for Journals by Title or ISSN
for Articles by Keywords
help

Publisher: Oxford University Press   (Total: 392 journals)

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

        1 2 | Last   [Sort by number of followers]   [Restore default list]

Showing 1 - 200 of 392 Journals sorted alphabetically
Acta Biochimica et Biophysica Sinica     Hybrid Journal   (Followers: 5, SJR: 0.881, h-index: 38)
Adaptation     Hybrid Journal   (Followers: 8, SJR: 0.111, h-index: 4)
Advances in Nutrition     Hybrid Journal   (Followers: 42, SJR: 2.075, h-index: 36)
Aesthetic Surgery J.     Hybrid Journal   (Followers: 6, SJR: 1.538, h-index: 35)
African Affairs     Hybrid Journal   (Followers: 64, SJR: 1.512, h-index: 46)
Age and Ageing     Hybrid Journal   (Followers: 86, SJR: 1.611, h-index: 107)
Alcohol and Alcoholism     Hybrid Journal   (Followers: 18, SJR: 0.935, h-index: 80)
American Entomologist     Full-text available via subscription   (Followers: 6)
American Historical Review     Hybrid Journal   (Followers: 150, SJR: 0.652, h-index: 43)
American J. of Agricultural Economics     Hybrid Journal   (Followers: 40, SJR: 1.441, h-index: 77)
American J. of Clinical Nutrition     Hybrid Journal   (Followers: 147, SJR: 3.771, h-index: 262)
American J. of Epidemiology     Hybrid Journal   (Followers: 173, SJR: 3.047, h-index: 201)
American J. of Hypertension     Hybrid Journal   (Followers: 25, SJR: 1.397, h-index: 111)
American J. of Jurisprudence     Hybrid Journal   (Followers: 18)
American J. of Legal History     Full-text available via subscription   (Followers: 9, SJR: 0.151, h-index: 7)
American Law and Economics Review     Hybrid Journal   (Followers: 27, SJR: 0.824, h-index: 23)
American Literary History     Hybrid Journal   (Followers: 15, SJR: 0.185, h-index: 22)
Analysis     Hybrid Journal   (Followers: 21)
Animal Frontiers     Hybrid Journal  
Annals of Behavioral Medicine     Hybrid Journal   (Followers: 14, SJR: 2.112, h-index: 98)
Annals of Botany     Hybrid Journal   (Followers: 35, SJR: 1.912, h-index: 124)
Annals of Oncology     Hybrid Journal   (Followers: 47, SJR: 4.362, h-index: 173)
Annals of the Entomological Society of America     Full-text available via subscription   (Followers: 8, SJR: 0.642, h-index: 53)
Annals of Work Exposures and Health     Hybrid Journal   (Followers: 29, SJR: 0.837, h-index: 57)
AoB Plants     Open Access   (Followers: 4, SJR: 0.78, h-index: 10)
Applied Economic Perspectives and Policy     Hybrid Journal   (Followers: 16, SJR: 0.884, h-index: 31)
Applied Linguistics     Hybrid Journal   (Followers: 55, SJR: 1.749, h-index: 63)
Applied Mathematics Research eXpress     Hybrid Journal   (Followers: 1, SJR: 0.779, h-index: 11)
Arbitration Intl.     Full-text available via subscription   (Followers: 20)
Arbitration Law Reports and Review     Hybrid Journal   (Followers: 14)
Archives of Clinical Neuropsychology     Hybrid Journal   (Followers: 30, SJR: 0.96, h-index: 71)
Aristotelian Society Supplementary Volume     Hybrid Journal   (Followers: 3, SJR: 0.102, h-index: 20)
Arthropod Management Tests     Hybrid Journal   (Followers: 2)
Astronomy & Geophysics     Hybrid Journal   (Followers: 42, SJR: 0.144, h-index: 15)
Behavioral Ecology     Hybrid Journal   (Followers: 51, SJR: 1.698, h-index: 92)
Bioinformatics     Hybrid Journal   (Followers: 292, SJR: 4.643, h-index: 271)
Biology Methods and Protocols     Hybrid Journal  
Biology of Reproduction     Full-text available via subscription   (Followers: 10, SJR: 1.646, h-index: 149)
Biometrika     Hybrid Journal   (Followers: 20, SJR: 2.801, h-index: 90)
BioScience     Hybrid Journal   (Followers: 30, SJR: 2.374, h-index: 154)
Bioscience Horizons : The National Undergraduate Research J.     Open Access   (Followers: 1, SJR: 0.213, h-index: 9)
Biostatistics     Hybrid Journal   (Followers: 17, SJR: 1.955, h-index: 55)
BJA : British J. of Anaesthesia     Hybrid Journal   (Followers: 165, SJR: 2.314, h-index: 133)
BJA Education     Hybrid Journal   (Followers: 64, SJR: 0.272, h-index: 20)
Brain     Hybrid Journal   (Followers: 68, SJR: 6.097, h-index: 264)
Briefings in Bioinformatics     Hybrid Journal   (Followers: 45, SJR: 4.086, h-index: 73)
Briefings in Functional Genomics     Hybrid Journal   (Followers: 3, SJR: 1.771, h-index: 50)
British J. for the Philosophy of Science     Hybrid Journal   (Followers: 33, SJR: 1.267, h-index: 38)
British J. of Aesthetics     Hybrid Journal   (Followers: 26, SJR: 0.217, h-index: 18)
British J. of Criminology     Hybrid Journal   (Followers: 583, SJR: 1.373, h-index: 62)
British J. of Social Work     Hybrid Journal   (Followers: 86, SJR: 0.771, h-index: 53)
British Medical Bulletin     Hybrid Journal   (Followers: 7, SJR: 1.391, h-index: 84)
British Yearbook of Intl. Law     Hybrid Journal   (Followers: 31)
Bulletin of the London Mathematical Society     Hybrid Journal   (Followers: 4, SJR: 1.474, h-index: 31)
Cambridge J. of Economics     Hybrid Journal   (Followers: 61, SJR: 0.957, h-index: 59)
Cambridge J. of Regions, Economy and Society     Hybrid Journal   (Followers: 10, SJR: 1.067, h-index: 22)
Cambridge Quarterly     Hybrid Journal   (Followers: 9, SJR: 0.1, h-index: 7)
Capital Markets Law J.     Hybrid Journal   (Followers: 2)
Carcinogenesis     Hybrid Journal   (Followers: 2, SJR: 2.439, h-index: 167)
Cardiovascular Research     Hybrid Journal   (Followers: 13, SJR: 2.897, h-index: 175)
Cerebral Cortex     Hybrid Journal   (Followers: 45, SJR: 4.827, h-index: 192)
CESifo Economic Studies     Hybrid Journal   (Followers: 17, SJR: 0.501, h-index: 19)
Chemical Senses     Hybrid Journal   (Followers: 1, SJR: 1.436, h-index: 76)
Children and Schools     Hybrid Journal   (Followers: 5, SJR: 0.211, h-index: 18)
Chinese J. of Comparative Law     Hybrid Journal   (Followers: 4)
Chinese J. of Intl. Law     Hybrid Journal   (Followers: 22, SJR: 0.737, h-index: 11)
Chinese J. of Intl. Politics     Hybrid Journal   (Followers: 8, SJR: 1.238, h-index: 15)
Christian Bioethics: Non-Ecumenical Studies in Medical Morality     Hybrid Journal   (Followers: 10, SJR: 0.191, h-index: 8)
Classical Receptions J.     Hybrid Journal   (Followers: 25, SJR: 0.1, h-index: 3)
Clean Energy     Open Access  
Clinical Infectious Diseases     Hybrid Journal   (Followers: 62, SJR: 4.742, h-index: 261)
Clinical Kidney J.     Open Access   (Followers: 3, SJR: 0.338, h-index: 19)
Communication Theory     Hybrid Journal   (Followers: 20, SJR: 2.62, h-index: 53)
Communication, Culture & Critique     Hybrid Journal   (Followers: 25)
Community Development J.     Hybrid Journal   (Followers: 27, SJR: 0.47, h-index: 28)
Computer J.     Hybrid Journal   (Followers: 9, SJR: 0.371, h-index: 47)
Conservation Physiology     Open Access   (Followers: 2)
Contemporary Women's Writing     Hybrid Journal   (Followers: 9, SJR: 0.111, h-index: 3)
Contributions to Political Economy     Hybrid Journal   (Followers: 5, SJR: 0.313, h-index: 10)
Critical Values     Full-text available via subscription  
Current Developments in Nutrition     Open Access  
Current Legal Problems     Hybrid Journal   (Followers: 27)
Current Zoology     Full-text available via subscription   (Followers: 1, SJR: 0.999, h-index: 20)
Database : The J. of Biological Databases and Curation     Open Access   (Followers: 8, SJR: 1.068, h-index: 24)
Digital Scholarship in the Humanities     Hybrid Journal   (Followers: 14)
Diplomatic History     Hybrid Journal   (Followers: 20, SJR: 0.296, h-index: 22)
DNA Research     Open Access   (Followers: 5, SJR: 2.42, h-index: 77)
Dynamics and Statistics of the Climate System     Open Access   (Followers: 3)
Early Music     Hybrid Journal   (Followers: 15, SJR: 0.124, h-index: 11)
Economic Policy     Hybrid Journal   (Followers: 39, SJR: 2.052, h-index: 52)
ELT J.     Hybrid Journal   (Followers: 25, SJR: 1.26, h-index: 23)
English Historical Review     Hybrid Journal   (Followers: 51, SJR: 0.311, h-index: 10)
English: J. of the English Association     Hybrid Journal   (Followers: 14, SJR: 0.144, h-index: 3)
Environmental Entomology     Full-text available via subscription   (Followers: 11, SJR: 0.791, h-index: 66)
Environmental Epigenetics     Open Access   (Followers: 3)
Environmental History     Hybrid Journal   (Followers: 26, SJR: 0.197, h-index: 25)
EP-Europace     Hybrid Journal   (Followers: 2, SJR: 2.201, h-index: 71)
Epidemiologic Reviews     Hybrid Journal   (Followers: 9, SJR: 3.917, h-index: 81)
ESHRE Monographs     Hybrid Journal  
Essays in Criticism     Hybrid Journal   (Followers: 16, SJR: 0.1, h-index: 6)
European Heart J.     Hybrid Journal   (Followers: 54, SJR: 6.997, h-index: 227)
European Heart J. - Cardiovascular Imaging     Hybrid Journal   (Followers: 8, SJR: 2.044, h-index: 58)
European Heart J. - Cardiovascular Pharmacotherapy     Full-text available via subscription   (Followers: 1)
European Heart J. - Quality of Care and Clinical Outcomes     Hybrid Journal  
European Heart J. Supplements     Hybrid Journal   (Followers: 7, SJR: 0.152, h-index: 31)
European J. of Cardio-Thoracic Surgery     Hybrid Journal   (Followers: 9, SJR: 1.568, h-index: 104)
European J. of Intl. Law     Hybrid Journal   (Followers: 173, SJR: 0.722, h-index: 38)
European J. of Orthodontics     Hybrid Journal   (Followers: 4, SJR: 1.09, h-index: 60)
European J. of Public Health     Hybrid Journal   (Followers: 20, SJR: 1.284, h-index: 64)
European Review of Agricultural Economics     Hybrid Journal   (Followers: 10, SJR: 1.549, h-index: 42)
European Review of Economic History     Hybrid Journal   (Followers: 28, SJR: 0.628, h-index: 24)
European Sociological Review     Hybrid Journal   (Followers: 40, SJR: 2.061, h-index: 53)
Evolution, Medicine, and Public Health     Open Access   (Followers: 10)
Family Practice     Hybrid Journal   (Followers: 14, SJR: 1.048, h-index: 77)
Fems Microbiology Ecology     Hybrid Journal   (Followers: 10, SJR: 1.687, h-index: 115)
Fems Microbiology Letters     Hybrid Journal   (Followers: 22, SJR: 1.126, h-index: 118)
Fems Microbiology Reviews     Hybrid Journal   (Followers: 27, SJR: 7.587, h-index: 150)
Fems Yeast Research     Hybrid Journal   (Followers: 14, SJR: 1.213, h-index: 66)
Food Quality and Safety     Open Access  
Foreign Policy Analysis     Hybrid Journal   (Followers: 23, SJR: 0.859, h-index: 10)
Forest Science     Hybrid Journal   (Followers: 4, SJR: 0.872, h-index: 59)
Forestry: An Intl. J. of Forest Research     Hybrid Journal   (Followers: 16, SJR: 0.903, h-index: 44)
Forum for Modern Language Studies     Hybrid Journal   (Followers: 6, SJR: 0.108, h-index: 6)
French History     Hybrid Journal   (Followers: 32, SJR: 0.123, h-index: 10)
French Studies     Hybrid Journal   (Followers: 20, SJR: 0.119, h-index: 7)
French Studies Bulletin     Hybrid Journal   (Followers: 10, SJR: 0.102, h-index: 3)
Gastroenterology Report     Open Access   (Followers: 2)
Genome Biology and Evolution     Open Access   (Followers: 12, SJR: 3.22, h-index: 39)
Geophysical J. Intl.     Hybrid Journal   (Followers: 35, SJR: 1.839, h-index: 119)
German History     Hybrid Journal   (Followers: 22, SJR: 0.437, h-index: 13)
GigaScience     Open Access   (Followers: 3)
Global Summitry     Hybrid Journal   (Followers: 1)
Glycobiology     Hybrid Journal   (Followers: 14, SJR: 1.692, h-index: 101)
Health and Social Work     Hybrid Journal   (Followers: 55, SJR: 0.505, h-index: 40)
Health Education Research     Hybrid Journal   (Followers: 13, SJR: 0.814, h-index: 80)
Health Policy and Planning     Hybrid Journal   (Followers: 24, SJR: 1.628, h-index: 66)
Health Promotion Intl.     Hybrid Journal   (Followers: 21, SJR: 0.664, h-index: 60)
History Workshop J.     Hybrid Journal   (Followers: 29, SJR: 0.313, h-index: 20)
Holocaust and Genocide Studies     Hybrid Journal   (Followers: 26, SJR: 0.115, h-index: 13)
Human Communication Research     Hybrid Journal   (Followers: 13, SJR: 2.199, h-index: 61)
Human Molecular Genetics     Hybrid Journal   (Followers: 8, SJR: 4.288, h-index: 233)
Human Reproduction     Hybrid Journal   (Followers: 72, SJR: 2.271, h-index: 179)
Human Reproduction Update     Hybrid Journal   (Followers: 17, SJR: 4.678, h-index: 128)
Human Rights Law Review     Hybrid Journal   (Followers: 60, SJR: 0.7, h-index: 21)
ICES J. of Marine Science: J. du Conseil     Hybrid Journal   (Followers: 51, SJR: 1.233, h-index: 88)
ICSID Review     Hybrid Journal   (Followers: 12)
ILAR J.     Hybrid Journal   (Followers: 2, SJR: 1.099, h-index: 51)
IMA J. of Applied Mathematics     Hybrid Journal   (SJR: 0.329, h-index: 26)
IMA J. of Management Mathematics     Hybrid Journal   (SJR: 0.351, h-index: 20)
IMA J. of Mathematical Control and Information     Hybrid Journal   (Followers: 2, SJR: 0.661, h-index: 28)
IMA J. of Numerical Analysis - advance access     Hybrid Journal   (SJR: 2.032, h-index: 44)
Industrial and Corporate Change     Hybrid Journal   (Followers: 10, SJR: 1.37, h-index: 81)
Industrial Law J.     Hybrid Journal   (Followers: 34, SJR: 0.184, h-index: 15)
Inflammatory Bowel Diseases     Hybrid Journal   (Followers: 42, SJR: 1.994, h-index: 107)
Information and Inference     Free  
Integrative and Comparative Biology     Hybrid Journal   (Followers: 7, SJR: 1.911, h-index: 90)
Interacting with Computers     Hybrid Journal   (Followers: 10, SJR: 0.529, h-index: 59)
Interactive CardioVascular and Thoracic Surgery     Hybrid Journal   (Followers: 6, SJR: 0.743, h-index: 35)
Intl. Affairs     Hybrid Journal   (Followers: 56, SJR: 1.264, h-index: 53)
Intl. Data Privacy Law     Hybrid Journal   (Followers: 31)
Intl. Health     Hybrid Journal   (Followers: 5, SJR: 0.835, h-index: 15)
Intl. Immunology     Hybrid Journal   (Followers: 3, SJR: 1.613, h-index: 111)
Intl. J. for Quality in Health Care     Hybrid Journal   (Followers: 34, SJR: 1.593, h-index: 69)
Intl. J. of Constitutional Law     Hybrid Journal   (Followers: 64, SJR: 0.613, h-index: 19)
Intl. J. of Epidemiology     Hybrid Journal   (Followers: 196, SJR: 4.381, h-index: 145)
Intl. J. of Law and Information Technology     Hybrid Journal   (Followers: 5, SJR: 0.247, h-index: 8)
Intl. J. of Law, Policy and the Family     Hybrid Journal   (Followers: 30, SJR: 0.307, h-index: 15)
Intl. J. of Lexicography     Hybrid Journal   (Followers: 10, SJR: 0.404, h-index: 18)
Intl. J. of Low-Carbon Technologies     Open Access   (Followers: 1, SJR: 0.457, h-index: 12)
Intl. J. of Neuropsychopharmacology     Open Access   (Followers: 3, SJR: 1.69, h-index: 79)
Intl. J. of Public Opinion Research     Hybrid Journal   (Followers: 9, SJR: 0.906, h-index: 33)
Intl. J. of Refugee Law     Hybrid Journal   (Followers: 35, SJR: 0.231, h-index: 21)
Intl. J. of Transitional Justice     Hybrid Journal   (Followers: 12, SJR: 0.833, h-index: 12)
Intl. Mathematics Research Notices     Hybrid Journal   (Followers: 1, SJR: 2.052, h-index: 42)
Intl. Political Sociology     Hybrid Journal   (Followers: 36, SJR: 1.339, h-index: 19)
Intl. Relations of the Asia-Pacific     Hybrid Journal   (Followers: 22, SJR: 0.539, h-index: 17)
Intl. Studies Perspectives     Hybrid Journal   (Followers: 9, SJR: 0.998, h-index: 28)
Intl. Studies Quarterly     Hybrid Journal   (Followers: 44, SJR: 2.184, h-index: 68)
Intl. Studies Review     Hybrid Journal   (Followers: 20, SJR: 0.783, h-index: 38)
ISLE: Interdisciplinary Studies in Literature and Environment     Hybrid Journal   (Followers: 1, SJR: 0.155, h-index: 4)
ITNOW     Hybrid Journal   (Followers: 1, SJR: 0.102, h-index: 4)
J. of African Economies     Hybrid Journal   (Followers: 14, SJR: 0.647, h-index: 30)
J. of American History     Hybrid Journal   (Followers: 45, SJR: 0.286, h-index: 34)
J. of Analytical Toxicology     Hybrid Journal   (Followers: 14, SJR: 1.038, h-index: 60)
J. of Antimicrobial Chemotherapy     Hybrid Journal   (Followers: 14, SJR: 2.157, h-index: 149)
J. of Antitrust Enforcement     Hybrid Journal   (Followers: 1)
J. of Applied Poultry Research     Hybrid Journal   (Followers: 4, SJR: 0.563, h-index: 43)
J. of Biochemistry     Hybrid Journal   (Followers: 41, SJR: 1.341, h-index: 96)
J. of Burn Care & Research     Hybrid Journal   (Followers: 9, SJR: 0.713, h-index: 57)
J. of Chromatographic Science     Hybrid Journal   (Followers: 18, SJR: 0.448, h-index: 42)
J. of Church and State     Hybrid Journal   (Followers: 11, SJR: 0.167, h-index: 11)
J. of Communication     Hybrid Journal   (Followers: 50, SJR: 3.327, h-index: 82)
J. of Competition Law and Economics     Hybrid Journal   (Followers: 35, SJR: 0.442, h-index: 16)
J. of Complex Networks     Hybrid Journal   (Followers: 2, SJR: 1.165, h-index: 5)
J. of Computer-Mediated Communication     Open Access   (Followers: 26, SJR: 2.878, h-index: 80)
J. of Conflict and Security Law     Hybrid Journal   (Followers: 13, SJR: 0.196, h-index: 15)
J. of Consumer Research     Full-text available via subscription   (Followers: 41, SJR: 4.896, h-index: 121)
J. of Crohn's and Colitis     Hybrid Journal   (Followers: 9, SJR: 1.543, h-index: 37)
J. of Cybersecurity     Hybrid Journal   (Followers: 3)
J. of Deaf Studies and Deaf Education     Hybrid Journal   (Followers: 8, SJR: 0.69, h-index: 36)

        1 2 | Last   [Sort by number of followers]   [Restore default list]

Journal Cover Annals of Botany
  [SJR: 1.912]   [H-I: 124]   [35 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0305-7364 - ISSN (Online) 1095-8290
   Published by Oxford University Press Homepage  [392 journals]
  • ContentSnapshots
    • Abstract: Four papers in this issue highlight pollination success: Song et al. (pp 641–650), Mochizuki and Kawakita (pp. 651–663), Chapurlat et al. (pp. 711–721), and Albert et al. (pp. 733–740).
      PubDate: Wed, 14 Mar 2018 00:00:00 GMT
       
  • Plant Cuttings
    • Authors: Chaffey N.
      PubDate: Wed, 14 Mar 2018 00:00:00 GMT
       
  • Sucrose supply from leaves is required for aerenchymatous phellem
           formation in hypocotyl of soybean under waterlogged conditions
    • Authors: Takahashi H; Xiaohua Q, Shimamura S, et al.
      Abstract: Background and AimsSoil waterlogging often causes oxygen deficiency in the root systems of plants and severely inhibits plant growth. Formation of aerenchyma – interconnected spaces that facilitate the movement of gases between and within the aerial and submerged parts of plants – is an adaptive trait for coping with waterlogged conditions. Soybean (Glycine max) forms porous secondary tissues known as aerenchymatous phellem (AP), which are derived from the outermost cell layer of phellogen. To understand what factors other than waterlogging are involved in phellogen and AP formation, we examined how their formation in soybean seedlings was affected by darkness, CO2 deficiency and blockage of phloem transport.MethodsAerenchymatous phellem and phellogen formation were expressed as area ratios in cross-sections of hypocotyl. CO2 was depleted by use of calcium oxide and sodium hydroxide. Phloem transport was blocked by heat-girdling of hypocotyls. Sucrose levels were measured by spectrophotometry.Key ResultsUnder light conditions, waterlogging induced the accumulation of high concentrations of sucrose in hypocotyls, followed by phellogen and AP formation in hypocotyls. Phellogen formation and AP formation were inhibited by darkness, CO2 deficiency and blockage of phloem transport. Phellogen formation and AP formation were also inhibited by excision of shoots above the epicotyl, but they recovered following application of sucrose (but not glucose or fructose application) to the cut surface.ConclusionsThe results demonstrate that sucrose derived from leaves is essential for AP and phellogen formation in soybean hypocotyls under waterlogged soil conditions. Maintenance of a high sucrose concentration is thus essential for the development of phellogen and AP and the differentiation of phellogen to AP.
      PubDate: Tue, 23 Jan 2018 00:00:00 GMT
       
  • Diel pattern of floral scent emission matches the relative importance of
           diurnal and nocturnal pollinators in populations of Gymnadenia conopsea
    • Authors: Chapurlat E; Anderson J, Ågren J, et al.
      Abstract: Background and AimsFloral scent is considered an integral component of pollination syndromes, and its composition and timing of emission are thus expected to match the main pollinator type and time of activity. While floral scent differences among plant species with different pollination systems can be striking, studies on intraspecific variation are sparse, which limits our understanding of the role of pollinators in driving scent divergence.MethodsHere, we used dynamic headspace sampling to quantify floral scent emission and composition during the day and at night in the natural habitat of six Scandinavian populations of the fragrant orchid Gymnadenia conopsea. We tested whether diel scent emission and composition match pollinator type by comparing four populations in southern Sweden, where nocturnal pollinators are more important for plant reproductive success than are diurnal pollinators, with two populations in central Norway, where the opposite is true. To determine to what extent scent patterns quantified in the field reflected plasticity, we also measured scent emission in a common growth chamber environment.Key ResultsBoth scent composition and emission rates differed markedly between day and night, but only the latter varied significantly among populations. The increase in scent emission rate at night was considerably stronger in the Swedish populations compared with the Norwegian populations. These patterns persisted when plants were transferred to a common environment, suggesting a genetic underpinning of the scent variation.ConclusionsThe results are consistent with a scenario where spatial variation in relative importance of nocturnal and diurnal pollinators has resulted in selection for different scent emission rhythms. Our study highlights the importance of adding a characterization of diel variation of scent emission rates to comparative studies of floral scent, which so far have often focused on scent composition only.
      PubDate: Thu, 18 Jan 2018 00:00:00 GMT
       
  • Effect of aperture number on pollen germination, survival and reproductive
           success in Arabidopsis thaliana
    • Authors: Albert B; Ressayre A, Dillmann C, et al.
      Abstract: Background and AimsPollen grains of flowering plants display a fascinating diversity of forms, including diverse patterns of apertures, the specialized areas on the pollen surface that commonly serve as the sites of pollen tube initiation and, therefore, might play a key role in reproduction. Although many aperture patterns exist in angiosperms, pollen with three apertures (triaperturate) constitutes the predominant pollen type found in eudicot species. The aim of this study was to explore whether having three apertures provides selective advantages over other aperture patterns in terms of pollen survival, germination and reproductive success, which could potentially explain the prevalence of triaperturate pollen among eudicots.MethodsThe in vivo pollen germination, pollen tube growth, longevity and competitive ability to sire seeds were compared among pollen grains of Arabidopsis thaliana with different aperture numbers. For this, an arabidopsis pollen aperture series was used, which included the triaperturate wild type, as well as mutants without an aperture (inaperturate) and with more than three apertures.Key ResultsAperture number appears to influence pollen grain performance. In most germination and longevity experiments, the triaperturate and inaperturate pollen grains performed better than pollen with higher aperture numbers. In mixed pollinations, in which triaperturate and inaperturate pollen were forced to compete with each other, the triaperturate pollen outperformed the inaperturate pollen.ConclusionsTriaperturate pollen grains might provide the best trade-off among various pollen performance traits, thus explaining the prevalence of this morphological trait in the eudicot clade.
      PubDate: Thu, 18 Jan 2018 00:00:00 GMT
       
  • Waterlogging tolerance, tissue nitrogen and oxygen transport in the forage
           legume Melilotus siculus: a comparison of nodulated and nitrate-fed plants
           
    • Authors: Konnerup D; Toro G, Pedersen O, et al.
      Abstract: Background and AimsSoil waterlogging adversely impacts most plants. Melilotus siculus is a waterlogging-tolerant annual forage legume, but data were lacking for the effects of root-zone hypoxia on nodulated plants reliant on N2 fixation. The aim was to compare the waterlogging tolerance and physiology of M. siculus reliant on N2 fixation or with access to NO3−.MethodsA factorial experiment imposed treatments of water level (drained or waterlogged), rhizobia (nil or inoculated) and mineral N supply (nil or 11 mm NO3−) for 21 d on plants in pots of vermiculite in a glasshouse. Nodulation, shoot and root growth and tissue N were determined. Porosity (gas volume per unit tissue volume) and respiration rates of root tissues and nodules, and O2 microelectrode profiling across nodules, were measured in a second experiment.Key ResultsPlants inoculated with the appropriate rhizobia, Ensifer (syn. Sinorhizobium) medicae, formed nodules. Nodulated plants grew as well as plants fed NO3−, both in drained and waterlogged conditions. The growth and total N content of nodulated plants (without any NO3− supplied) indicated N2 fixation. Respiration rates (mass basis) were highest in nodules and root tips and lowest in basal root tissues. Secondary aerenchyma (phellem) formed along basal root parts and a thin layer of this porous tissue also covered nodules, which together enhanced gas-phase diffusion of O2 to the nodules; O2 was below detection within the infected zone of the nodule interior.ConclusionsMelilotus siculus reliant on N2 fixation grew well both in drained and waterlogged conditions, and had similar tissue N concentrations. In waterlogged conditions the relatively high respiration rates of nodules must rely on O2 movement via the aerenchymatous phellem in hypocotyl, roots and the outer tissue layers of nodules.
      PubDate: Wed, 17 Jan 2018 00:00:00 GMT
       
  • Could seasonally deteriorating environments favour the evolution of
           autogamous selfing and a drought escape physiology through indirect
           selection' A test of the time limitation hypothesis using artificial
           selection in Clarkia
    • Authors: Emms S; Hove A, Dudley L, et al.
      Abstract: Background and AimsThe evolution of selfing from outcrossing may be the most common transition in plant reproductive systems and is associated with a variety of ecological circumstances and life history strategies. The most widely discussed explanation for these associations is the reproductive assurance hypothesis – the proposition that selfing is favoured because it increases female fitness when outcross pollen receipt is limited. Here an alternative explanation, the time limitation hypothesis, is addressed, one scenario of which proposes that selfing may evolve as a correlated response to selection for a faster life cycle in seasonally deteriorating environments.MethodsArtificial selection for faster maturation (early flowering) or for low herkogamy was performed on Clarkia unguiculata (Onagraceae), a largely outcrossing species whose closest relative, C. exilis, has evolved higher levels of autogamous selfing. Direct responses to selection and correlated evolutionary changes in these traits were measured under greenhouse conditions. Direct responses to selection on early flowering and correlated evolutionary changes in the node of the first flower, herkogamy, dichogamy, gas exchange rates and water use efficiency (WUE) were measured under field conditions.Key ResultsLines selected for early flowering and for low herkogamy showed consistent, statistically significant responses to direct selection. However, there was little or no evidence of correlated evolutionary changes in flowering date, floral traits, gas exchange rates or WUE.ConclusionsThese results suggest that the maturation rate and mating system have evolved independently in Clarkia and that the time limitation hypothesis does not explain the repeated evolution of selfing in this genus, at least through its indirect selection scenario. They also suggest that the life history and physiological components of drought escape are not genetically correlated in Clarkia, and that differences in gas exchange physiology between C. unguiculata and C. exilis have evolved independently of differences in mating system and life history.
      PubDate: Wed, 17 Jan 2018 00:00:00 GMT
       
  • Reversible colour change in leaves enhances pollinator attraction and
           reproductive success in Saururus chinensis (Saururaceae)
    • Authors: Song B; Stöcklin J, Armbruster W, et al.
      Abstract: Background and AimsAlthough there has been much experimental work on leaf colour change associated with selection generated by abiotic environmental factors and antagonists, the role of leaf colour change in pollinator attraction has been largely ignored. We tested whether whitening of the apical leaves subtending the inflorescences of Saururus chinensis during flowering enhances pollinator attraction, and whether re-greening of the white leaves after flowering increases carbon assimilation and promotes seed development.MethodsWhite leaves were removed or covered, and the effects of these manipulations on pollinator visitation and subsequent reproductive success were assessed. The net photosynthetic rates of leaves of different colour were measured and their photosynthetic contributions to seed development were evaluated.Key ResultsSaururus chinensis is able to self-pollinate autonomously, but depends largely on flies for pollination. White leaves had different reflectance spectra from green leaves, and white leaves attracted significantly more pollinators and led to significantly higher fruit and seed set. Although leaf whitening resulted in a reduction in photosynthetic capacity, it translated into only a small decrease in seed mass. When leaves had turned back from white to green after flowering their photosynthetic capacity was similar to that of ‘normal’ green leaves and promoted seed development.ConclusionsThe reversible leaf colour change in S. chinensis appears to be adaptive because it enhances pollination success during flowering, with a small photosynthetic cost, while re-greening of these leaves after flowering helps to meet the carbon requirements for seed development.
      PubDate: Tue, 09 Jan 2018 00:00:00 GMT
       
  • Increasing and declining native species in urban remnant grasslands
           respond differently to nitrogen addition and disturbance
    • Authors: Zeeman B; Morgan J.
      Abstract: Background and AimsAtmospheric nitrogen deposition and natural fire regime suppression are key drivers of vegetation change in urbanizing grasslands. Some species thrive under these conditions, while others face local extinction. In the natural grasslands that surround Melbourne, Australia, biotic homogenization has occurred with intensifying urbanization. Some native species have become rarer (decreaser species) across the landscape, while others have become more widespread (increaser species). This study experimentally examined the response of increaser and decreaser plant species to nitrogen addition/depletion, and examined the presence/absence of annual disturbance to the vegetation.MethodsDecreaser and increaser species were planted into 60 field plots established in an urban Melbourne grassland and examined over 2 years. Annual removal of above-ground biomass occurred in half the plots to simulate biomass removal via fire, with the remaining plots undisturbed. Soil nitrogen was depleted in one-third of plots, one-third received no nitrogen treatment and one-third were fertilized with nitrogen. Increaser plant species were predicted to persist in the absence of disturbance, and thrive when fertilized. In contrast, high mortality was predicted for decreaser species in the absence of disturbance, with fertilization providing no advantage.Key ResultsSeedling mortality for increaser and decreaser species was unrelated to the treatments. The mortality of decreaser species was high (69 %), and the mortality of increaser species low (20 %). However, seedling growth was related to the treatments. The total biomass of decreaser species was highest in annually disturbed plots, with growth suppressed in undisturbed plots. In contrast, the total biomass of increaser species was unrelated to the disturbance regime, but responded positively to nitrogen enrichment.ConclusionsThe results provide evidence that by affecting plant growth, declines in biomass removal and atmospheric nitrogen deposition could be key drivers of biotic homogenization in urban grasslands.
      PubDate: Tue, 09 Jan 2018 00:00:00 GMT
       
  • Strong population bottleneck and repeated demographic expansions of
           Populus adenopoda (Salicaceae) in subtropical China
    • Authors: Fan L; Zheng H, Milne R, et al.
      Abstract: Background and AimsGlacial refugia and inter-/postglacial recolonization routes during the Quaternary of tree species in Europe and North America are well understood, but far less is known about those of tree species in subtropical eastern Asia. Thus, we have examined the phylogeographic history of Populus adenopoda (Salicaceae), one of the few poplars that naturally occur in this subtropical area.MethodsGenetic variations across the range of the species in subtropical China were surveyed using ten nuclear microsatellite loci and four chloroplast fragments (matK, trnG-psbK, psbK-psbI and ndhC-trnV). Coalescent-based analyses were used to test demographic and migration hypotheses. In addition, species distribution models (SDMs) were constructed to infer past, present and future potential distributions of the species.Key ResultsThirteen chloroplast haplotypes were detected, and haplotype-rich populations were found in central and southern parts of the species’ range. STRUCTURE analyses of nuclear microsatellite loci suggest obvious lineage admixture, especially in peripheral and northern populations. DIYABC analysis suggests that the species might have experienced two independent rounds of demographic expansions and a strong bottleneck in the late Quaternary. SDMs indicate that the species’ range contracted during the Last Glacial Maximum (LGM), and contracted northward but expanded eastward during the Last Interglacial (LIG).ConclusionsChloroplast data and SDMs suggest that P. adenopoda might have survived in multiple glacial refugia in central and southern parts of its range during the LGM. Populations of the Yunnan–Guizhou Plateau in the southern part have high chloroplast DNA diversity, but may have contributed little to the postglacial recolonization of northern and eastern parts. The three major demographic events inferred by DIYABC coincide with the initiation of the LIG, start of the LGM and end of the LGM, respectively. The species may have experienced multiple rounds of range contraction during glacial periods and range expansion during interglacial periods. Our study corroborates the importance of combining multiple lines of evidence when reconstructing Quaternary population evolutionary histories.
      PubDate: Sat, 06 Jan 2018 00:00:00 GMT
       
  • Under pressure' Epicormic shoots and traumatic growth zones in
           high-latitude Triassic trees from East Antarctica
    • Authors: Decombeix A; Serbet R, Taylor E.
      Abstract: Background and AimsInvestigating the biology of trees that were growing at high latitudes during warmer geological periods is key to understanding the functioning of both past and future forest ecosystems. The aim of this study is to report the first co-occurrence of epicormic shoots and traumatic growth zones in fossil trees from the Triassic of Antarctica and to discuss their biological and environmental implications.MethodsPermineralized woods bearing scars of epicormic shoots were collected from the Triassic Fremouw Formation in Gordon Valley, Central Transantarctic Mountains, Antarctica in 2010. Samples from different portions of three specimens were prepared using standard thin section and hydrofluoric (HF) acid peel techniques, and anatomical details were studied in transmitted light.Key ResultsThe fossil woods represent the outer part of trunks, with at least 40 growth rings that are 0.2–4.8 mm in width. Anatomical comparisons suggest that they represent a new tree taxon for the Triassic of Antarctica. Numerous small epicormic shoots can be seen crossing the wood almost horizontally and are locally branched. Each specimen also contains several occurrences of traumatic growth zones located in the early wood, in the cells produced either at the very start of the growing season or slightly later.ConclusionsThis is the first report of epicormic shoots and traumatic growth zones in the wood of a Triassic tree from Antarctica. Their co-occurrence indicates that these trees from Gordon Valley were subjected to environmental stresses not seen in Triassic trees previously described from this region. This suggests that they had a different biology and/or were growing in a different habitat, which offers a new glimpse into the diversity of high-latitude trees in the Triassic greenhouse climate.
      PubDate: Sat, 06 Jan 2018 00:00:00 GMT
       
  • Mineralized trichomes in Boraginales: complex microscale heterogeneity and
           simple phylogenetic patterns
    • Authors: Mustafa A; Ensikat H, Weigend M.
      Abstract: Background and AimsBoraginales are often characterized by a dense cover of stiff, mineralized trichomes, which may act as a first line of defence against herbivores. Recent studies have demonstrated that the widely reported silica and calcium carbonate in plant trichomes may be replaced by calcium phosphate. The present study investigates mineralization patterns in 42 species from nine families of the order Boraginales to investigate detailed patterns of mineralization and the possible presence of a phylogenetic signal in different mineralization patterns.MethodsThe distribution of biominerals was analysed by scanning electron microscopy (SEM) including cryo-SEM and energy-dispersive X-ray analyses with element mapping. The observed distribution of biominerals was plotted onto a published phylogeny of the Boraginales. Three colours were selected to represent the principal elements: Si (red), Ca (green) and P (blue).Key ResultsCalcium carbonate was present in the mineralized trichomes of all 42 species investigated, silica in 30 and calcium phosphate in 25; multiple mineralization with calcium carbonate and silica or calcium phosphate was found in all species, and 13 of the species were mineralized with all three biominerals. Trichome tips featured the most regular pattern – nearly all were exclusively mineralized with either silica or calcium phosphate. Biomineralization of the trichome shafts and bases was found to be more variable between species. However, the trichome bases were also frequently mineralized with calcium phosphate or silica, indicating that not only the tip is under functional constraints requiring specific patterns of chemical heterogeneity. The complete absence of either silica or phosphate may be an additional feature with systematic relevance.ConclusionsThis study demonstrates that complex, site-specific and differential biomineralization is widespread across the order Boraginales. Calcium phosphate, only recently first reported as a structural plant biomineral, is common and appears to be functionally analogous to silica. A comparison with the phylogeny of Boraginales additionally reveals striking phylogenetic patterns. Most families show characteristic patterns of biomineralization, such as the virtual absence of calcium phosphate in Cordiaceae and Boraginaceae, the triple biomineralization of Heliotropiaceae and Ehretiaceae, or the absence of silica in Namaceae and Codonaceae. The complex chemical and phylogenetic patterns indicate that trichome evolution and functionalities are anything but simple and follow complex functional and phylogenetic constraints.
      PubDate: Sat, 06 Jan 2018 00:00:00 GMT
       
  • Patterns of nuclear and chloroplast genetic diversity and structure of
           manioc along major Brazilian Amazonian rivers
    • Authors: Alves-Pereira A; Clement C, Picanço-Rodrigues D, et al.
      Abstract: Background and AimsAmazonia is a major world centre of plant domestication, but little is known about how the crops were dispersed across the region. Manioc (Manihot esculenta) was domesticated in the south-western Amazon basin, and is the most important staple food crop that originated in Amazonia. Current contrasting distributions may reflect distinct histories of dispersal of bitter and sweet manioc landraces. To produce new insights into the evolutionary history of the crop, we investigated the contemporary genetic diversity and structure of bitter and sweet manioc along major Amazonian rivers.MethodsThe patterns of genetic structure and diversity of wild and cultivated sweet and bitter manioc with four chloroplast and 14 nuclear microsatellite markers were evaluated. Results were interpreted in terms of the crop’s dispersal.Key resultsNo phylogeographic patterns among rivers were detected, and genetic structure among rivers was confounded by the bitter–sweet divergence. However, differences in the distribution of nuclear diversity and somewhat distinctive patterns of genetic structure across rivers were observed within bitter and sweet manioc.ConclusionsVarious pre-Columbian and post-European conquest events in the history of Amazonian occupation may explain the absence of clearer patterns of genetic structure. However, the wide distribution of the most common chloroplast haplotype agrees with an early dispersal of manioc across Brazilian Amazonia. Furthermore, differences in genetic structure and in the spatial distribution of genetic diversity suggest that bitter and sweet manioc had distinct dispersal histories. Knowledge about how prehistoric and contemporary Amazonian peoples manage their crops is valuable for the maintenance and conservation of the impressive diversity of their native crops.
      PubDate: Thu, 04 Jan 2018 00:00:00 GMT
       
  • Critical temperature and precipitation thresholds for the onset of
           xylogenesis of Juniperus przewalskii in a semi-arid area of the
           north-eastern Tibetan Plateau
    • Authors: Ren P; Rossi S, Camarero J, et al.
      Abstract: Background and AimsThe onset of xylogenesis plays an important role in tree growth and carbon sequestration, and it is thus a key variable in modelling the responses of forest ecosystems to climate change. Temperature regulates the resumption of cambial activity, but little is known about the effect of water availability on the onset of xylogenesis in cold but semi-arid regions.MethodsThe onset of xylogenesis during 2009–2014 was monitored by weekly microcoring Juniperus przewalskii trees at upper and lower treelines on the north-eastern Tibetan Plateau. A logistic regression was used to calculate the probability of xylogenic activity at a given temperature and a two-dimensional reverse Gaussian model to fit the differences between the observed and estimated days of xylogenesis onset at given temperatures and precipitation within a certain time window.Key ResultsThe thermal thresholds at the beginning of the growing season were highly variable, suggesting that temperature was not the only factor initiating xylem growth under cold and dry climatic conditions. The onset of xylogenesis was well predicted for climatic thresholds characterized by a cumulative precipitation of 17.0 ± 5.6 mm and an average minimum temperature of 1.5 ± 1.4 °C for a period of 12 d.ConclusionsXylogenesis in semi-arid regions with dry winters and springs can start when both critical temperature and precipitation thresholds are reached. Such findings contribute to our knowledge of the environmental drivers of growth resumption that previously had been investigated largely in cold regions without water shortages during early growing seasons. Models of the onset of xylogenesis should include water availability to improve predictions of xylem phenology in dry areas. A mismatch between the thresholds of temperature and moisture for the onset of xylogenesis may increase forest vulnerability in semi-arid areas under forecasted warmer and drier conditions.
      PubDate: Fri, 29 Dec 2017 00:00:00 GMT
       
  • Pollination by fungus gnats and associated floral characteristics in five
           families of the Japanese flora
    • Authors: Mochizuki K; Kawakita A.
      Abstract: Background and aimsPollination by fungus gnats (Mycetophilidae and Sciaridae) is uncommon, but is nevertheless known to occur in 20 genera among eight angiosperm families. Because many fungus gnat-pollinated plants possess a dark red floral display, we hypothesized that fungus gnat pollination is more widespread among plants with similar floral display than currently known. We thus studied the pollination biology of flowers with dark red pigmentation in five families, focusing particularly on plants having small, flat, actinomorphic flowers with exposed nectaries and short stamens, because these floral characteristics mirror those of a known fungus gnat-pollinated genus (Mitella).MethodsWe observed daytime and night-time floral visitors for a total of 194.5 h in Aucuba japonica (Garryaceae), Euonymus spp. (Celastraceae), Disanthus cercidifolius (Hamamelidaceae), Micranthes fusca (Saxifragaceae) and Streptopus streptopoides (Liliaceae). Visitors were categorized into functional groups, and a pollination importance index (PII) was calculated for each functional group based on visitation frequency, pollen load and behaviour on flowers.Key resultsFungus gnats were dominant among the 1762 insects observed (36–92 % depending on the plant species) and were the most important pollinators among all plants studied (PII: 0.529–1). Fungus gnat visits occurred during the daytime and, more frequently, at dusk. Most often, pollen grains became clumped on the ventral side of the head and/or thorax as the short-proboscid fungus gnats foraged on nectar and came into contact with anthers located close to the flower base.ConclusionsPollination by fungus gnats is probably more common than previously thought, especially in habitats similar to those of the plants studied (moist forest understorey, streamside or subalpine meadow) where fungus gnats are abundant year-round. Our results further suggest that there may be a previously unnoticed association between fungus gnat pollination and dark red coloration, and a shared overall floral architecture among the plants studied.
      PubDate: Fri, 29 Dec 2017 00:00:00 GMT
       
  • Wheat genetic resources in the post-genomics era: promise and challenges
    • Authors: Rasheed A; Mujeeb-Kazi A, Ogbonnaya F, et al.
      Abstract: BackgroundWheat genetic resources have been used for genetic improvement since 1876, when Stephen Wilson (Transactions and Proceedings of the Botanical Society of Edinburgh 12: 286) consciously made the first wide hybrid involving wheat and rye in Scotland. Wide crossing continued with sporadic attempts in the first half of 19th century and became a sophisticated scientific discipline during the last few decades with considerable impact in farmers’ fields. However, a large diversity of untapped genetic resources could contribute in meeting future wheat production challenges.Perspectives and ConclusionRecently the complete reference genome of hexaploid (Chinese Spring) and tetraploid (Triticum turgidum ssp. dicoccoides) wheat became publicly available coupled with on-going international efforts on wheat pan-genome sequencing. We anticipate that an objective appraisal is required in the post-genomics era to prioritize genetic resources for use in the improvement of wheat production if the goal of doubling yield by 2050 is to be met. Advances in genomics have resulted in the development of high-throughput genotyping arrays, improved and efficient methods of gene discovery, genomics-assisted selection and gene editing using endonucleases. Likewise, ongoing advances in rapid generation turnover, improved phenotyping, envirotyping and analytical methods will significantly accelerate exploitation of exotic genes and increase the rate of genetic gain in breeding. We argue that the integration of these advances will significantly improve the precision and targeted identification of potentially useful variation in the wild relatives of wheat, providing new opportunities to contribute to yield and quality improvement, tolerance to abiotic stresses, resistance to emerging biotic stresses and resilience to weather extremes.
      PubDate: Tue, 12 Dec 2017 00:00:00 GMT
       
  • Exploring trees in three dimensions: VoxR, a novel voxel-based R package
           dedicated to analysing the complex arrangement of tree crowns
    • Authors: Lecigne B; Delagrange S, Messier C.
      Abstract: BackgroundInterest in tree form assessments using the terrestrial laser scanner (TLS) has increased in recent years. Yet many existing methods are limited to small-sized trees, principally due to noise and occlusion phenomena. In this paper, a novel voxel-based program that is dedicated to the analyses of large tree structures is presented. The method is based on the assumption that architectural trait variations (i.e. branching angle, bifurcation ratio, biomass allocation, etc.) influence the way a tree explores space. This method uses the concept of space exploration that considers a voxel as a portion of space explored by the tree. Once the TLS scene is voxelized, the program provides tools that extract qualitative (geometrical) and quantitative (volumetric) metrics. These tools measure (1) voxel dispersion in three dimensions (3-D), (2) projections of the voxel cloud in 2-D and (3) multi-temporal changes within a single tree crown.ScopeTo test algorithm capabilities of measuring larger tree architectural traits, two application studies were conducted using point clouds that were either generated by a tree growth simulation model, thereby allowing algorithm application in a perfectly controlled environment, or acquired in the field with a TLS device. The space exploration concept makes it possible to take advantage of the volumetric nature of voxels to compensate for occlusion. The hypothesis that large-sized voxels can be used to reduce occlusion in the original point cloud was tested, as well as the consequences of voxel size on quantification of tree volume and on precision of derived metrics.ConclusionsResults show that space exploration is well adapted to highlight architectural differences among trees. They also suggest that large-sized voxels are efficient for occlusion compensation at the expense of metrics precision in some cases. The best resolution to choose depending on the research objectives and quality of the TLS scan is discussed.
      PubDate: Thu, 07 Sep 2017 00:00:00 GMT
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
Home (Search)
Subjects A-Z
Publishers A-Z
Customise
APIs
Your IP address: 54.224.108.85
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-