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Tanta University (2023)

Biodiversity characteristics of the endoemic texa in Egyptian flora

El-Khalafy, Mohamed Mahmoud

Titre : Biodiversity characteristics of the endoemic texa in Egyptian flora

Auteur : El-Khalafy, Mohamed Mahmoud.

Etablissement de soutenance : Tanta University

Grade : Doctor of Philosophy (PhD) in Botany 2023

The present study aims to : update, verify the number and clarify the reasons for justifications of endemic taxa in the Egyptian flora, mention conservation categories of endemic taxa according to IUCN categories, detect the services and goods offered by them, clarify the most serious threats that impacted them, describe their pollen grains and seeds using light and scanning electron microscope, study some of their molecular characteristics using DNA barcoding, design their distribution using grid map analysis, and study their relationship with the associated plant species and communities and the edaphic and environmental factors. Twenty field visits were conducted from spring 2018 to spring 2022 to many locations all over Egypt. The total number of endemic taxa was 41, belonging to 37 genera and 19 families distributed in ten habitats. Thirty-five taxa had a distribution in only one phytogeographical region, while the remaining taxa had a wide distribution in two or more regions. The most represented dispersal types were the ballochores and pogonochores, while the less represented were desmochores and pterochores. There was a gradual increase in the frequency of the flowered endemic taxa form December till May. The most represented good was the medicinal uses, while gathering terrestrial plants and drought were the most represented threats. Thirty-two taxa of the endemics are threatened according to IUCN categories (8 critically endangered, 15 endangered and 10 extinct), while 8 taxa are data deficient. The complete IUCN assessment for each species was provided in the present study. The application of TWINSPAN on the cover estimates of 1026 species (21 endemic species and 1005 associated) led to the recognition of 8 vegetation groups at the 4th level of classification. The pollen grains and seeds of the endemic taxa were described using light and scanning electron microscope. In addition, artificial keys based on the most obvious characters were used for confirmation of its identification. Two genes (rbcL and matK) were amplified for each species. rbcL identified 10 out of 26 species at the species level and 15 species at the genus level. In addition, matK identified 8 out of 26 species at the species level and 17 species at the genus level. On the other hand, rbcL barcode failed partially to identify Bufonia multiceps, and matK barcode failed to identify Ifloga spicata subsp. elbaensis, as these species were identified at the family level.

Présentation étendue (EULC)

Page publiée le 10 mars 2023