稻粉虱的发生及其化学防治药剂筛选     

魏琪  何佳春  赖凤香  王渭霞  万品俊  傅强 《植物保护》2023,49(4):284-292

稻粉虱Aleurocybotus indicus David et Subramaniam, 属半翅目粉虱科, 以刺吸式口器为害水稻叶片而导致产量损失, 是我国闽?赣?浙等稻区的一种偶发性水稻害虫, 近20多年已鲜有报道, 但2019年-2021年在中国水稻研究所富阳试验农场稻田暴发?本文描述了稻粉虱的为害症状和形态特征, 并配以原色照片; 克隆得到了稻粉虱线粒体DNA COⅠ基因片段, 发现其与烟粉虱Bemisia tabaci序列一致性最高(85.80%); 田间调查表明, 富阳试验农场及周边稻田稻粉虱均有不同程度的发生, 但前者发生量明显较高(每个分蘖最高可达251头), 推测可能与农场温室内的稻粉虱越冬虫源有关; 利用稻苗浸渍法评估了不同作用机制的7种杀虫剂对稻粉虱的毒力, 发现双丙环虫酯?氯虫苯甲酰胺?氟啶虫胺腈?氟啶虫酰胺和溴氰虫酰胺对稻粉虱成虫均有较好的杀虫活性, 其中前4种药剂推荐中剂量处理后72 h的校正死亡率均可达100%, 其LC50分别为3.028?3.769?6.405 mg/L和7.894 mg/L?本研究可为我国稻粉虱的识别诊断和化学防治提供重要依据?  相似文献   

Case- carburization Numerical Modeling and Craft Optimization on Steel Parts of Various Shapes     

LAI Hong  LIU Tian mo 《保鲜与加工》2002,(12):46-48

According to the diffusion equation of carburizing process and its boundary conditionand initial condition, various shapes steel parts are modeled under various case carburize craft parameters, concentration distribution curves have been obtained. Various craft parameters are compared, and carburizing temperature has more influence on carbon concentration distribution. Various shapes steel parts' carbon concentration distribution curves have some difference. According to the carbon concentration distribution curve, craft parameters can be adjusted in order to obtain the best carburizing craft.  相似文献   

p300/p53/Smad3 pathway involved in aging-related atrial fibrosis in human atrial fibroblasts     

LAI Ying-yu  GAO Xiao-yan  ZHOU Hui-shan  LI Xin  WANG Zhao-yu  PENG De-wei  RAO Fang  DENG Chun-yu 《园艺学报》2021,37(1):18-26

AIM To investigate the role of p300 in aging-related atrial fibrosis in human atrial fibroblasts （HAFs） and its potential mechanism. METHODS HAFs were obtained from human left atrial tissue, and the senescence model was established by cell passage. Senescence-associated β-galactosidase （SA-β-Gal） staining was used to detect the cell senescence, and Western blot was used to determine the protein levels of p300, p53, Smad3 and other senescence and fibrosis associated proteins in HAFs. RESULTS Compared to passage 3 HAFs, the proportion of senescent cells, and the protein levels of p300, p53, p-Smad3 and other senescence and fibrosis associated proteins were increased in HAFs at passage 7 and 11 （P<0.05）. After treated with curcumin （a p300 inhibitor） or transfection with p300 small-hairpin （sh） RNA plasmid, the protein levels of p300, and the senescence and fibrosis associated proteins were decreased in HAFs at passage 7（P<0.05）. Up-regulation of p300 by transfection with p300 over-expression plasmid increased the protein levels of p53, Smad3 and MMP-2 in HAFs at passage 3 （P<0.05）. CONCLUSION p300/p53/Smad3 signaling pathway plays an important role in aging-related atrial fibrosis in HAFs.  相似文献   

环境伦理学对中国风景园林发展的启示     

赖国传  张文英 《广东园林》2007,29(1):22-25

论述了环境伦理学指导我国园林发展的必要性,以及环境伦理学对我国园林发展的启示,从而对环境伦理学在园林事业发展中的应用进行探讨,提出在城市发展决策和风景园林规划设计,以及在相关法律、法规和行政机构、社会结构中确立环境伦理学价值观的重要意义。  相似文献   

园林植物新树种-银叶金合欢   总被引：1，自引：0，他引：1  

代色平  朱纯  赖晋灵  黄永芳  董斌  叶振华 《广东园林》2007,29(4):40-42

银叶金合欢是独具一格、观赏价值极高的植物。该文阐述其形态特征、生态习性、种子特性、播种繁殖技术、生长特性和物候等植物基本特性,并提出养护管理要点,简单评述其观赏特性和园林用途。  相似文献   

基于RapidSCAN CS-45的新疆滴灌冬小麦氮肥推荐研究     

赖宁  耿庆龙  李青军  赵海燕  陈署晃 《麦类作物学报》2021,41(1):96-104

为给滴灌小麦氮营养状况实时评估和氮肥合理施用提供参考,通过2年田间定位试验,以当地主栽品种新冬22号为试验材料,设置5个施氮水平(0、120、240、360、480 kg· hm-2),利用主动式光谱仪RapidScan CS-45获取各生育时期冠层归一化植被指数(NDVI)和归一化红边植被指数(NDRE),分析其与滴...  相似文献   

河南省苹果园鞘翅目天敌昆虫资源发生种类记述——步甲科Carabdae   总被引：3，自引：3，他引：0  

高九思  赵增渠  来学仁 《河南农业科学》2007,(9):61-63

详细描述了鞘翅目步甲科3属6种,等天敌昆虫的分类地位、形态特征,简述了天敌昆虫的生活习性、发生程度。  相似文献   

Impacts of wetting-drying cycles on short-term carbon and nitrogen dynamics in Amynthas earthworm casts     

Michelle Man Suet LAW  Derrick Yuk Fo LAI 《土壤圈》2021,31(3):423-432

Effects of earthworm casts on soil nutrient dynamics and their responses to changing moisture availability in subtropical ecosystems remain poorly understood. This study aimed to examine short-term carbon(C) and nitrogen(N) dynamics and their interactions with wetting-drying cycles in three different structural forms(i.e., granular, globular, and heap-like) of Amynthas earthworm casts. The rates of C and N mineralization in the earthworm casts were examined under two different wetting-drying cycles(i.e., 2-d and 4-d wetting intervals) using a rainfall simulation experiment. After three simulated rainfall events, subsamples of the earthworm casts were further incubated for 4 d for the determination of CO_2 and N_2O fluxes. The results of this study indicated that the impacts of wetting-drying cycles on the short-term C and N dynamics were highly variable among the three cast forms, but wetting-drying cycles significantly reduced the cumulative CO_2 and N_2O fluxes by 62%–83% and 57%–85%, respectively, when compared to the control without being subjected to any rainfall events. The C mineralization rates in different cast forms were affected by the amount of organic substrates and N content in casts, which were associated with the food preference and selection of earthworms. Meanwhile, the cumulative N_2O fluxes did not differ among the three cast forms. Repeated wetting and drying of casts not only enhanced aggregate stability by promoting bonds between the cast particles, but also inhibited microbial survival and growth during the prolonged drying period, which together hindered decomposition and denitrification. Our findings demonstrated that the interactions between the structural forms, aggregate dynamics, and C and N cycling in the earthworm casts were highly complex.  相似文献   

沼液施用对土壤与植物中磷分布的影响     

范韵  来柳青  朱立群  徐一帆  宋照亮 《土壤通报》2012,(3):702-705

以余杭青菜地潮土、红壤为例,选取未施加沼液、正常施加沼液以及加倍施加的土壤剖面各3条,研究沼液施加对土壤和植物磷(P)分布的影响,为畜禽废弃物资源化利用和瓜果合理施肥提供科学依据。结果表明:(1)沼液施加能够提高表层土壤的总P含量,而对深层土壤的总P含量影响不大;(2)沼液施加后,土壤中的Fe-P含量会有显著增加;(3)青菜茎和叶中的总P含量随沼液施加量的增加而增加,其中叶增加的趋势最明显。  相似文献   

放牧与围栏内蒙古针茅草原土壤微生物生物量碳、氮变化及微生物群落结构PLFA分析     

赵帅  张静妮  赖欣  杨殿林  赵建宁  李刚  邹雨坤 《农业环境保护》2011,(6):1126-1134

以内蒙古贝加尔针茅草原、大针茅草原和克氏针茅草原为研究对象,采用氯仿熏蒸法和磷脂脂肪酸（PLFA）分析方法研究了放牧与围栏条件下内蒙古针茅草原土壤微生物生物量和群落结构特征的变化情况。研究表明放牧与围栏草地土壤微生物生物量和群落结构差异显著。氯仿熏蒸法分析结果表明内蒙古针茅草原土壤微生物生物量碳的含量介于166.6-703.5mg·kg^-1之间,微生物生物量氮含量介于30.34-92.15mg·kg^-1之间,其中贝加尔针茅草原土壤微生物生物量碳、氮最高,大针茅草原次之,克氏针茅草原则最低。放牧条件下,贝加尔针茅草原、大针茅草原土壤微生物生物量碳、氮显著低于围栏草地,克氏针茅草原则无显著变化。PLFA分析结果显示,内蒙古针茅草原土壤微生物群落PLFAs种类、含量丰富,共检测出28种PLFA生物标记磷脂脂肪酸,并且以直链饱和脂肪酸和支链饱和脂肪酸为主,相对含量占总量的2/3左右,其中贝加尔针茅草原土壤微生物含量最丰富,其围栏样地土壤的PLFA含量达到27.3nmol·g-1,大针茅草原和克氏针茅草原依次降低。围栏条件下,各类型草原土壤细菌脂肪酸与总PLFA含量均显著高于放牧草地,真菌脂肪酸含量则因草原类型不同各有差异;放牧导致各类型草原革兰氏阳性细菌PLFAs/革兰氏阴性细菌PLFAs（GPPLFAs/GNPLFAs）比值显著降低,而除了克氏针茅草原,细菌PLFAs/真菌PLFAs比值则显著升高。PLFAs主成分分析表明,放牧和围栏处理对内蒙古针茅草原土壤微生物群落结构产生影响,且围栏处理的影响程度大于放牧处理。经相关分析表明,氯仿熏蒸法和PLFA分析方法之间有很好的一致性,且土壤微生物PLFAs与土壤有机质、全磷、硝态氮显著相关。  相似文献