17个邓恩桉种源引种试验初报   总被引：2，自引：0，他引：2  

谢红梅  柏劲松 《桉树科技》2011,(2):21-26

通过对17个邓恩桉种源在引种后其前7 a生长量和适应性进行调查和分析,结果表明：7年生材积最大的17923号达到了172.4442 m3.hm-2;其次是17915和17918号,均超过了160 m3.hm-2;最小的20670号也达到了119.9361 m3.hm-2。各种源的生长虽然各有差异,但总的来说,高、径增长情况基本一致,所有的种源号均在第3年增长得最快;17个种源均能适应永州市的气候,能抵抗当地的低温冰冻和高温干旱天气,抗病虫害能力强。  相似文献   

枯草芽孢杆菌 DJ-6与吡唑醚菌酯及其混配对草莓枯萎病的室内抑菌活性与田间促生防病效果     

吉沐祥  姚克兵  李国平  吴祥  陈宏洲  庄义庆 《农业科学与技术》2014,(11):2020-2025

[目的]筛选草莓枯萎病增效生物复配杀菌剂。[方法]采用菌丝生长速率法测定枯草芽孢杆菌 DJ-6与吡唑醚菌酯及其5种配比对草莓枯萎病菌的室内抑菌活性,采用田间试验测定20%吡唑醚菌酯·200亿 cfu/g枯草芽孢杆菌可湿性粉剂1000倍液、2000倍液、3000倍液以及各单剂对草莓生长性状的影响和对草莓枯萎病菌的防治效果。[结果]枯草芽孢杆菌DJ-6与吡唑醚菌酯及1∶1、1∶2、1∶3、1∶4、1∶5混配组合对草莓枯萎病菌的 EC50分别为5.3115、4.0086、3.5706、3.3509、3.2189μg/ml;5种混配组合对枯萎病菌的增效系数（SR）分别为2.28、1.77、1.53、1.64、1.11,其中以1∶1增效作用最大。20%吡唑醚菌酯·200亿cfu/g枯草芽孢杆菌可湿性粉剂三种不同浓度混配及各单剂均有促进草莓生长和防治枯萎病的效果,其中高、中浓度处理高于低浓度和单剂处理。药后30 d和80 d测定枯萎病防治效果,高浓度的防效最高为100.00%和93.11%;中浓度的防效为92.49%和86.49%,高于低浓度和各单剂处理;低浓度的防效分别为82.61%和72.42%,高于1000亿cfu/g枯草芽孢杆菌可湿性粉剂1000倍液,但低于250 g/L吡唑醚菌酯乳油2000倍液。[结论]20%吡唑醚菌酯·200亿 cfu/g枯草芽孢杆菌可湿性粉剂定植后的灌根浓度推荐为1000~2000倍液。  相似文献   

菜用紫云英品种筛选及高效施肥模式研究     

何春梅  兰忠明  林新坚  刘珠  钟少杰  李文霞  李昱 《福建省农科院学报》2014,(4):334-338

通过大田比较试验,筛选出营养价值丰富、口感佳、产量高的菜用紫云英品种“闽紫7号”、“8487711”、“84341022”和“浙紫5-12”,并以“闽紫7号”为研究对象,明确了基肥施用钙镁磷肥375 kg · hm -2,苗期追施1次尿素30 kg ·hm -2和氯化钾45 kg · hm-2是菜用紫云英最佳施肥模式,以期为菜用型紫云英高效种植提供技术支撑。  相似文献   

基于SPOT5的县级土地利用现状调查技术研究     

张娅香  李秉柏  何静 《广东农业科学》2007,(11):47-51

以浙江省台州市三门县为例,运用SPOT5不同空间分辨率的融合影像进行土地利用类型调查及面积遥感调查,通过对数据进行选择与预处理工作,利用ERDAS IMAGINE 8.4图像处理软件,对遥感影像进行配准、几何精纠正、融合等,在对研究区土地利用类型的分类中,采用人机交互判读方式,并提出一套适宜高分辨率遥感影像土地利用分类的技术路线.  相似文献   

玻璃苗中纤维素、木素及元素含量变化的研究   总被引：7，自引：0，他引：7  

李云  田砚亭  罗晓芳 《核农学报》1997,11(2):0-0

本研究通过＾１４Ｃ－葡萄糖参与珠美海棠玻璃化发生过程中的代谢活动，测定了玻璃苗不同部位的纤维素和木素中的放射性活度，摸清了玻璃苗中纤维素和木素含量的分布状况及变化。利用中子活化分析技术测定了玻璃苗不同部位中的多种元素含量和分布状况及变化。结果表明，玻璃苗中纤维素和木素的合成速度比正常苗降低了１０．３８％，降解速度增加了１８．７６％，造成玻璃苗中纤维素和木素含量下降４３．６８％，玻璃苗不同部位中绝大  相似文献   

Is the endangered Fennoscandian arctic fox (Alopex lagopus) population genetically isolated?     

Love DalénAnders Götherström  Magnus TannerfeldtAnders Angerbjörn 《Biological conservation》2002,105(2):171-178

The arctic fox population in Fennoscandia is on the verge of going extinct after not being able to recover from a severe bottleneck at the end of the 19th century. The Siberian arctic fox population, on the other hand, is large and unthreatened. In order to resolve questions regarding gene flow between, and genetic variation within the populations, a 294 bp long part of the mitochondrial hypervariable region 1 was sequenced. This was done for 17 Swedish, 15 Siberian and two farmed foxes. Twelve variable nucleotide sites were observed, which resulted in 10 different haplotypes. Three haplotypes were found in Sweden and seven haplotypes were found in Siberia. An analysis of molecular variance showed a weak, but significant, differentiation between the populations. No difference in haplotype diversity was found between the populations. A phylogenetic analysis revealed that the three Swedish haplotypes were not monophyletic compared to the Siberian haplotypes. These results indicate a certain amount of gene flow between the two populations, both before and after the bottleneck. Restocking the Fennoscandian population with arctic foxes from Siberia might therefore be a viable option.  相似文献   

白狐源星状病毒RdRp基因的鉴定及遗传演化分析     

冀锦朝  黄勉  卢刚  欧嘉俊  彭仕明  萨家祺  李守军 《华南农业大学学报》2021,42(1):12-16

目的 探究广州动物园一例死亡白狐Alopex lagopus肾脏中鉴定出的星状病毒的遗传变异情况。方法 对死亡白狐进行剖检,利用半巢式RT-PCR对内脏器官进行病原学检测,对扩增出的病毒株的RdRp基因序列进行相似性分析。结果 死亡白狐的肾脏苍白肿大,被膜难以剥离,肾脏中检测出的星状病毒RdRp基因呈阳性。RdRp基因与9株参考毒株的核苷酸相似性为67.5%～96.2%,其中与香港猫源星状病毒1637F的核苷酸相似性(96.2%)最高。结论 本研究为星状病毒在野生哺乳动物间的跨种传播及肠外器官中的感染提供了依据。  相似文献   

中草药对热应激鸡十二指肠黏膜结构的影响（英文）     

高桂生  陈娟  刘欢  邢超  史秋梅  沈萍  高光平  张艳英 《农业科学与技术》2015,(1):103-106,146

伊莎褐88日龄雏鸡120只,随机分为6组,3个对照组(常温组、高温组、高温Vc组)和3个中草药高温组(高剂量组、中剂量组、低剂量组)。常温组在14~25℃环境下饲养,其余5组在28~39℃环境下饲养.试验全程共10天,在试验的第1、4、8、10天每组各剖杀5只并取其十二指肠。经常规方法制成组织切片后H.E染色,测定各十二指肠的黏膜厚度、绒毛长度、隐窝深度。结果显示:热应激状态下,十二指肠黏膜厚度和绒毛长度均显著低于常温组,且绒毛稀疏。但是高温条件下,中草药高剂量组、中剂量组各项指标均高于高温组和高温Vc组,特别是在试验的第8天和第10天差异极显著,并且中草药高剂量组各指标显著高于中草药中低剂量组。该处方对热应激鸡十二指肠粘膜的保护作用强于高温Vc组。在热应激条件下中草药有效减弱了十二指肠粘膜的组织损伤。  相似文献   

Toxicity and binding analyses of Bacillus thuringiensis toxin Vip3A in Cry1Ac-resistant and-susceptible strains of Helicoverpa armigera (Hübner)     

ZHANG Qian  CHEN Li-zhen  LU Qiong  ZHANG Yan  LIANG Ge-mei 《中国农业科学(英文版)》2015,(2):347-354

The Bacillus thuringiensis vegetative insecticidal protein, Vip3 A, represents a new family of Bt toxin and is currently applied to commercial transgenic cotton. To determine whether the Cry1Ac-resistant Helicoverpa armigera is cross-resistant to Vip3 Aa protein, insecticidal activities, proteolytic activations and binding properties of Vip3 Aa toxin were investigated using Cry1Ac-susceptible(96S) and Cry1Ac-resistant H. armigera strain(Cry1Ac-R). The toxicity of Vip3 Aa in Cry1Ac-R slightly reduced compared with 96 S, the resistance ratio was only 1.7-fold. The digestion rate of full-length Vip3 Aa by gut juice extracts from 96 S was little faster than that from Cry1Ac-R. Surface plasmon resonance(SPR) showed there was no significant difference between the binding affinity of Vip3 Aa and BBMVs between 96 S and Cry1Ac-R strains, and there was no significant competitive binding between Vip3 Aa and Cry1 Ac in susceptible or resistant strains. So there had little cross-resistance between Vip3 Aa and Cry1 Ac,Vip3A+Cry proteins maybe the suitable pyramid strategy to control H. armigera in China in the future.  相似文献   

Antimicrobial ability and growth promoting effects of feed supplemented with probiotic bacterium isolated from gut microlfora of Cirrhinus mrigala     

Anita Bhatnagar  Ritu Lamba 《中国农业科学(英文版)》2015,(3)

The present studies were conducted to isolate, select, identify and characterize gut bacteria as antimicrobial and growth promoting agent for the feed of economical y important ifsh Cirrhinus mrigala. ...  相似文献