Thèse : Sciences : Université, Faculté des sciences de Paris : 1841. / Titre provenant de l'écran-titre.

Ce travail de thèse s'inscrit dans un projet régional, initié par le Parc du Lubéron et en collaboration avec le Laboratoire de Pharmacognosie et d'Ethnopharmacologie de l’Université de Marseille. Il avait pour objectif d'étudier la possibilité de domestiquer une plante sauvage, Inula montana L. (Asteraceae) connue dans la pharmacopée provençale pour ses effets anti traumatiques semblables à ceux d'Arnica montana L. et de la proposer comme nouvelle production agricole. Inula montana produit notamment des lactones sesquiterpènes, identifiées comme les métabolites secondaires responsables de ses aptitudes biologiques anti inflammatoires. Il s’est agit dans cette étude1) de déterminer les caractéristiques de croissance et de développement de la plante sauvage largement inconnue et d’identifier en conditions naturelles les facteurs les plus favorables à la production de métabolites secondaires, 2)d’étudier sa capacité à se multiplier végétativement in vitro et à former des cultures cellulaires aptes à synthétiser les molécules d’intérêt 3), de proposer un itinéraire technique applicable agronomiquement et 4) de tester les effets de divers facteurs environnementaux (fertilisation, apport de NaCl, modification du rythme circadien de l’éclairement,rayonnement UVB, ablation de feuilles, application de méthyl jasmonate ) sur la production qualitative et quantitative des lactones sesquiterpènes et des composés phénoliques. Les traits phénologiques de la plante sauvage sont impactés par l’altitude qui induit un retard dans la croissance végétative et la phase reproductrice ainsi que des modifications physiologiques et morphologiques. Les teneurs en métabolites secondaires (certaines lactones sesquiterpènes, les polyphénols totaux et flavonoïdes) varient en fonction de la saison et sont plus importantes dans le site qui présente les conditions climatiques les plus contraignantes du point de vue hydrique (sol drainant,température plus élevée et présence d’une période sèche en été). L’observation microscopique a indiqué la présence de deux types de trichomes : glandulaires (bisériés) et non glandulaires (des poils) qui sont potentiellement les structures porteuses des molécules d’intérêt. I. montana est apte à former des cals in vitro à partir d’explants racinaires, foliaires et caulinaires sur lesquels des pousses feuillées se forment. La domestication d’Inula a été réussie à partir de semences issues des plantes sauvages et en conditions agronomiques, les teneurs en lactones sesquiterpènes (costunolide, artémorine, eldarine et hydrocostunolide) et en composés phénoliques sont généralement plus élevées que chez les plantes sauvages. Les différentes contraintes appliquées pour tester les effets des facteurs environnementaux sur la production des métabolites ont montré : 1) qu’il ne peut pas être établi de corrélation entre la présence d’un stress oxydatif et une augmentation des teneurs en métabolites chez Inula 2) que l’accumulation des lactones et composés phénoliques semblent principalement favorisée lorsque la plante dispose d’un surplus de squelettes carbonés, non utilisés pour la croissance 3) enfin, les deux conditions les plus favorables à l’accumulation des métabolites chez Inula, sont : dans les feuilles, une alternance rapide de lumière et d’obscurité durant la photopériode et dans les capitules, l’application de méthyl jasmonate. Ce travail augure de bonnes perspectives en termes de valorisation d’Inula dans le secteur pharmaco-cosmétologique. Il reste à poursuivre la description du profil phytochimique de la plante et à localiser précisément les organes et/ou sous structures anatomiques concentrant les composés considérés. Ayant démontré que cette plante présente une bonne réponse à la domestication, il est également proposé de poursuivre l’étude des leviers environnementaux susceptibles d’influencer positivement et significativement le profil chimique d’Inula. / This thesis work is part of a regional project, initiated by the Luberon Park and in collaboration with the Laboratory of Pharmacognosy and Ethnopharmacology of the University of Marseille. It aimed to study the possibility of domesticating a wild plant, Inula montana L. (Asteraceae) known in the Provençal pharmacopoeia for its anti-traumatic effects similar to those of Arnica montana L. and to propose it as a new agricultural production. Inula montana produces lactones sesquiterpenes, identified as the secondary metabolites responsible for its biological anti-inflammatory properties. In this study, 1) to determine the growth and development characteristics of the largely unknown wild plant and to identify under natural conditions the most favorable factors for the production of secondary metabolites, 2) to study its characteristics. ability to multiply vegetatively in vitro and to form cell cultures able to synthesize the molecules of interest 3), to propose an agronomically applicable technical itinerary and 4) to test the effects of various environmental factors (fertilization, NaCl supply, modification circadian rhythm of illumination, UVB radiation, ablation of leaves, application of methyl jasmonate) on the qualitative and quantitative production of sesquiterpene lactones and phenolic compounds. The phenological characteristics of the wild plant are impacted by the altitude which induces a delay in the vegetative growth and the reproductive phase as well as physiological and morphological modifications. Levels of secondary metabolites (certain sesquiterpene lactones, total polyphenols and flavonoids) vary according to the season and are more important in the site which has the most water-constraining climatic conditions (draining soil, higher temperature and presence of a dry period in summer). Microscopic observation indicated the presence of two types of trichomes: glandular (biseriate) and non-glandular (hair) which are potentially the carrying structures of the molecules of interest. I. montana is able to form calli in vitro from root, foliar and shoot explants on which leafy shoots are formed. The domestication of Inula has been successful from seed from wild plants and under agronomic conditions, sesquiterpene lactone (costunolide, artemorine, eldarin and hydrocostunolide) and phenolic compounds are generally higher than in wild plants. The different constraints applied to test the effects of environmental factors on the production of metabolites have shown: 1) that there can be no correlation between the presence of oxidative stress and an increase in metabolite levels in Inula 2) that the accumulation of lactones and phenolic compounds seems mainly favored when the plant has a surplus of carbon skeletons, not used for growth; 3) finally, the two most favorable conditions for the accumulation of metabolites in Inula, are: in the leaves, a rapid alternation of light and darkness during the photoperiod and in the flower heads, the application of methyl jasmonate. This work augurs good prospects in terms of valuation of Inula in the pharmaco-cosmetological sector. It remains to continue the description of the phytochemical profile of the plant and to precisely locate the organs and / or anatomical substructures concentrating the compounds in question. Having demonstrated that this plant has a good response to domestication, it is also proposed to continue the study of environmental levers likely to positively and significantly influence the chemical profile of Inula.

<p>Komparativnom&nbsp; analizom&nbsp; morfo-anatomskih&nbsp; i mikromorfolo&scaron;kih&nbsp; karakteristika&nbsp; lista,&nbsp; stabla,&nbsp; rizoma,&nbsp; korena, ploda&nbsp; i&nbsp; receptakuluma,&nbsp; kao&nbsp; i&nbsp; biohemijskom&nbsp; analizom&nbsp; etarskih ulja&nbsp; podzemnih&nbsp; organa,&nbsp; obuhvaćeno&nbsp; je&nbsp; ukupno&nbsp; 16&nbsp; vrsta&nbsp; iz&nbsp; 4<br />roda,&nbsp; Inula&nbsp; (I. aschersoniana,&nbsp; I. bifrons,&nbsp; I. britannica,&nbsp;<em> I. conyza, I.&nbsp; ensifolia,&nbsp; I.&nbsp; germanica,&nbsp; I.&nbsp; helenium,&nbsp; I.&nbsp; oculus-christi,&nbsp; I. saslicina&nbsp; ssp.&nbsp; salicina,&nbsp; I.&nbsp; salicina&nbsp; ssp.&nbsp; aspera,&nbsp; I.&nbsp; spiraeifolia), Dittrichia&nbsp; (D.&nbsp; graveolens,&nbsp; D.&nbsp; viscosa),&nbsp; Limbarda&nbsp; (L.<br />crithmoides)&nbsp; i&nbsp; Pulicaria&nbsp; (P. dysenterica,&nbsp; P. vulgaris) iz</em> tribusa Inuleae,&nbsp; familije&nbsp; Compositae.&nbsp; Vrste&nbsp; iz&nbsp; različitih&nbsp; rodova analizirane&nbsp; u&nbsp; ovoj&nbsp; disertaciji&nbsp; ranijom&nbsp; klasifikacijom&nbsp; svrstavane su u okviru različitih sekcija roda&nbsp; Inula, a takođe i tipska vrsta ovog roda,<em> I. helenium L</em>., svrstavana je u okviru zasebne sekcije<em> Corvisartia.</em>&nbsp; Na&nbsp; osnovu&nbsp; najnovijih&nbsp; molekularnih&nbsp; filogenetskih analiza, baziranih na sekvencama plastidne i jedarne DNK, kao i na osnovu morfolo&scaron;kih i kariolo&scaron;kih podataka, predloženo je da sekcija&nbsp; <em>Corvisartia&nbsp;</em> bude&nbsp; izdvojena&nbsp; u&nbsp; zaseban&nbsp; rod.&nbsp; Ciljevi&nbsp; ove<br />disertacije definisani su u skladu sa činjenicom da su podaci o morfo-anatomskoj,&nbsp; mikromorfolo&scaron;koj&nbsp; i&nbsp; biohemijskoj&nbsp; građi vegetativnih&nbsp; i&nbsp; reproduktivnih&nbsp; organa&nbsp; vrsta&nbsp; ovog&nbsp; tribusa malobrojni&nbsp; i&nbsp; nepotpuni,&nbsp; dok&nbsp; su&nbsp; analize&nbsp; vr&scaron;ene&nbsp; parcijalno&nbsp; i<br />nezavisno&nbsp; kod&nbsp; pojedinih&nbsp; predstavnika,&nbsp; sa&nbsp; slabim&nbsp; akcentom&nbsp; na njihovu&nbsp; komparativnu&nbsp; analizu.&nbsp; Istraživanje&nbsp; je&nbsp; obuhvatilo&nbsp; veliki broj kvalitativnih i kvantitativnih karaktera koji su analizirani i mereni&nbsp; pomoću&nbsp; stereomikroskopa,&nbsp; svetlosnog,&nbsp; fluorescentnog&nbsp; i skening elektronskog mikroskopa. Dobijeni podaci statistički su obrađeni&nbsp; različitim&nbsp; metodama&nbsp; numeričke&nbsp; analize&nbsp; koje&nbsp; se&nbsp; inače<br />koriste pri taksonomskim istraživanjima.&nbsp; Ovakav tip analize za vrste&nbsp; rodova&nbsp;<em> Inula,</em>&nbsp; <em>Dittrichia,&nbsp; Limbarda&nbsp; i&nbsp; Pulicaria</em>&nbsp; nije&nbsp; zabeležen u dosada&scaron;njoj literaturi.<br />Sprovedena&nbsp; analiza&nbsp; pokazala&nbsp; je&nbsp; da&nbsp; ni&nbsp; jedan&nbsp; vegetativni&nbsp; biljni organ&nbsp; pojedinačno&nbsp; ne&nbsp; pruža&nbsp; dovoljno&nbsp; informacija&nbsp; na&nbsp; osnovukojih bi se sa statističkom sigurno&scaron;ću mogle izdvojiti određene grupe&nbsp; vrsta,&nbsp; niti&nbsp; rodovi&nbsp; prema&nbsp; postojećoj&nbsp; podeli.&nbsp; U&nbsp; okviru analiziranih anatomskih i mikromorfolo&scaron;kih karakteristika ploda i&nbsp; receptakuluma,&nbsp; organizacija&nbsp; sklerenhimskog&nbsp; tkiva&nbsp; u&nbsp; zrelom plodu i karakteristike receptakuluma predstavljaju karaktere koji su dijagnostički za rodove. Karakteri koji razdvajaju analizirane taksone&nbsp; jesu:&nbsp; karakteristike&nbsp; papusa&nbsp; kod&nbsp; vrsta&nbsp; roda&nbsp;<em> Pulicaria; </em>prstenasato&nbsp; suženje&nbsp; između&nbsp; baze&nbsp; papusa&nbsp; i&nbsp; cipsele,&nbsp; organizacija<br />sklerenhimskog&nbsp; tkiva&nbsp; ploda&nbsp; i&nbsp; tip&nbsp; trihoma&nbsp; na&nbsp; povr&scaron;ini receptakuluma&nbsp; kod&nbsp; vrsta&nbsp; roda<em>&nbsp; Dittrichia</em>;&nbsp; sekretorni&nbsp; kanali&nbsp; u perikarpu&nbsp; ploda,&nbsp; odsustvo&nbsp; trihoma&nbsp; i&nbsp; slabo&nbsp; izražena&nbsp; rebra&nbsp; na povr&scaron;ini&nbsp; receptakuluma&nbsp; kod&nbsp; vrste<em>&nbsp; L.&nbsp; crithmoides</em>.&nbsp; Plod&nbsp; vrste&nbsp;<em> I.</em><br /><em>helenium</em>&nbsp; razlikuje&nbsp; se&nbsp; od&nbsp; plodova&nbsp; svih&nbsp; preostalih&nbsp; analiziranih vrsta na osnovu njegovih dimenzija, većeg broja sklerenhimskih vrpci koje nisu istaknute u rebra, kao i na osnovu slabo izraženih rebara&nbsp; na&nbsp; receptakulumu,&nbsp; između&nbsp; karpopodijalnih&nbsp; otisaka,&nbsp; na kojima&nbsp; se&nbsp; nalaze&nbsp; žlezdane&nbsp; i&nbsp; nežlezdane&nbsp; trihome.&nbsp; Rezultati&nbsp; su<br />ukazali na&nbsp; to da se&nbsp; vrsta&nbsp; I. helenium&nbsp; izdvaja kao zaseban takson na osnovu anatomskih i mikromorfolo&scaron;kih karakteristika ploda i receptakuluma&nbsp; sa&nbsp; jednako&nbsp; malim&nbsp; stepenom&nbsp; statističke&nbsp; podr&scaron;ke koji&nbsp; takođe&nbsp; podržava&nbsp; izdvajanje&nbsp; rodova&nbsp; <em>Dittrichia,&nbsp; Limbarda&nbsp; i Pulicaria</em>&nbsp; u&nbsp; zasebne&nbsp; rodove.&nbsp; Stoga,&nbsp; na&scaron;i&nbsp; rezultati&nbsp; podržavaju tvrdnju&nbsp; da&nbsp; vrsta&nbsp; I.&nbsp; helenium&nbsp; treba&nbsp; biti&nbsp; izdvojena&nbsp; od&nbsp; preostalih<br />vrsta&nbsp; roda&nbsp; Inula&nbsp; u&nbsp; zaseban&nbsp; rod,&nbsp; pri&nbsp; čemu&nbsp; je&nbsp; njena&nbsp; autentičnost evidentna na nivou&nbsp; anatomije i mikromorfologije&nbsp; vegetativnih i reproduktivnih organa.<br />Rezultati&nbsp; hemijske&nbsp; analize&nbsp; etarskog&nbsp; ulja&nbsp; pružili&nbsp; su&nbsp; do&nbsp; sada nepoznate&nbsp; podatke&nbsp; o&nbsp; kvalitativnom&nbsp; i&nbsp; kvantitativnom&nbsp; sastavu etarskog ulja podzemnih organa analiziranih taksona i ukazali na mogućnost njihove primene u taksonomiji ispitivanog tribusa&nbsp; na nivou&nbsp; identifikacije&nbsp; pojedinačnih&nbsp; taksona.&nbsp; Takođe,&nbsp; dobijeni<br />rezultati&nbsp; ukazali&nbsp; su&nbsp; na&nbsp; nove&nbsp; potencijalno&nbsp; lekovite&nbsp; vrste&nbsp; koje predstavljaju&nbsp; potencijalni&nbsp; resurs&nbsp; za&nbsp; farmaceutsku&nbsp; industriju. Rezultati&nbsp; analize&nbsp; osnovnih&nbsp; komponenti&nbsp; kao&nbsp; i&nbsp; rezultati korespodentne&nbsp; analize&nbsp; ukazali&nbsp; su&nbsp; na&nbsp; odsustvo&nbsp; tendencije grupisanja&nbsp; taksona&nbsp; koji&nbsp; pripadaju&nbsp; istom&nbsp; rodu&nbsp; prema&nbsp; trenutno<br />važećoj&nbsp; klasifikaciji.&nbsp; Zbog&nbsp; velike&nbsp; varijabilnosti&nbsp; uslovljene faktorima&nbsp; spolja&scaron;nje&nbsp; sredine&nbsp; sastav&nbsp; etarskih&nbsp; ulja&nbsp; ne&nbsp; može&nbsp; se koristiti&nbsp; samostalno&nbsp; kao&nbsp; pouzdan&nbsp; hemotaksonomski&nbsp; marker. Ipak,&nbsp; rezultati&nbsp; o&nbsp; sastavu&nbsp; etarskih&nbsp; ulja&nbsp; značajni&nbsp; su&nbsp; u&nbsp; smislu njihove&nbsp; primene&nbsp; u&nbsp; medicinske&nbsp; i&nbsp; kozmetičke&nbsp; svrhe,&nbsp; u&nbsp; industriji<br />gde se etarska ulja koriste kao sirovina, te su dobijeni rezultati značajni&nbsp; i&nbsp; u&nbsp; kontekstu&nbsp; evaluacije&nbsp; kvaliteta&nbsp; etarskih&nbsp; ulja ispitivanih vrsta.<br />Sprovedeno&nbsp; istraživanje&nbsp; daje&nbsp; značajan&nbsp; doprinos&nbsp; u&nbsp; pogledu tačnije&nbsp; klasifikacije&nbsp; unutar&nbsp; tribusa&nbsp; koja&nbsp; se&nbsp; danas&nbsp; bazira uglavnom&nbsp; na&nbsp; morfolo&scaron;kim&nbsp; karakteristikama.&nbsp; Detaljno&nbsp; opisani morfo-anatomski&nbsp; i&nbsp; mikromorfolo&scaron;ki&nbsp; karakteri&nbsp; analiziranih<br />vegetativnih&nbsp; i&nbsp; reproduktivnih&nbsp; organa&nbsp; doprinose&nbsp; boljem poznavanju&nbsp; karakteristika&nbsp; vrsta&nbsp; analiziranih&nbsp; rodova&nbsp; i predstavljaju&nbsp; dopunu&nbsp; postojećim&nbsp; podacima&nbsp; o&nbsp; analiziranimtaksonima.&nbsp; Takođe,&nbsp; na&nbsp; bazi&nbsp; morfo-anatomskih&nbsp; karakteristika ploda i receptakuluma izrađen je dihotomi ključ za determinaciju analiziranih rodova i vrsta. Kori&scaron;ćenjem metoda diskriminantne i korespodentne analize izdvojeni su i karakteri na osnovu kojih je moguće&nbsp; izvr&scaron;iti&nbsp; diskriminaciju&nbsp; određenih&nbsp; grupa&nbsp; u&nbsp; okviru<br />analiziranih taksona.</p> / <p>A&nbsp; comparative&nbsp; analysis&nbsp; of&nbsp; morpho-anatomical&nbsp; and micromorphological characteristics of leaf, stem, rhizome, root, fruit and receptacle, as well as biochemical analysis of essential oils of underground organs, was conducted over 16 species of 4 genera,&nbsp;<em> Inula&nbsp; (I.&nbsp; aschersoniana,&nbsp; I.&nbsp; bifrons,&nbsp; I.&nbsp; britannica,&nbsp; I.conyza, I. ensifolia, I. germanica, I. helenium, I. oculus-christi, I. saslicina ssp. salicina, I. salicina ssp. aspera, I. spiraeifolia), Dittrichia&nbsp; (D.&nbsp; graveolens,&nbsp; D.&nbsp; viscosa),&nbsp; Limbarda&nbsp; (L. crithmoides)&nbsp; and&nbsp; Pulicaria&nbsp; (P.&nbsp; dysenterica,&nbsp; P.&nbsp; vulgaris)</em>&nbsp; tribe Inuleae,&nbsp; Compositae.&nbsp; In&nbsp; addition&nbsp; to&nbsp; the&nbsp; fact&nbsp; that&nbsp; the&nbsp; species from&nbsp; different&nbsp; genera&nbsp; analysed&nbsp; in&nbsp; this&nbsp; paper&nbsp; were&nbsp; previously placed&nbsp; in different sections within&nbsp; <em>Inula,&nbsp; I. helenium&nbsp; L</em>., as the type&nbsp; species&nbsp; of&nbsp; the&nbsp; genus&nbsp;<em> Inula,</em>&nbsp; has&nbsp; also&nbsp; been&nbsp; placed&nbsp; in&nbsp; a separate section&nbsp; Corvisartia.&nbsp; According to the latest molecular phylogenetic&nbsp; analyses,&nbsp; based&nbsp; on&nbsp; plastid&nbsp; and&nbsp; nuclear&nbsp; DNA sequence data, as well as morphological and karyological data, it&nbsp; is&nbsp; suggested&nbsp; that&nbsp; section&nbsp; Corvisartia&nbsp; should&nbsp; be&nbsp; segregated from&nbsp; the&nbsp; remaining&nbsp; Inula&nbsp; species&nbsp; as&nbsp; a&nbsp; separate&nbsp; genus,&nbsp; thus achieving&nbsp; a&nbsp; greater&nbsp; morphological&nbsp; homogeneity&nbsp; of&nbsp; the&nbsp; genus <em>Inula.&nbsp;</em> The objectives of dissertation are defined in accordance with&nbsp; the&nbsp; fact&nbsp; that&nbsp; the&nbsp; data&nbsp; on&nbsp; the&nbsp; morpho-anatomical, micromorphological and biochemical structure of the vegetative and reproductive organs of species of examined tribe are sparse and&nbsp; incomplete,&nbsp; while&nbsp; the&nbsp; analyses&nbsp; were&nbsp; carried&nbsp; out&nbsp; on&nbsp; few species&nbsp; of&nbsp; <em>Inula,&nbsp; Pulicaria,&nbsp; Dittrichia</em>&nbsp; and<em>&nbsp; Limbarda</em>,&nbsp; but&nbsp; less emphasis&nbsp; was&nbsp; placed&nbsp; on&nbsp; comparative&nbsp; purpose.&nbsp; The&nbsp; research involved&nbsp; a&nbsp; large&nbsp; number&nbsp; of&nbsp; qualitative&nbsp; and&nbsp; quantitative characters&nbsp; that&nbsp; were&nbsp; analysed&nbsp; and&nbsp; measured&nbsp; using&nbsp; a stereomicroscope,&nbsp; light,&nbsp; fluorescent&nbsp; and&nbsp; scanning&nbsp; electron microscope.&nbsp; The&nbsp; obtained&nbsp; data&nbsp; were&nbsp; statistically&nbsp; processed&nbsp; by various numerical analysis methods&nbsp; usually&nbsp; used in taxonomic research. These types&nbsp; of analyses for the species of the generaInula<em>,&nbsp; Dittrichia,&nbsp; Limbard&nbsp;</em> and&nbsp;<em> Pulicaria&nbsp;</em> have&nbsp; not&nbsp; been recorded in the literature so far. The&nbsp; conducted&nbsp; analysis&nbsp; showed&nbsp; that&nbsp; vegetative&nbsp; organs&nbsp; do&nbsp; not provide&nbsp; enough&nbsp; information&nbsp; on&nbsp; the&nbsp; basis&nbsp; of&nbsp; which&nbsp; certain groups&nbsp; of&nbsp; species&nbsp; could&nbsp; be&nbsp; singled&nbsp; out&nbsp; with&nbsp; statistically significant&nbsp; suport,&nbsp; neither&nbsp; the&nbsp; genera&nbsp; according&nbsp; to&nbsp; the&nbsp; actual classification.&nbsp; The&nbsp; yielded&nbsp; results&nbsp; indicated&nbsp; that&nbsp; the&nbsp; species from&nbsp; different&nbsp; genera&nbsp; were&nbsp; clearly&nbsp; delimited&nbsp; on&nbsp; the&nbsp; basis&nbsp; of their&nbsp; carpological&nbsp; and&nbsp; receptacular&nbsp; micromorphological&nbsp; and anatomical characteristics. Receptacle features and organisation of&nbsp; sclerenchyma&nbsp; tissue&nbsp; in&nbsp; a&nbsp; fruit&nbsp; are&nbsp; traits&nbsp; that&nbsp; tend&nbsp; to&nbsp; be diagnostic for genera. The features that separate analysed taxa&nbsp; are:&nbsp; two&nbsp; rows&nbsp; of&nbsp; pappus&nbsp; hairs&nbsp; in&nbsp;<em> Pulicaria&nbsp; </em>species;&nbsp; the&nbsp; ring constriction&nbsp; of&nbsp; the&nbsp; fruit&nbsp; over&nbsp; which&nbsp; it&nbsp; passes&nbsp; into&nbsp; pappus,&nbsp; the sclerenchymatous tissue in fruit in form&nbsp; of continuous ring, the type&nbsp; of&nbsp; trichomes&nbsp; on&nbsp; the&nbsp; receptacular&nbsp; surface&nbsp; in&nbsp;<em> Dittrichia </em>species;&nbsp; the&nbsp; fruit&nbsp; with&nbsp; secretory&nbsp; ducts,&nbsp; and&nbsp; the&nbsp; receptacular surface&nbsp; with&nbsp; weakly&nbsp; pronounced&nbsp; ridges&nbsp; without&nbsp; glands&nbsp; in&nbsp; L. crithmoides.&nbsp; I. helenium&nbsp; fruits differ from those of all the other species&nbsp; by&nbsp; their&nbsp; size,&nbsp; greater&nbsp; number&nbsp; of&nbsp; inconspicuous sclerenchymatic&nbsp; bundles,&nbsp; and&nbsp; poorly&nbsp; expressed&nbsp; ridges&nbsp; among carpopodial prints&nbsp; with glandular and non-glandular trichomes distributed along them. Results revealed that I. helenium&nbsp; stands out&nbsp; as&nbsp; a&nbsp; separate&nbsp; taxon,&nbsp; based&nbsp;&nbsp; on&nbsp; the&nbsp; anatomical&nbsp; and micromorphological&nbsp; characteristics&nbsp; of&nbsp; its&nbsp; fruit&nbsp; and&nbsp; receptacle, with equally small percentage of statistical support, which also supports the recognition of<em> Pulicaria,&nbsp;</em> <em>Dittrichia</em> and<em> Limabarda</em> as&nbsp; separate&nbsp; genera.&nbsp; Obtained&nbsp;&nbsp; results&nbsp; support&nbsp; the&nbsp; claim&nbsp; that&nbsp; I. helenium should be separated from the Inula genus, whereby its authenticity&nbsp; is&nbsp; evident&nbsp; at&nbsp; the&nbsp; level&nbsp; of&nbsp; anatomy&nbsp; and&nbsp; micromorphology of vegetative and reproductive organs. The chemical analysis of the essential oil has provided new&nbsp; data on the qualitative and quantitative composition of the essential oil of the&nbsp; underground organs of the analysed taxa&nbsp; and pointed out&nbsp; the&nbsp; possibility&nbsp; of&nbsp; their&nbsp; application&nbsp; in&nbsp; taxonomy.&nbsp; Also,&nbsp; the obtained results indicated potentially&nbsp; new medicinal plants that represent&nbsp; a&nbsp; potential&nbsp; resource for the&nbsp; pharmaceutical&nbsp; industry. Principal&nbsp; component&nbsp; analysis&nbsp; as&nbsp; well&nbsp; as&nbsp; the&nbsp; results&nbsp; of&nbsp; the Correspondent&nbsp; analysis&nbsp; indicated&nbsp; the&nbsp; absence&nbsp; of&nbsp; the&nbsp; grouping tendency of taxa belonging to the same genus,&nbsp; according to the actual classification. Due to the high variability conditioned by the&nbsp; environmental&nbsp; factors&nbsp; the&nbsp; composition&nbsp; of&nbsp; essential&nbsp; oils cannot&nbsp; be&nbsp; used&nbsp; independently&nbsp; as&nbsp; a&nbsp; reliable&nbsp; chemotaxonomic&nbsp; marker.&nbsp; However,&nbsp; the&nbsp; results&nbsp; of&nbsp; the&nbsp; composition&nbsp; of&nbsp; essential oils are significant in terms of their application for medical and cosmetic&nbsp; purposes, in the industry&nbsp; where&nbsp; oils&nbsp; are&nbsp; used&nbsp; as raw materials,&nbsp; and&nbsp; the&nbsp; results&nbsp; obtained&nbsp; are&nbsp; also&nbsp; significant&nbsp; in&nbsp; the context&nbsp; of&nbsp; evaluation&nbsp; of&nbsp; the&nbsp; quality&nbsp; of&nbsp; investigated&nbsp; essential oils.The&nbsp; conducted&nbsp; research&nbsp; makes&nbsp; a&nbsp; significant&nbsp; contribution&nbsp; to more precise classification within the&nbsp; tribe, which is now basedmainly&nbsp; on&nbsp; morphological&nbsp; characteristics.&nbsp; The&nbsp; detailed description&nbsp; of&nbsp; morpho-anatomical&nbsp; and&nbsp;&nbsp; micromorphological characters&nbsp; of&nbsp; the&nbsp; analysed&nbsp; vegetative&nbsp; and&nbsp; reproductive&nbsp; organs contributes&nbsp; to&nbsp; better&nbsp; knowledge&nbsp; of&nbsp; the&nbsp; characteristics&nbsp; of&nbsp; the analysed&nbsp; species&nbsp; and&nbsp; complements&nbsp; the&nbsp; existing&nbsp; data&nbsp; on&nbsp; them. Also, on the basis of morpho-anatomical characteristics of the fruit and the receptacle a dichotomous key&nbsp; for the determination of the analysed genera and species&nbsp; was developed. According to&nbsp; the&nbsp; Discriminant&nbsp; and&nbsp; Correspodent&nbsp; analysis&nbsp; the characteristics&nbsp; on&nbsp; which&nbsp; is&nbsp; possible&nbsp; to&nbsp; discriminate&nbsp; certain groups within the analysed genera are also distinguished.</p>