Study On Allelopathy Of Several Chinese Herbon Heterosigma Akashiwoand Its Ecological Safety

Based on the allelopathy and using algieidal test and ecological safety analysis of different Chinese herb.Studied the inhibition effect and mechanism on H.akashiwo,The aim was to find to the Chinese herb of safe and effective.The main results of this study were as follow:1.Study on selection and combination of algae inhibition and its effect.According to the allelopathy relationship,several materials with strong algal inhibition have been screened out from nine species of Chinese herbs(0.1%)according to the inhibitory rates(IR),the inhibitory time,the effective inhibitory concentrations and so on.Screened out can quickly and effectively inhibit H.akashiwo has Rhizomaeoptidis,Cortexphellodendri,Cortexphellodendri(high temperature,HT),Allium cepa(Normal atmospheric temperature,NAT)and Mustard(NAT).and can effectively inhibit H.akashiwo has Radixscutellariae,Green tea,Allium cepa(HT)and Cortexphellodendri(NAT),followed by Betel nut and Plum?The results showed that the combined use was not significantly more effective than single herb.In addition,the effective inhibition of algae for at least 7 days.By comparing the different extraction methods and different concentrations of algae inhibition effect.It was found that the inhibitory effect of different extraction methods on Radixscutellariae,Plum,Betel nut,Green tea,Allium cepa,mustard and Cortexphellodendri were significantly different in the first 2d.By comparing the inhibitory effects of different concentrations of Chinese herb,it was found that the concentration of Green tea,Rhizomaeoptidis and mustard was 0.08%,the concentration of Radixscutellariae was as high as 0.02%,and the concentration of Allium cepa was more than 0.2%.2.The mechanisms of Algal inhibiting herbt were also clarified.The results showed that both Rhizoma coptidis and mustard at the concentrations tested could decrease the relative contents of key components in algae such as Protein and chlorophyll,.With the increase of the concentrations of Rhizoma coptidis and mustard,the activity of algal catalase increased also.By contrary,the activities of superoxide dismutase were mostly lower than the control with a fluctuation.In general,Rhizoma coptidis and mustard could significantly decrease the photosynthetic rate and increase the respiratory rate.It can be inferred that Rhizomacoptidis and mustard can inhibit algal mobility and even bring to death by changing the components of cells and making the algal metabolism abnormal.3.Application safety evaluation of algae inhibition plants.The ecological safety of the these Chinese herbs obtained in the growth tests of four familiar and three harmful species of algae,the toxicity test for two species of zooplanktos and one specie of fish.By analyzing the median lethal concentration(24h,48h)and the safety concentration,to evaluate the ecological safety of different Chinese herbs.And the study of five Chinese herbs as feed attractant on the zebrafish to provide the reference.The results showed that the growth Chlorella sp.and Chlorella ellipsoidea were not affected by Rhizoma coptidis(0.05%,0.1%)in the 3 days.And showed that the growth Chlorella sp.,Chlorella ellipsoidea and Platymonas were not affected by mustard(0.05%,0.1%)in the 3 days.The effect of harmful algae was greater than that of the familiar algae,and with the increase of concentration,the inhibition rate increased obviously.The toxicity of Chinese herb on the Moinan mongolica can be ranked from weak to strong as the population of Scutellaria baicalensis Georgi,Rhizoma coptidis,mustard.The toxicity of Chinese herb on the Daphniamagna Straus can be ranked from weak to strong as the population of Allium cepa,Scutellaria baicalensis Georgi,green tea.The toxicity of Chinese herb on thezebrafish can be ranked from weak to strong as the population of Allium cepa,Rhizoma coptidis,Scutellaria baicalensis Georgi,green tea,mustard.And the toxicity of zooplankton and fish increased with the increase of concentration.The attract effect of Chinese herb on thezebrafish can be ranked from strong to weak as the population of Scutellaria baicalensis Georgi,Rhizoma coptidis,green tea,Allium cepa,but mustard did not?The ratio of efficiency to safety(RES),an integrative issue used first time in the paper considering the inhibitory effect and toxicology,can help for the choice of cheap safe Chinese herb.On the whole,Allium cepa,Rhizoma coptidis,Scutellaria baicalensis Georgi,mustard were good algicides with low risk for the aquatic.