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Bikash Baral, Geeta Shrestha Vaidya, Bijaya Laxmi Maharjan and Jaime A. Teixeira Da Silva

: Journal of Plant Sciences, 8: 33-39. Bhattacharyya D., 2011: Rhododendron species and their uses with special reference to Himalayas - a review. - Assam university Journal of Science and Technology, 7: 161-167. Chao Y., Xiu J.Z., Yuan D.D., Yu H.G., Li Y.S., Qiang R., Zun T.Z., 2010: Antimicrobial compounds and other constituents of Evernia divaricata (L.) Ach. - Journal of the Chemical Society of Pakistan, 32(2): 189-193. Chhetri H.P., Yogol N.S., Sherchan J., Chhetri A.K., Mansoor S., Thapa P., 2008: Phytochemical and antimicrobial evaluations of some

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Boštjan Surina and Marash Rakaj

Subalpine Beech Forest with Hairy Alpenrose (Polysticho Lonchitis-Fagetum Rhododendretosum Hirsuti Subass. Nova) on Mt. Snežnik (Liburnian Karst, Dinaric Mts)

Subalpine beech stands with Hairy Alpenrose (Rhododendron hirsutum) were phytosociologically studied on Mt. Snežnik (Dinaric Mts). They thrived on stony and steep slopes of northern exposure. Comparisons with other subalpine Beech stands (Polysticho lonchitis-Fagetum s. lat.), Dinaric Fir-Beech stands with Hairy Alpen-rose (Omphalodo-Fagetum s. lat. rhododendretosum hirsuti), and prealpine fir-beech stands with Hairy Alpenrose (Homogyno sylvestris-Fagetum s. lat. rhododendretosum hirsuti), stands of Hairy Alpenrose and Beech (Rhododendro hirsuti-Fagetum s. lat.), as well as Austrian subalpine beech stands (Saxifrago rotundifoliae-Fagetum s. lat.) showed their unique floristical composition due to ecological conditions, and thus distinct syntaxonomical position within the association Polysticho-Fagetum. Therefore, a new subassociation Polysticho-Fagetum rhododendretosum hirsuti subass. nova was described, and - as differential species for the subassociation - Rhododendron hirsutum, Rubus saxatilis, Rosa pendulina, and Clematis alpina were chosen.

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Marek Barta and Tomáš Bibeň

. Klapalekiana 44: 165-206. Johnson W.T., Lyon H.H. 1991. Lace bugs of broad-leaved evergreens and sages. p. 424‒429. In: “Insects that Feed on Trees and Shrubs”. 2nd ed. (W.T. Johnson, H.H. Lyon, eds.), Ithaca, Comstock Publishing Associates, 560 pp. Jones R.A. 1993. The rhododendron lace bug, Stephanitis rhododendri Horvath, rediscovered in south-east London. British Journal of Entomology and Natural History 6: 139‒140. MacLeod A. 2000. Stephanitis takeyai Pest Risk Analysis for PHSC. Central Science Laboratory, York, UK, 5 pp

Open access

Boštjan Surina

Abstract

The ecology and phytosociology of north-western Dinaric heaths of the association Rhododendro hirsuti-Juniperetum alpinae Horvat ex Horvat et al. 1974 nom. corr. prop. as well as the syndynamics and synsystematics of heaths in the Dinaric Alps are discussed. While the structure (physiognomy) of these stands is very homogenous and dominated by few species, the flora is heterogeneous, since ecotonal areas, where heaths are most frequently developed, represent a contact zone of elements of different syntaxa. Due to an abrupt reduction in pasture activities strong encroachments of shrubs and trees have become common, which additionally contribute to the floristic heterogeneity of the heaths. Although the identification and circumscription together with synecology and synchorology of heaths in general are more or less easily understood and straightforward, their floristic affinities, in relation to structure homogeneity and syndynamics, are complicated, which led to the proposal of several synsystematic schemes depending on interpretation of the relationship between flora and structure of stands. Dinaric heaths are classified into three classes, Erico-Pinetea, Vaccinio-Piceetea and Festuco-Brometea and a classification scheme is proposed together with nomenclatorial revision of the analyzed heaths with dwarf ericaceous shrubs and Alpine juniper (Juniperus alpina) in the Dinaric Alps

Open access

Igor Dakskobler and Boštjan Surina

Abstract

By means of a phytosociological analysis of 72 relevés of montane-subalpine shrub communities with dominating Rhododendron hirsutum, Salix waldsteiniana, S. glabra and S. appendiculata from the Julian Alps and the the Trnovski Gozd Plateau and by comparing them with similar communities elsewhere in the Alps and the Dinaric Alps we described a new association Laserpitio peucedanoidis-Salicetum waldsteinianae, a new subassociation Rhododendretum hirsuti vaccinietosum myrtilli, two new subassociations of the association Dryado-Rhodothamnetum chamaecisti that had recently been described in the Dolomites (-caricetosum firmae, -salicetosum waldsteinianae), as well as a new association Heliospermo pusillae-Rhododendretum hirsuti. We classified the glabrous willow community in the study area into a new association Homogyno sylvestris- Salicetum glabrae and proposed a new name - Rhododendro hirsuti-Salicetum appendiculatae for the large-leaved willow community, which we subdivided into two geographical variants: var. geogr. Paederota lutea (Julian Alps, Trnovski Gozd Plateau) and var. geogr. Hypericum grisebachii (Liburnian Karst).

Open access

Leszek Orlikowski and Magdalena Ptaszek

First Notice of Phytophthora Stem Base Rot on Syringa Vulgaris in a Polish Field Nursery

Phytophthora citrophthora was isolated from grafted lilac (Syringa vulgaris). Showing browning of leaf blade edge and necrosis spreading on all leaves. On the stem bases, beginning from the grafted place, necrosis had even spread 20 cm upward, whereas root stock shoots and roots were healthy. Using rhododendron leaves as the bait, Phytophthora citrophthora was isolated from soil where growing plants showed stem base rot symptoms. Isolates of Phytophthora which were from the stem base, shoot tip of lilac, and soil, colonized leaves, stem parts and roots of lilac. Necroses spread about twice faster on leaf blades than on stem parts. Three isolates of Phytophthora colonized also Forsythia intermedia and Ligustrum vulgare.

Open access

Aneta Sikora, Paweł Michołap and Maria Kelm

Abstract

Due to fewer bumblebees in rural areas these days, it is necessary to look for alternative habitats for the active protection of these very important pollinators. The research was carried out in The Botanical Garden of Medicinal Plants, in Wrocław, Poland. In the garden, approximately 2000 plant species were cultivated, of which 185 were visited by bumblebees. Amongst them, 57 plant species were deemed very attractive and were determined to be indicators for 7 bumblebee species. Indicator species for bumblebees ranged between 6 for Bombus pratorum to up to 20 for B. pascuorum. Monarda didyma was an indicator plant to 6 recorded bumblebee species. Other indicator plant species for at least 4 bumblebees species were: Origanum vulgare, Lavandula angustifolia, Rhododendron catawbiense, Phacelia tanacetifolia, and Agastache rugosa. Three bumblebee species were found to forage the most on 11 of the flowering plant species. The biggest group of plants were those which were mostly visited by 1-2 bumblebee species. Amongst all recorded indicator plants, 32% were native species.

Open access

Leszek Orlikowski, Magdalena Pļaszek, Adam Wojdyļa and Czesļaw Skrzypczak

First Notice of Phytophthora Aerial Blight and Crown Rot on Pansies in Poland

Phytophthora cactorum was detected on &9/10; of pansies showing yellowing of leaves and crown rot symptoms and constituted about 90% of isolates obtained. Botrytis cinerea, Fusarium avenaceum, F. solani and Pythium ultimum were also isolated from diseased tissues. Using rhododendron leaves as the bait, P. cactorum was detected in pansy substratum as well as from soil under the mata. Isolates obtained from diseased plants, substratum and soil under mata colonized leaves, stem parts and roots of pansy. Necroses spread faster on organs inoculated with cultures from plants and substratum. Among 25 cultivars inoculated with P. cactorum, disease symptoms did not occur on 3 of them, whereas the fastest spread of necrotic spots (3.8 mm/24 hrs) was noticed on 3 cultivars. Isolates of P. cactorum from Begonia semperflorens and Malus domestica colonized leaf petioles of pansy with significantly faster spread when isolates from begonia and pansy were used for inoculation.

Open access

Subodh Airi and Ranbeer S. Rawal

Abstract

This study analyses the impacts of canopy disturbance on vegetation compositional attributes of two characteristic temperate forests (i.e., mixed broad-leaf and banj-oak forests) in west Himalayan part of India. Following the standard approaches, quantitative information on compositional attributes of forest vegetation was generated and analyzed. Considerable changes in these attributes were revealed across different levels of canopy disturbance in both forests. In particular, tree density and total basal area (TBA) exhibited significant decline from undegraded to degraded stands. Among others, seedling and sapling density of mixed broad-leaf forest was affected adversely by increased level of canopy disturbance. However, herb density in this forest increased significantly with increasing levels of disturbance; the same was not true for banj-oak forest. A significant decline in relative frequency and density of native herbaceous species was apparent towards degraded stands, implying that the disturbed sites in both forests created an opportunity for the establishment and proliferation of non-natives. However, with significant increase in relative density of non-native herbs, the degraded stands of banj-oak forest emerged as critically vulnerable to non-native proliferation. The patterns of tree size class distribution in both forests also exhibited certain trends across canopy disturbance, which suggested possible future changes in composition. In particular, the patterns of common tree associates (i.e., Myrica esculenta and Rhododendron arboreum) in banj-oak forest and Pinus roxburghii in mixed broad-leaf forest were indicative of likely compositional changes in near future. The study concludes that: (i) compositional attributes of both mixed broad-leaf and banj-oak forests were sensitive to increasing levels of canopy disturbance, (ii) mixed broad-leaf forest exhibited greater sensitivity to canopy disturbance at recruitment levels, (iii) increased canopy disturbance led to establishment and proliferation of non-native species in the herbaceous layer of both forests, and (iv) banj-oak forest exhibited high vulnerability to non-native proliferation at degraded stage.