase in Shanlan rice cultivation.
Shanlan upland rice variety Baishabainuo was cultivated under wetting irrigation in different mulching patterns with non-mulching as a control,and its growth duration,the soil moisture content,the dry weight of weeds and yield components in all the treatments were determined to analyze the effect of different mulching patterns on the agronomic traits of Shanlan upland rice and weed control. The results showed that the growth duration of Shanlan upland rice was shortened by 5-7 days in the mulching treatments as against the control（ non-mulching）. The soil moisture content during the growth Stage was higher in the mulching treatments than in the control in the order of rice straw ＞ non-woven fabric ＞ non-mulching. Weed control was better in the mulching treatments than in the control in the order of non-woven fabric ＞ rice straw ＞ non-mulching. The non-woven fabric mulching and rice straw mulching had an overall weed control of 59. 62%-94. 75% and 35%-74. 43%,respectively. The actual yield of Shanlan upland rice in the non-woven fabrics mulching pattern was increased by 3. 3% as compared to that of the non-mulching treatment. Upland cultivation with mulching increased rice yield and played a role in water conservation and weed control. The mulching with non-woven fabric was the best in weed control,soil moisture retention and rice yield increase in Shanlan rice cultivation.
2018, 9(3): 350-357.
doi: 10.15886/j.cnki.rdswxb.2018.03.013
Abstract:
A systematic observation was made on the morphology of the flowers and fruits of the germplasm materials of Ilex kudingcha C. J. Tseng conserved in the Kudingcha Germplasm Banks of Hainan University. The results showed that there were some morphological differences of the flower and that of the fruits in I. kudingcha,between the descriptions in typical taxonomic literature and our observations. According to the typical taxonomic literature,the number of floral parts of I. kudingcha is 4,while our observations showed that the number of floral parts was usually 4,but 3,5,6,even 8 foral parts were also observed in some florets. These differences mainly showed as the followings. 1) The number of petals in a floret was usually 4,but 3,5,6,even 8 petals were also observed in the same floret. The number of stamens in a floret was usually 4,but 3,5,6,even 8 stamens were also observed in the same floret. 2) Usually,there were 4 loculi in an ovary. But 2,3,5,6,even8 loculi were also observed in the same ovary in some germplasm materials. 3) Usually,there were 4 pits in a fruit. But 3,5,6,even 8 pits were also observed in a few of fruits in some germplasm materials. 4) According to the descriptions of the typical taxonomic literature there was only 1 ovule in a loculus of ovary. However,2 ovules could also be observed in the same loculus in few. of gerplasm materials. Which was the so-called "polyembryony". The mechanism of polyembryony occurrence,as well as the latent importance in breeding of the perennial woody plant,such as I. kudingcha,were discussed in this paper. 5) According to the descriptions of the typical taxonomic literature,the plants of I. kudingcha were dioecious. While our observation results showed that the plants of I. kudingcha were usually dioecious,that the typical male germplasm materials accounted for 45. 45%,and that the typical fame germplasm materials accounted for 44. 16%. However,there were an other 10. 39 % germplasm materials,in which the undeveloped ovaries of the different flores were degenerate by different degrees. A series of transition types could be observed,from a small protuberance of the undeveloped ovaries to the complete flowers with normally developed stamens and pistils.
A systematic observation was made on the morphology of the flowers and fruits of the germplasm materials of Ilex kudingcha C. J. Tseng conserved in the Kudingcha Germplasm Banks of Hainan University. The results showed that there were some morphological differences of the flower and that of the fruits in I. kudingcha,between the descriptions in typical taxonomic literature and our observations. According to the typical taxonomic literature,the number of floral parts of I. kudingcha is 4,while our observations showed that the number of floral parts was usually 4,but 3,5,6,even 8 foral parts were also observed in some florets. These differences mainly showed as the followings. 1) The number of petals in a floret was usually 4,but 3,5,6,even 8 petals were also observed in the same floret. The number of stamens in a floret was usually 4,but 3,5,6,even 8 stamens were also observed in the same floret. 2) Usually,there were 4 loculi in an ovary. But 2,3,5,6,even8 loculi were also observed in the same ovary in some germplasm materials. 3) Usually,there were 4 pits in a fruit. But 3,5,6,even 8 pits were also observed in a few of fruits in some germplasm materials. 4) According to the descriptions of the typical taxonomic literature there was only 1 ovule in a loculus of ovary. However,2 ovules could also be observed in the same loculus in few. of gerplasm materials. Which was the so-called "polyembryony". The mechanism of polyembryony occurrence,as well as the latent importance in breeding of the perennial woody plant,such as I. kudingcha,were discussed in this paper. 5) According to the descriptions of the typical taxonomic literature,the plants of I. kudingcha were dioecious. While our observation results showed that the plants of I. kudingcha were usually dioecious,that the typical male germplasm materials accounted for 45. 45%,and that the typical fame germplasm materials accounted for 44. 16%. However,there were an other 10. 39 % germplasm materials,in which the undeveloped ovaries of the different flores were degenerate by different degrees. A series of transition types could be observed,from a small protuberance of the undeveloped ovaries to the complete flowers with normally developed stamens and pistils.
2018, 9(3): 358-362.
doi: 10.15886/j.cnki.rdswxb.2018.03.014
Abstract:
A morphological observation of vegetative organs of Plukenetia volubilis L collected from Qicha Town,Changjiang County,Hainan Province was made by using paraffin section technique. The results show that the roots,stems and leaves of P. volubilis are similar to those of dicotyledonous plants. The xylem of the roots was well developed and composed of a lot of vessels. The vessels were different in diameter and distributed in a scattered and irregular way. The pericyclic cells at the periphery of the xylem were transformed into meristem to form a lateral root growth point which continued to form lateral roots. The lateral roots were numerous and well developed. The pith of the stem was obvious,and was composed of parenchyma cells in the young stem. The mature older stem was hollow in the center of the pith with an obvious pith ring,and the vessels in the stems were large and numerous. The leaves were heterofacial; their palisade tissues were small and long,and closely arranged;their spongy parenchyma tissues were loosely arranged with intercellular inclusions of large cells; there were two layers of vascular tissues in the main vein of the leaf,and the vascular tissues in the mature old leaves were huge; in the lower side of the leaf the mechanical tissues were well developed,and the secondary veins were fewer and seldom had vascular bundles.
A morphological observation of vegetative organs of Plukenetia volubilis L collected from Qicha Town,Changjiang County,Hainan Province was made by using paraffin section technique. The results show that the roots,stems and leaves of P. volubilis are similar to those of dicotyledonous plants. The xylem of the roots was well developed and composed of a lot of vessels. The vessels were different in diameter and distributed in a scattered and irregular way. The pericyclic cells at the periphery of the xylem were transformed into meristem to form a lateral root growth point which continued to form lateral roots. The lateral roots were numerous and well developed. The pith of the stem was obvious,and was composed of parenchyma cells in the young stem. The mature older stem was hollow in the center of the pith with an obvious pith ring,and the vessels in the stems were large and numerous. The leaves were heterofacial; their palisade tissues were small and long,and closely arranged;their spongy parenchyma tissues were loosely arranged with intercellular inclusions of large cells; there were two layers of vascular tissues in the main vein of the leaf,and the vascular tissues in the mature old leaves were huge; in the lower side of the leaf the mechanical tissues were well developed,and the secondary veins were fewer and seldom had vascular bundles.
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