Air Pollution Effects on the Leaf Structure of some Fabaceae Species

Plants growing in the industrial areas and near the major roads absorb the pollutants at their foliar surface. In this paper, histological changes induced by air pollutants (from a cement factory combined with the pollution generated by human activities) in Lotus corniculatus L., Trifolium montanum L., T. pratense L. and T. repens L. leaves were followed. Some plant species have been identified to be able to absorb, detoxify and tolerate high levels of pollution. The tolerance degree is indirectly correlated with the intensity of injuries that occur in plant structure. Leaf thickness, the height of palisade cells, the diameter of the spongy cells, height and width of the upper epidermis cells, the thickness of the external wall of the upper epidermis cells, stomata length and stomatal index number of these species from highly polluted sites and lowly polluted sites were investigated by light microscopy. The stomata decrease in size and increase in density in leaves from high polluted sites. In the mesophyll cells (both in palisade and in spongy parenchyma) dark phenolic deposits could be observed

MICROMORPHOLOGICAL ASPECTS REGARDING THE LEAVES ON SOME ROSES WITH EMPHASIS ON SECRETORY GLANDS

The multicellular glands, the epicuticular wax and the tector hairs observed on the leaves are influenced usually by genetic constitution.The paper investigating 8 genetically related varieties: ‘Foc de Tabara’, ’Luchian’ ‘Paprika’, ‘Coup De Foudre’, ‘Independence’, ‘M-me A. Meilland’, ‘Cocktail’, ‘Laminuette’.The micromorphological studies evidencing some characters with a certain value for diagnosis. These may be used in investigation concerning to the identification when the flower is absent. Our study underlines micromorphology aspects of glands, epicuticular wax and tector hairs. All of them were been examinating through scanning electron microscopy method

SCANNING ELECTRON MICROSCOPY INVESTIGATIONS REGARDING Adonis vernalis L. FLOWER MORPHOLOGY

Abstract: The floral morphology of Adonis vernalis L. was observed with a scanning electron microscope (SEM). The investigations are important to clarify some taxonomical problems and also could provide useful diagnostic elements for the identification of this medicinal plant in powdered materials. All floral organs are initiated spirally and centripetally and develop centripetally. The petals (8-12) are shorter than the sepals (5-6) in early developmental stages. The petals are disposed on spiral (with 3-4 whorls). The stamens (numerous) are unbranched and reach maturity centripetally; they are free of the perianth. The anther walls consisting of a single layer epidermis in the anther wall surrounding the sporagenous tissue, one row of endothecium, two to four rows of middle layer and one row of tapetum layer. In the anther walls, the tapetal cells, by glandular type, persist later in ontogenesis. Pollen grains are tricolpate with echinate surface. The gynoecium is multiple, apocarpous with distinct carpels. The carpels are ascidiate from the beginning. At the base of each carpel, numerousness short, unicellular, trichomes are present. The stigma differentiates as two crests along the ventral slit of the ovary. Each carpel contains a single ovule inside the ovary cavity. The mature ovule is anatropous, with two integuments. It is almost parallel to the funicle

LEAF MICROMORPHOLOGY IN BUXUS SEMPERVIRENS L. DURING THE ONTOGENESIS

Abstract. Ultrastructural aspects of leaf epicuticular waxes were investigated in Buxus sempervirens by scanning electron microscopy. The leaves were hypostomatic and stomata were surrounded with a cuticular thickening that formed a rim. The most prominent epicuticular wax structures of B. sempervirens leaves included granules and platelets

Pharmacognostical analysis and seasonal variation of triterpenic and phenolic compounds from birch (Betula pendula Roth.) leaves

Universitatea de Medicină şi Farmacie ,,Carol Davila”, Facultatea de Farmacie, Bucureşti, România, Universitatea Bucureşti, Facultatea de Biologie, România, Universitatea ,,A.I. Cuza”, Facultatea de Biologie, Iaşi, RomâniaObiective. Scopul studiului constă în analiza farmacognostică şi determinarea dinamicii de acumulare a compuşilor fenolici şi triterpenici din frunzele speciei Betula pendula Roth. (mesteacăn). Material şi metode. Ca material s-au utilizat frunze de mesteacăn recoltate în anul 2011, din localitatea Morăreşti, judeţul Argeş, în diferite stadii de dezvoltare – lunile mai, iunie, iulie şi sfârşitul lunii august. Metodele utilizate au fost: analiza farmacognostică – examen macroscopic (la stereomicroscop), microscopic (pe secţiuni transversale, pulberi clarificate cu chloralhidrat şi prin microscopie electronică), chimic calitativ, cromatografie în strat subţire (CSS) şi determinarea spectrofotometrică (pe baza unor curbe etalon) a conţinutului de derivaţi fenolici (flavone – g% hiperozidă, acizi fenolcarboxilici – g% acid clorogenic, taninuri – g% pirogalol, proantociani – g% clorură de cianidol) şi triterpenici (forme libere, heterozidate şi esterificate – g% acid betulinic). Rezultate. Caracteristicile macroscopice ale produselor vegetale din toate loturile au coincis cu datele din literatura de specialitate consultată. Examenul microscopic efectuat pe secţiuni transversale şi pe pulberi clarificate a evidenţiat prezenţa de elemente specifice produsului vegetal de tip folium (fragmente de epidermă, stomate de tip anomocitic, peri tectori şi glandulari, teşut palisadic, clorofilian şi lacunar). Prin microscopie electronică s-au observat particularităţile formaţiunilor secretoare (glande peltate), dependent de gradul de dezvoltare al frunzelor (în frunzele tinere celulele secretoare sunt complet acoperite de cuticulă, iar spre sfârşitul perioadei de vegetaţie acestea degenerează). Prin analiza CSS s-au identificat următorii constituenţi: hiperozidă, quercitrozidă, quercetol, kaempferol, miricetol, acid clorogenic, acid ursolic/oleanolic şi betulinol. Conţinutul de acizi triterpenici (forme libere, esterificate şi heterozidate) scade odată cu maturizarea frunzelor (de la 11,7818 g%; 10,9276 g%; 4,3568 g% în luna mai la 4,9641 g%; 4,3038 g%; 2,1586 ± g% în luna august). Frunzele tinere (recoltate în luna mai) au cel mai mare conţinut de flavone (5,1885 g%), acizi fenolcarboxilici (3,4667g%) şi taninuri (3,2100 g%). Cantitatea de proantociani creşte odată cu maturizarea frunzelor, probabil datorită condensării cu taninurile. Concluzii. Frunzele de mesteacăn recoltate la începutul perioadei de vegetaţie (luna mai) au un conţinut ridicat de flavone, taninuri, acizi fenolcarboxilici şi derivaţi triterpenici. Scăderea conţinutului de principii active odată cu maturizarea produsului vegetal se corelează cu observaţiile microscopice asupra formaţiunilor secretoare, dependent de gradul de dezvoltare al frunzelor

MORPHOLOGICAL AND MICROMORPHOLOGICAL INVESTIGATIONS REGARDING THE LEAVES OF SEVERAL ROSA L. SPECIES

Multicellular secretory glands are present on Rosa L. species, at least on the stipellae edge; some of them have a larger number and different particularities. The researches have been made on leaves of the following species: Rosa agrestis, R. x damascena, R. multibracteata, R. pimpinellifolia and R. rubiginosa. Micromorphological studies emphasized a large number of cells which forming both terminal secretory part and foot, even though their dimensions are small. These researches highlight the micromorphological aspect of these glands, tector hairs and epicuticular wax. All of them were examined through scanning electron microscopy method

A New Species of <i>Megastigmus</i> and First Record of the Genus and Megastigmidae Family from the Paradise of the Maldives Archipelago

Megastigmidae comprises more than 200 species in 12 genera. Megastigmus has a worldwide distribution with more than 150 species. Over 80% of these species are recorded from the Australian and Palearctic region, with a few from Afrotropical and Oriental regions, but none from the Neotropical region. We describe a new species of Megastigmus obtained from the seeds of Pemphis acidula in the Maldives Archipelago. This is the first mention of Megastigmidae having as a host plant a species from Lythraceae. It is also the first recorded association of Chalcidoidea with the genus Pemphis and the first mention of Megastigmidae and Megastigmus in the Maldives Archipelago. We provide a detailed description of the species, focusing on its morphology, using both light microscopy and scanning electron microscopy (SEM). Megastigmus irinae Popescu n. sp. is a strictly phytophagous species, with each larva consuming a single seed. Currently, M. irinae is an endemic species found only in the Maldives Archipelago. However, considering the distribution of its host plant, P. acidula, which ranges from East Africa to Southeast Asia, Australia, Micronesia, and French Polynesia, we anticipate that future research could significantly expand the known range of this interesting new species

Lipopeptides produced by Bacillus subtilis as new biocontrol products against fusariosis in ornamental plants

National audienceIn this study, we have investigated the effects of three lipopeptides (fengycin, surfactin and mycosubtilin) produced by different strains of Bacillus subtilis against the phytopathogenic fungi Fusarium oxysporum f. sp. iridacearum, which affects the ornamental bulb plant populations of Iris sp. The antifungal effects were tested using minimum inhibitory concentration assay, determination of mycelium growth and spore germination inhibition rates. Also, in vivo tests on infected rhizomes and scanning electron microscopy were employed. Mycosubtilin alone and in combination with fengycin or/and surfactin showed potent inhibitory activity at concentrations as low as 5gml(-1) which is 100 times lower compared to Topsin M, a common chemical fungicide frequently used against fusariosis in ornamental plants. An enhancement of mycosubtilin antifungal activity was observed when it was used in combination with surfactin due to a synergistic effect. At a concentration of 20gml(-1), mycosubtilin inhibited the growth of the mycelium up to 49% and the spore germination ability up to 26% in comparison to control. In addition, significant changes on the macro- and micro-morphology have been observed. The antifungal activity is related to the inhibition of spore germination and the irreversible damage of the hyphae cell wall. To the best of our knowledge, this is the first attempt to propose the lipopeptides as biopesticides against the fusariosis of ornamental plants