H. Fatmi, S. Maalem, Bouchra Harsa, A. Dekak, Haroun Chenchouni
{"title":"Pollen morphological variability correlates with a large-scale gradient of aridity","authors":"H. Fatmi, S. Maalem, Bouchra Harsa, A. Dekak, Haroun Chenchouni","doi":"10.5194/we-20-19-2020","DOIUrl":null,"url":null,"abstract":"Abstract. The study of the morphology of living organisms is essential to understand\ntheir evolution and diversity. This study aims to determine the importance\nof climatic gradients in the diversity of pollen morphotypes using Atriplex halimus L.\n(Amaranthaceae) as a model species. Atriplex halimus is a perennial shrubby plant,\npolymorphic and very resistant to severe environmental conditions. In seven\nbioclimatic zones, ranging from mesic conditions in the north to\nhot–hyperarid in the south, pollen samples were collected from 49 sites,\nwith seven accessions per bioclimate. Under a light microscope, pollen grains\nwere selected and analyzed from three anthers of different flowers. Besides\nthe usual pollen grain types, some previously unknown morphotypes, such as\nsulcate, triangular, and ovoid, were observed and described at the different\nclimatic zones. A total of 10 pollen grain shapes were quantified and\ndiscussed following their specific occurrences within different climatic\nzones. Occurrence frequencies of different pollen shapes ranged between 0 %\nand 85.7 %, where the pantoporate spheroidal was the most widespread in\nall climatic zones, especially in the desert climate (85.7 %). Five\npollen types occurred exclusively once per climate zone. The pantoporate\nprolate spheroidal in mesomediterranean climate with a long dry season\n(28.6 %), sulcate in the xerothermomediterranean climate (14.3%),\npantoporate subtriangular in the subdesert climate with a short dry season\n(14.3 %), and pantoporate subprolate and boat-shaped in a subdesert\nclimate with a long dry season with 14.3 % for each. Our findings help to\nunderstand the evolutionary effects of climate gradients on pollen\nmorphology and variability in arid and desert areas and point towards a\nhigh degree of specialization in order to maximize trade-offs between\npollination efficiency and protection of pollen grains from dehydration.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2020-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"18","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Web Ecology","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.5194/we-20-19-2020","RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ECOLOGY","Score":null,"Total":0}
引用次数: 18
Abstract
Abstract. The study of the morphology of living organisms is essential to understand
their evolution and diversity. This study aims to determine the importance
of climatic gradients in the diversity of pollen morphotypes using Atriplex halimus L.
(Amaranthaceae) as a model species. Atriplex halimus is a perennial shrubby plant,
polymorphic and very resistant to severe environmental conditions. In seven
bioclimatic zones, ranging from mesic conditions in the north to
hot–hyperarid in the south, pollen samples were collected from 49 sites,
with seven accessions per bioclimate. Under a light microscope, pollen grains
were selected and analyzed from three anthers of different flowers. Besides
the usual pollen grain types, some previously unknown morphotypes, such as
sulcate, triangular, and ovoid, were observed and described at the different
climatic zones. A total of 10 pollen grain shapes were quantified and
discussed following their specific occurrences within different climatic
zones. Occurrence frequencies of different pollen shapes ranged between 0 %
and 85.7 %, where the pantoporate spheroidal was the most widespread in
all climatic zones, especially in the desert climate (85.7 %). Five
pollen types occurred exclusively once per climate zone. The pantoporate
prolate spheroidal in mesomediterranean climate with a long dry season
(28.6 %), sulcate in the xerothermomediterranean climate (14.3%),
pantoporate subtriangular in the subdesert climate with a short dry season
(14.3 %), and pantoporate subprolate and boat-shaped in a subdesert
climate with a long dry season with 14.3 % for each. Our findings help to
understand the evolutionary effects of climate gradients on pollen
morphology and variability in arid and desert areas and point towards a
high degree of specialization in order to maximize trade-offs between
pollination efficiency and protection of pollen grains from dehydration.
Web EcologyAgricultural and Biological Sciences-Ecology, Evolution, Behavior and Systematics
CiteScore
4.60
自引率
0.00%
发文量
6
审稿时长
17 weeks
期刊介绍:
Web Ecology (WE) is an open-access journal issued by the European Ecological Federation (EEF) representing the ecological societies within Europe and associated members. Its special value is to serve as a publication forum for national ecological societies that do not maintain their own society journal. Web Ecology publishes papers from all fields of ecology without any geographic restriction. It is a forum to communicate results of experimental, theoretical, and descriptive studies of general interest to an international audience. Original contributions, short communications, and reviews on ecological research on all kinds of organisms and ecosystems are welcome as well as papers that express emerging ideas and concepts with a sound scientific background.