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1.
[Objective] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp.[Method] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system.[Result] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius,then their number would increase with growth. During whole rearing period,both heterobacteria in larvae,vibrios in water would increase by one order of magnitude,while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude.There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait.The correlation coefficients between larvae and heterobacteria and vibrios in water were 0.704 and 0.840 in culture system respectively,while the correlation among heterobacteria,vibrios in living bait and larvae,water were weak or negative.[Conclusion] There was a dynamic relation between water and larvae in rearing period,and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus,besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system.  相似文献   

2.
[Objective] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp.[Method] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system.[Result] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius,then their number would increase with growth. During whole rearing period,both heterobacteria in larvae,vibrios in water would increase by one order of magnitude,while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude.There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait.The correlation coefficients between larvae and heterobacteria and vibrios in water were 0.704 and 0.840 in culture system respectively,while the correlation among heterobacteria,vibrios in living bait and larvae,water were weak or negative.[Conclusion] There was a dynamic relation between water and larvae in rearing period,and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus,besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system.  相似文献   

3.
《农业科学与技术》2016,(3):694-699
Ustilaginoidea virens is the causal agent of a serious disease of rice. To reveal the relationship between germination and the 3'-5'-cyclic adenosine monophosphate (cAMP) content from the dormant (black or green-black) and non-dormant(yel ow) chlamydospore in Ustiloginoidea virens,this study adopts ultrasonic-bath method and high-performance liquid chromatography (HPLC) method, for extraction cAMP content of the different color chlamydospore. The results demonstrated that, as for the freshly chlamydospores col ected from the false smut bal s during their germination, cAMP content of yel ow chlamydospore ap-peared a slight growth during 0-12 h, and showed a rapid declining as the germination time extended (12-48 h) . Above al , in yel ow chlamydospores, the germination rate and the content of cAMP presented a very notably negative correlation (|r|=0.861 9>r0.01=0.834), but the correlation between germination rate and content of cAMP was not obvious in black chlamydospores. The germination rate and the content of cAMP presented a notably positive correlation under different storage period (0, 2, 4, 6, 8, 10 months) of the two color chlamydospores (the yel ow of chlamydospore: |r| = 0.785 1 > r0.05 = 0.707; the black of chlamy-dospore: |r| = 0.957 9 > r0.05 = 0.707).  相似文献   

4.
饲草玉米扦插繁殖技术研究(英文)   总被引:18,自引:1,他引:17  
[Objective] The experiment aimed to provide technical guidance for cutting propagation of forage maize SAUMZI.[Method]The survival situation of cuttings at different stem parts and with different internodes numbers and nutrient basis of cutting growth were studied in this experiment.[Result]The survival of young cutting was high while the rooting rate,germination rate and soluble sugar content of lower part of old stem and young cutting were all high.The rooting rate and survival rate with two nodes were higher than those with one node.The total nitrogen content in young stem and in all stems of two-year-old strain were relatively high while soluble sugar content was positively correlated to germination rate,however,total nitrogen content did not show obvious correlation with rooting rate and germination rate.[Conclusion]The young cutting possessed the highest survival rate and germination rate.  相似文献   

5.
[Objective] The aim of this study was to investigate the characteristics and mechanism of chemical emasculation in rapeseed and to provide the theoretical basis for development and utilization of new chemical gametocides.[Method] The activity of peroxidase,catalase and the content of hydrogen peroxide,malondialdehyde in leaves and flower buds of Brassica napus cultivars Qinyou No.3 and L89 induced by the chemical gametocide EXP in the course of male sterility were studied.[Result] Protective enzyme activity and the content of hydrogen peroxide,malondialdehyde in rapeseed treated with EXP changed significantly,which indicated that active oxygen metabolism was abnormal.Furthermore,there was a significant difference in the reaction degree of different cultivars and organs treated by EXP.[Conclusion] There was a correlation between the disturbance of active oxygen metabolism and the male sterility induced by chemical gametocide EXP.  相似文献   

6.
[Objective] The aim of this study was to investigate the characteristics and mechanism of chemical emasculation in rapeseed and to provide the theoretical basis for development and utilization of new chemical gametocides.[Method] The activity of peroxidase,catalase and the content of hydrogen peroxide,malondialdehyde in leaves and flower buds of Brassica napus cultivars Qinyou No.3 and L89 induced by the chemical gametocide EXP in the course of male sterility were studied.[Result] Protective enzyme activity and the content of hydrogen peroxide,malondialdehyde in rapeseed treated with EXP changed significantly,which indicated that active oxygen metabolism was abnormal.Furthermore,there was a significant difference in the reaction degree of different cultivars and organs treated by EXP.[Conclusion] There was a correlation between the disturbance of active oxygen metabolism and the male sterility induced by chemical gametocide EXP.  相似文献   

7.
[Objective] The aim of this study was to investigate the characteristics and mechanism of chemical emasculation in rapeseed and to provide the theoretical basis for development and utilization of new chemical gametocides.[Method] The activity of peroxidase,catalase and the content of hydrogen peroxide,malondialdehyde in leaves and flower buds of Brassica napus cultivars Qinyou No.3 and L89 induced by the chemical gametocide EXP in the course of male sterility were studied.[Result] Protective enzyme activity and the content of hydrogen peroxide,malondialdehyde in rapeseed treated with EXP changed significantly,which indicated that active oxygen metabolism was abnormal.Furthermore,there was a significant difference in the reaction degree of different cultivars and organs treated by EXP.[Conclusion] There was a correlation between the disturbance of active oxygen metabolism and the male sterility induced by chemical gametocide EXP.  相似文献   

8.
[Objective] This study was to reveal the differences in crude fat and glucosinolates between self pollinated seeds and naturally pollinated seeds in Brassica napus in sichuan ecological region. [Method] Near-infrared spectroscopy method (NIRS) was employed to measure the quality components in self pollinated seeds and naturally pollinated seeds of 861 shares of Brassica napus from Sichuan ecological region. And correlation analysis and regression analysis were conducted based on the experimental data via SPSS (statistics package for social science). [Result] The contents of crude fat in the self pollinated seeds were commonly a higher than that in the naturally pollinated seeds at 0.01 significant level; while the contents of glucosinolates in the self pollinated seeds and the naturally pollinated seeds were insignificantly different. Both the correlation relationship and linear regression for the crude fat between the self pollinated seeds and naturally pollinated seeds reached the significant level. The regression equations for the contents of crude fat(y1) and glucosinolates(y2) in the naturally pollinated seeds and of crude fat(x1) and glucosinolates(x2) in self pollinated seeds were respectively determined to be y1=16.844+0.614x1 and y2=-0.620+1.017x2. [Conclusion] In Brassica napus breeding, crude fat in naturally pollinated seeds should be emphatically taken into account, meanwhile concurrently considering that in self pollinated seeds; while glucosinolates in both the self pollinated seeds and the naturally pollinated seeds must be simultaneously concerned.  相似文献   

9.
The total phenolic and flavonoid contents in the fruit tissues(peels,pulp residues,seeds,and juices)of 19 citrus genotypes belonged to Citrus reticulata Blanco were evaluated and their antioxidant capacity was tested by 2,2-diphenyl-1-picrylhydrazyl radicals(DPPH)method and 2,2′-azino-bis(3-ethylbenzthiozoline-6)-sulphonic acid(ABTS)method.The total phenolic and flavonoid contents,and their antioxidant capacity varied in different citrus fruit tissues.Generally,the peel had both the highest average of total phenolics(27.18 mg gallic acid equivalent(GAE)g~(–1 )DW)and total flavonoids(38.97 mg rutin equivalent(RE)g~(–1) DW).The highest antioxidant capacity was also the average of DPPH value(21.92 mg vitamin C equivalent antioxidant capacity(VCEAC)g~(–1 )DW)and average of ABTS value(78.70 mg VCEAC g~(–1) DW)in peel.The correlation coefficient between the total phenolics and their antioxidant capacity of different citrus fruits tissues ranged from 0.079 to0.792,and from–0.150 to 0.664 for the total flavonoids.The antioxidant capacity of fruit tissues were correlated with the total phenoilc content and flavonoid content except in case of the peel.In addition,the total phenolic content and antioxidant capacity varied in different citrus genotypes.Manju and Karamandarin were better genotypes with higher antioxidation and the phenolic content,however Shagan was the poorest genotype with lower antioxidation and the phenolic content.  相似文献   

10.
[Objective] The ratio of flesh content and biochemical compositions in muscles of Pachyhynobius shangchengensis were researched in this experiment to provide basic referrences for studying nutritive physiological ecology of Pachyhynobius shangchengensis.[Method]The biochemical analytic method was used to detect the ratio of flesh content and biochemical compositions in muscle of Pachyhynobius shangchengensis.[Result]The ratio of flesh contents of female and male Pachyhynobius shangchengensis were 54.93% and 55.84% respectively.The contents of protein,total saccharides and fatty acid of female Pachyhynobius shangchengensis were 15.44%,1.70% and 0.68% respectively,while the same contents of male Pachyhynobius shangchengensis were 15.67%,1.89% and 0.53% respectively.The total content of 18 kinds of amino acids was 12.72%(the proportion in fresh weight),among which the content of 8 kinds of essential amino acids was 4.68%.The essential amino acids index(EAAI)was 72.68 and limiting amino acids was valine.There were 11 kinds of fatty acids in muscles of Pachyhynobius shangchengensis,among which the content of unsaturated fatty acids(80.02%)was higher than that of saturated fatty acids(19.98%).[Conclusion] Pachyhynobius shangchengensis was a kind of valuable natural resource belonging to the nutritious type of low fat content and high protein content.  相似文献   

11.
本文论述了IPV6产生的社会原因,阐述了国外发达国家下一代Internet的发展状况和中国下一代Internet的发展状况及最新进展。  相似文献   

12.
13.
孙淑芬 《北京农业》2011,(3):208-209
吉林省通榆县向海水库为通榆县水利事业发展做出了突出贡献。分析向海水库发展的现状,认为要加强对向海水库的管理,因地制宜,通过向海这一品牌发展旅游经济。  相似文献   

14.
树冠圆满度对树木生长的影响及作用研究   总被引:4,自引:0,他引:4  
树冠是树木的重要组成部分,其数量指标———树冠圆满度不仅客观地反映了树木占有生长空间的状况及竞争能力,而且对树木的生长过程和树木的形状都有着非常重要的影响。研究结果表明:在树木直径、树高较小(或年龄小)时,其树干材积也较小,而树冠圆满度较大,随着直径、树高的增加,其树干材积随之增加,但树冠圆满度逐渐变小。所以,树冠圆满度与直径、树高及树干材积之间存在着紧密的相关关系,其相关指数(R)基本上在0 80以上,而形数与树冠圆满度之间呈正相关。  相似文献   

15.
猪场空气细菌数量与猪高热综合征的相关性研究   总被引:5,自引:0,他引:5  
自2001年入夏以来,浙江、上海等许多地区的猪群中流行以持续高热、气喘、皮肤发红为主要特征的猪"高热综合征",给养猪业带来了巨大的损失.但到目前为止,其主要病原依然未被确定.为了研究空气中细菌含量与该病的发生和严重程度之间的关系,我们对浙江省几个不同规模、不同发病情况的猪场的空气细菌含量进行了测试.结果发现:该病的发生及严重程度与猪舍内空气的细菌含量存在着明显的正相关性.  相似文献   

16.
从犯的原因力是指成立从犯所必需的因行为人的行为与其他人的犯罪行为之间产生的内在的必然联系。从犯是否成立,要经过一般性判断、具体性判断和排除性判断三个环节。一般性判断主要考虑是否具有成立从犯所要求的主观要件和客观要件,具体性判断涉及事前判断与事后判断、主观判断和客观判断、应然判断与实然判断,排除性判断主要考虑刑法分则的特殊规定和刑法总则中的但书。  相似文献   

17.
将信息理论与物流模型的研究挂接 ,定义了生态系统的信息熵和信息流量。以各分室输出量占总体的份额作为系统选择该分室的概率。通过对系统聚合度和冗余度的分析 ,推导了二者对各分室的灵敏度。对黑龙江省双城市双城镇永和村的物流模型进行了灵敏度分析。计算结果表明 ,籽粒和土壤分室对系统的稳定性起重要作用 ;而调整畜牧业的结构 ,改变农肥的投入量等 ,可以有效地改善系统的物流情况 ,使系统向良性循环  相似文献   

18.
刺五加种胚生长发育规律的分析   总被引:1,自引:0,他引:1  
为解决刺五加种子休眠难以打破,一般情况下种子出苗率很低的难题,对当年生刺五加种胚的生长发育规律进行了研究.结果表明,种胚生长发育表现出S形生长曲线,即前期缓慢生长期,中期快速生长期,及再次缓慢生长的生理后熟期.各个时期所需要的适宜温度和时间各不相同,在种子处理的各个阶段及时调整好适宜温度时,裂口率可达70%以上,裂口籽发芽率可达90%以上.  相似文献   

19.
屯垦戍边环境变化分析   总被引:1,自引:0,他引:1  
兵团成立50多年以来,特别是改革开放以来,兵团屯垦戍边的环境已经发生了很大的变化,本文对屯垦戍边的政治、经济、文化、军事环境的变化进行分析,在此基础上提出兵团屯垦戍边的目标、内容、管理体制和形式要与这种环境的变化相适应,以促进兵团屯垦戍边事业在新的环境下更上一层楼,更好履行屯垦戍边的使命。  相似文献   

20.
从经济学角度而言,完备的合同必须具备四方面条件:完全竞争的市场;完全的理性;无外部负效应;零交易成本。但这些条件均不具有现实性。合同法的功能就是纠正合同的非完备性,使之趋于完备。在此分析基础上,对我国《合同法》的立法目的进行了审视。  相似文献   

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