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野生条件下扬子鳄的吼叫规律 被引量:7
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作者 吴建盛 王小明 《Zoological Research》 CAS CSCD 北大核心 2004年第4期281-286,共6页
20 0 3年在安徽扬子鳄自然保护区对扬子鳄的吼叫规律进行了为期一年的专题研究。在监测中 ,记录了吼叫日期、吼叫时间、吼叫数和天气情况。扬子鳄在每年的 3月开始吼叫 ,11月停止吼叫 ;扬子鳄的吼叫数在不同的月份差异极显著 (χ2 检验 ... 20 0 3年在安徽扬子鳄自然保护区对扬子鳄的吼叫规律进行了为期一年的专题研究。在监测中 ,记录了吼叫日期、吼叫时间、吼叫数和天气情况。扬子鳄在每年的 3月开始吼叫 ,11月停止吼叫 ;扬子鳄的吼叫数在不同的月份差异极显著 (χ2 检验 :χ2 =4 4 8 2 9,df=8,P <0 0 1) ,其中 6月扬子鳄吼叫最为频繁 ,其吼叫数占全年的 2 6 0 % ;繁殖期间 (6— 9月 )扬子鳄吼叫数明显高于非繁殖期 (Mann WhitneyU检验 :U =2 0 ,P <0 0 5 ) ;在每天的不同时间扬子鳄的吼叫数呈极显著差异 (χ2 =2 33 18,df =17,P <0 0 1) ,存在明显的吼叫高峰 ,白天吼叫多于晚上 (U =12 5 ,P <0 0 5 ) ;天气的变化对吼叫没有影响。分析表明 ,扬子鳄的吼叫与其繁殖行为关系紧密 ,吼叫的主要目的是为了吸引异性 ,同时有保护领域的功能。 展开更多
关键词 野生条件 安徽扬子鳄自然保护区 扬子鳄 吼叫规律 繁殖行为
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濒危植物九龙山榧与其同属广布种榧树叶绿素荧光特性的比较 被引量:2
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作者 郑英茂 周钰鸿 +3 位作者 潘成椿 刘菊莲 蓝本宽 康华靖 《林业资源管理》 北大核心 2021年第1期86-93,共8页
分别以栽培和野生条件下的九龙山榧(Torreya jiulongshanensis)(雌、雄株)及同属广布种——榧树(T.grandis)为材料,比较了其叶片叶绿素荧光参数对光强的响应,以期为九龙山榧种质资源保育提供科学依据。结果表明,栽培条件下,九龙山榧雌... 分别以栽培和野生条件下的九龙山榧(Torreya jiulongshanensis)(雌、雄株)及同属广布种——榧树(T.grandis)为材料,比较了其叶片叶绿素荧光参数对光强的响应,以期为九龙山榧种质资源保育提供科学依据。结果表明,栽培条件下,九龙山榧雌株幼苗叶片的光系统I最大荧光值整体高于榧树及九龙山榧的雄株;九龙山榧雌、雄株幼苗的光饱和点也较高,分别为788.581和550.640μmol/(m^(2)·s),所对应的最大电子传递速率也较高,分别为40.690和39.546μmol/(m^(2)·s)。同样,在野外条件下,九龙山榧雌、雄株的光饱和点也均显著高于榧树,分别为1165.361和1416.817μmol/(m^(2)·s),光系统II最大电子传递速率也以九龙山榧雌株为最高,其值为80.322μmol/(m^(2)·s)。由此可见,九龙山榧为阳生树种,且与榧树相比具有更强的光合潜力。 展开更多
关键词 九龙山榧 榧树 栽培条件 野生条件 荧光参数 光强
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Saline Stress Response of Plantlets of Common Wheat (Triticum aestivum) and Its Wild Congeners 被引量:1
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作者 N. V. Terletskaya A. B. Rysbekova +2 位作者 A. B. Iskakova N. A. Khailenko F. A. Polimbetova 《Journal of Agricultural Science and Technology(B)》 2011年第2期198-204,共7页
The aim of this work was to study the reactions of wheat (T. aestivum L.) and its wild congeners under salt stress. Physiological mechanisms that underlie traits for salt tolerance plantlets have been used to test s... The aim of this work was to study the reactions of wheat (T. aestivum L.) and its wild congeners under salt stress. Physiological mechanisms that underlie traits for salt tolerance plantlets have been used to test some wheat species and to identify sources of salty tolerance. Stress conditions were founded by means of exposure of the plantlets in NaCI water solution, 1.68% that demonstrably differentiates the samples by growth parameters. Under laboratory conditions the ability of seedlings to bear a significant shortage of water, their ability to accumulate biomass, changing the parameters of linear growth processes and changes in water content in leaves and roots of seedlings under stress was determined. Interest is also the rate of growth of root fibrils in saline conditions. These experiments allowed to provide a comprehensive diagnosis of studied forms of wheat and make an initial opinion on their salt tolerance. Different features of abiotic stress responses of some wheat species at the early stages of development were shown that testifies necessi~ of great number of approaches at selection of genetic material for improvement of modern wheat eultivars. This work is the first phase of research for practical breeding. 展开更多
关键词 Saline stress response PLANTLETS T. aestivum L. wild congeners.
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Vertebral deformities in hatchery-reared and wild-caught juvenile Japanese flounder,Paralichthys olivaceus
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作者 吕红健 张秀梅 +3 位作者 付梅 席丹 苏胜齐 姚维志 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第1期84-91,共8页
The present study compared vertebral deformities of hatchery-reared and wild-caught juvenile Japanese flounder, Paralichthys olivaceus. A total of 362 hatchery-reared flounder (total length 122.5- 155.8 mm) were col... The present study compared vertebral deformities of hatchery-reared and wild-caught juvenile Japanese flounder, Paralichthys olivaceus. A total of 362 hatchery-reared flounder (total length 122.5- 155.8 mm) were collected from three commercial hatcheries located in Yantai, East China, and 89 wild fish (total length 124.7 161.3 mm) were caught offYangma Island near Yantai City (37°27′N, 121°36′E). All the fish were dissected, photographed, and images of the axial skeleton were examined for vertebral deformities. Compared with wild-caught flounder in which no deformed vertebrae were detected, 48 (13.3%) hatchery- reared fish had deformed vertebrae. The deformities were classified as compression, compression-ankylosis, and dislocation-ankylosis. The vertebral deformities were mainly localized between post-cranial vertebra 1 and 3, with vertebrae number 1 as the most commonly deformed. The causative factors leading to vertebral deformities in reared Japanese flounder may be related to unfavorable temperature conditions, inflammation, damage, or rupture to the intervertebral ligaments under rearing conditions. Furthermore, no significant difference in the total number of vertebral bodies was observed between wild-caught (38.8±0.4) and hatchery-reared flounder (38.1±0.9) (P〉0.05). However, the number of vertebral bodies of hatchery-reared and wild-caught flounder ranged from 35 to 39 and from 38 to 39, respectively. 展开更多
关键词 Paralichthys olivaceus hatchery-reared wild-caught DEFORMITIES VERTEBRAE
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Influence of Saline Stress on Ionic Balance of Wheat (Triticum Aestivum) and Its Wild Congeners
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作者 Nina Terletskaya Batyrbek Sarsenbayev Yerlan Kirshibayev 《Journal of Life Sciences》 2011年第8期618-624,共7页
Purpose of this work was to study changes in the ion balance under salt stress in roots and leaves of seedlings of T. aestivum L. and its wild congeners with different genomic composition. Laboratory assessment of sal... Purpose of this work was to study changes in the ion balance under salt stress in roots and leaves of seedlings of T. aestivum L. and its wild congeners with different genomic composition. Laboratory assessment of salt tolerance in seedlings was carried out and contents of ions K^+, Na^+ and Ca^2+ in roots and leaves were defined. Considerable change of ionic balance in roots and leaves of studied forms of wheat against salt stress is shown. It is noticed that the parity K^+/Na^+ decreases in process of strengthening of salt stress. Authentic negative correlation between a relative gain of a biomass of leaves and roots in the stress conditions and accumulation of ions Na^+ and between a relative gain of a biomass of leaves in the stress conditions and a parity in them of ions K^+/Na^+ is revealed. The research results also show that the stability characteristics of indicators of changes in ionic composition or balance in the leaves of young plants are more informative than in the roots and allow to reveal the form, characterized by relatively high of K^+/Na^+ ratio and the relatively low accumulation of Ca2^+ as the most resistant to salt stress. 展开更多
关键词 Saline stress response PLANTLETS ions T. aestivum L. wild congeners.
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Genotype and Environmental Effects on Cadmium Concentration in Maize
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作者 Vlado Kovacevic Antun Vragolovic 《Journal of Life Sciences》 2011年第11期926-932,共7页
Seven parents and their 21 Fl diallel crosses of maize were grown under field conditions in the 2001 and 2002 growing seasons on two soils mutually air-distanced 800 m (BI = fluvisol and B2 = stagnic albeluvisol; pH ... Seven parents and their 21 Fl diallel crosses of maize were grown under field conditions in the 2001 and 2002 growing seasons on two soils mutually air-distanced 800 m (BI = fluvisol and B2 = stagnic albeluvisol; pH in KCI = 7.02 and 3.85, humus = 2.75 and 2.02, CaCO3 = 11.4% and 0, for B 1 and B2, respectively). Also, the B 1 and B2 were differently in NH4Acetate-EDTA soluble fraction (mg.kgl: calcium 25,500 and 2,300; zinc 1.61 and 0.53; cadmium 0.195 and 0.064, respectively). The experiments were conducted in four replicates (the basic plot 16.8 m2) in a randomized complete block design. The ear-leaf was taken at the beginning of silking and grain samples at maturity. Mean leaf-Cd (mg Cd.kg-t in dry matter) were 0.102 and 0.072, for 2001 and 2002; 0.064 and 0.195, for BI and B2, while differences in level of genotype were from 0.040 to 0.581 (the parents) and from 0.046 to 0.171 (the hybrids). Six hybrids of Bc707-1 had considerably higher leaf-Cd in comparison with six hybrids of Bc265-1 (means 0.100 and 0.050 respectively). Grain-Cd was under detectable range (〈 0.040) with exception of Bc707-1 parent on the B2 soil (0.17 mg Cd-kg^-1). 展开更多
关键词 CADMIUM GENOTYPE grain leaf MAIZE soil effects year effects
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Different Growth Characteristics of Grewia mollis, Grewia tenax and Grewia villosa Under Nursery and Field Conditions
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作者 Niemat Abdalla Saleem Khalil Ayoub Adam Mohamed Mohamed El Nour 《Journal of Life Sciences》 2012年第9期1016-1024,共9页
This study was carried out to assess the growth characteristics of Grewia moll&, Grewia tenax and Grewia villosa under the nursery and field conditions. Two experiments were conducted at the farm of the College of Na... This study was carried out to assess the growth characteristics of Grewia moll&, Grewia tenax and Grewia villosa under the nursery and field conditions. Two experiments were conducted at the farm of the College of Natural Resources and Environmental Studies, University of Juba, Khartoum, Sudan. Randomized complete block design with three replications was used. Morphological and physiological factors were measured. Seedlings height, number of leaves, number of branches and sub-branches were different (P 〈 0.05) among the three species at the nursery stage and under field conditions. Collar diameter showed significant difference among the species under field conditions. Physiological factors exhibited more significant variations in the field than at the nursery stage. Variations in growth characteristics were attributed to genetics differences and different growth habit, while variations in physiological factors (photosynthesis and transpiration rate) were attributed to differences in leaf structure, size and number of stomatal pores. 展开更多
关键词 The nursery and field conditions Grewia mollis Grewia tenax Grewia villosa growth characteristics
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