BACKGROUND AND AIMS In some dicotyledonous leaves and leaflets, the secondary veins run more-or-less straight to the margins and have well-defined lengths. For a given half-lamina of length L, an equation, previously proposed, relates the lengths of these veins, p, to the distances, l, between the leaf tip and their insertions on the midrib: p = B2(x+y)l(x)(L - l)(y)/L(x+y-1), where B, x and y ...

In 2016–2021 the ravines floristic diversity of Khinna gorge (Zayamchay river basin, Lesser Caucasus) was studied. is located on right bank Zayamchay river, at foot Gizilja Mount. gorge, 18 species, 13 genera and 11 families plants were found. Plants relict origin also found: Poa nemoralis L., compressa Ulmus glabra Huds., Parietaria chersonensis (Lang & Szov.) Dörfl., Asparagus verticillat...

In a multiple-choice test, the preference of egg-laying Polygonia c-album (comma butterfly) females was studied for oviposition on plants bearing surrogate leaves treated with crude methanol extracts obtained from leaves of seven host-plant species: Humulus lupulus, Urtica dioica, Ulmus glabra, Salix caprea, Ribes nigrum, Corylus avellana, and Betula pubescens. The ranking order of surrogate le...

dutch elm disease is one of the most destructive and common plant vascular diseases now which isknown as a global problem. the aim of this study was comparison of early- and late-wood vesselsdiameter and ray dimensions. in 4 species: ulmus carpinifolia, zelkova carpinifolia, ulmus glabra andceltis australis from ulmaceae. then, very thin transversal sections were prepared and after differentsta...

The aphid genus Tinocallis Matsumura, 1919 (Hemiptera: Aphididae: Calaphidinae) in central and northern Europe is reviewed; it includes four species. The first records of the Asian elm aphid Tinocallis takachihoensis Higuchi, 1972 are reported from the Czech Republic, Denmark, and Poland. The record in Denmark is the first in Scandinavia. Alate viviparous females and nymphs of T. takachihoensis...

Radial increment objectively reflects the quality of assimilation apparatus a woody plant. Its features indicate influence various anthropogenic, biotic and abiotic factors as well stability plant under stress. The aim this study was to survey long-term dynamics radial growth six tree species: Betula pendula, Ulmus glabra, Quercus robur, Tilia cordata, Picea abies Pinus silvestris, depending on...