【目的】为探究UV-B和重金属Cd双重胁迫对麦长管蚜Sitobion avenae(Fabricius)生长发育和繁殖的影响,以及UV-B和重金属Cd两因素间的交互作用。【方法】在室内,不同辐射强度UV-B(0,0.1,0.2和0.7 m W/cm^2)与不同浓度重金属Cd(0,20,40,80...【目的】为探究UV-B和重金属Cd双重胁迫对麦长管蚜Sitobion avenae(Fabricius)生长发育和繁殖的影响,以及UV-B和重金属Cd两因素间的交互作用。【方法】在室内,不同辐射强度UV-B(0,0.1,0.2和0.7 m W/cm^2)与不同浓度重金属Cd(0,20,40,80和160 mg/kg)处理后,采用特定年龄生命表方法,统计麦长管蚜种群参数、繁殖参数、存活率和繁殖力的变化。【结果】麦长管蚜种群的生命表各参数受UV-B与重金属Cd双重胁迫影响显著,且UV-B对麦长管蚜的生命表各参数影响要大于重金属Cd;UV-B和重金属Cd两因素间存在交互作用。同一重金属Cd浓度时,随着UV-B辐射强度的增加,麦长管蚜种群的内禀增长率r、周限增长率λ、净增殖率R_0、繁殖力F、产仔天数和成虫寿命均呈现先下降后上升的趋势,且均在UV-B辐射强度为0.2 m W/cm^2时下降至最低点;而麦长管蚜种群的平均世代周期T则呈现先升高后下降的趋势,且在UV-B辐射强度为0.1m W/cm^2时上升至最高点。同一UV-B辐射强度下,随着重金属Cd浓度的增加,麦长管蚜种群生命表各参数均呈现波动变化;双重胁迫处理组麦长管蚜种群内禀增长率r、周限增长率λ、净增殖率R_0、繁殖力F、产仔天数和成虫寿命均显著低于单一重金属Cd处理组,而其平均世代周期T显著高于单一重金属Cd处理组,且双重胁迫处理组生命表各参数的峰值点较单一因素重金属Cd处理组均呈现不同程度的提前。【结论】UV-B与重金属Cd影响麦长管蚜种群的生长发育和繁殖,且由于这两因素间存在交互作用,二者双重胁迫对麦长管蚜种群的生长发育和繁殖影响更加严重。展开更多
This study was carried out to detect content of heavy metals( Pb,Cd,and As) in vegetables,understand the current situation of heavy metal contamination in vegetables,and to provide scientific reference for further res...This study was carried out to detect content of heavy metals( Pb,Cd,and As) in vegetables,understand the current situation of heavy metal contamination in vegetables,and to provide scientific reference for further researches. It randomly selected 6 large vegetable markets and 6 supermarkets in Changsha City,selected 8 types of typical vegetables,and detected 96 samples. In accordance with maximum level of contaminants in foods in existing GB2762- 2012 standard,Nemerow composite pollution index( Pt) and grading standards,it made evaluation: uncontaminated( Pt≤ 1),mildly contaminated( 1 < Pt≤2),moderately contaminated( 2 < Pt≤3),and highly contaminated( Pt>3). Among 96 samples,range of content of Pb,Cd and As is( 0. 06- 1. 41),( 0. 06- 1. 26) and( 0. 00- 0. 91) mg / kg respectively; the over- limit rate of these metals exceeding the safety level is 78. 13%,45. 83%,and 34. 38% separately; the composite pollution index is in( 0. 90-6. 05),the eggplant is 6. 05 and hot pepper is 3. 24; the content of Pb( F =23. 908,P =0. 001) and Cd( F =64. 908,P =0. 000)are significantly different between 8 types of vegetables and there is no significant difference between the content of As( F = 4. 634,P = 0. 705> 0. 05) in 8 types of vegetables. Study shows that common vegetables in Changsha City has problem of excess Pb,Cd and As,and the Pb over- limit rate is the highest. The composite pollution index indicates that most heavy metal contamination of vegetables is mild and moderate contamination,melon,fruit and vegetable contamination is high contamination,and Cd is the major factor leading to contamination of melons,fruits and vegetables.展开更多
文摘【目的】为探究UV-B和重金属Cd双重胁迫对麦长管蚜Sitobion avenae(Fabricius)生长发育和繁殖的影响,以及UV-B和重金属Cd两因素间的交互作用。【方法】在室内,不同辐射强度UV-B(0,0.1,0.2和0.7 m W/cm^2)与不同浓度重金属Cd(0,20,40,80和160 mg/kg)处理后,采用特定年龄生命表方法,统计麦长管蚜种群参数、繁殖参数、存活率和繁殖力的变化。【结果】麦长管蚜种群的生命表各参数受UV-B与重金属Cd双重胁迫影响显著,且UV-B对麦长管蚜的生命表各参数影响要大于重金属Cd;UV-B和重金属Cd两因素间存在交互作用。同一重金属Cd浓度时,随着UV-B辐射强度的增加,麦长管蚜种群的内禀增长率r、周限增长率λ、净增殖率R_0、繁殖力F、产仔天数和成虫寿命均呈现先下降后上升的趋势,且均在UV-B辐射强度为0.2 m W/cm^2时下降至最低点;而麦长管蚜种群的平均世代周期T则呈现先升高后下降的趋势,且在UV-B辐射强度为0.1m W/cm^2时上升至最高点。同一UV-B辐射强度下,随着重金属Cd浓度的增加,麦长管蚜种群生命表各参数均呈现波动变化;双重胁迫处理组麦长管蚜种群内禀增长率r、周限增长率λ、净增殖率R_0、繁殖力F、产仔天数和成虫寿命均显著低于单一重金属Cd处理组,而其平均世代周期T显著高于单一重金属Cd处理组,且双重胁迫处理组生命表各参数的峰值点较单一因素重金属Cd处理组均呈现不同程度的提前。【结论】UV-B与重金属Cd影响麦长管蚜种群的生长发育和繁殖,且由于这两因素间存在交互作用,二者双重胁迫对麦长管蚜种群的生长发育和繁殖影响更加严重。
基金Supported by Student Innovation Project of Central South University(YC12355)
文摘This study was carried out to detect content of heavy metals( Pb,Cd,and As) in vegetables,understand the current situation of heavy metal contamination in vegetables,and to provide scientific reference for further researches. It randomly selected 6 large vegetable markets and 6 supermarkets in Changsha City,selected 8 types of typical vegetables,and detected 96 samples. In accordance with maximum level of contaminants in foods in existing GB2762- 2012 standard,Nemerow composite pollution index( Pt) and grading standards,it made evaluation: uncontaminated( Pt≤ 1),mildly contaminated( 1 < Pt≤2),moderately contaminated( 2 < Pt≤3),and highly contaminated( Pt>3). Among 96 samples,range of content of Pb,Cd and As is( 0. 06- 1. 41),( 0. 06- 1. 26) and( 0. 00- 0. 91) mg / kg respectively; the over- limit rate of these metals exceeding the safety level is 78. 13%,45. 83%,and 34. 38% separately; the composite pollution index is in( 0. 90-6. 05),the eggplant is 6. 05 and hot pepper is 3. 24; the content of Pb( F =23. 908,P =0. 001) and Cd( F =64. 908,P =0. 000)are significantly different between 8 types of vegetables and there is no significant difference between the content of As( F = 4. 634,P = 0. 705> 0. 05) in 8 types of vegetables. Study shows that common vegetables in Changsha City has problem of excess Pb,Cd and As,and the Pb over- limit rate is the highest. The composite pollution index indicates that most heavy metal contamination of vegetables is mild and moderate contamination,melon,fruit and vegetable contamination is high contamination,and Cd is the major factor leading to contamination of melons,fruits and vegetables.
