Search results for "plant ecology"

Chromosome numbers and DNA ploidy levels of selected species ofHieracium s.str. (Asteraceae)

2007

Chromosome numbers and /or ploidy levels are reported for 44 species and subspecies ofHieracium s.str. from the following European countries: Andorra, Austria, Bulgaria, Czech Republic, France, Italy, Montenegro, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland and Ukraine. The chromosome numbers/DNA ploidy levels ofH. bocconei (2n ∼ 4x),H. bupleuroides subsp.leviceps (2n = 27),H. caesioides subsp.caesioides (2n = 27),H. basifolium (H. caesium agg., 2n = 36),H. plumbeum (H. caesium agg., 2n = 36),H. glaucum subsp.nipholepium (2n= 27),H.gouanii (2n = 18),H. gymnocerinthe (2n = 27),H. ramondii (2n = 27),H. recoderi (2n = 18),H. stelligerum (2n = 18), andH. tomentosum (2n = 18, 2n ∼ 2x, …

Capparis kebarensis, a new species of Capparaceae from Papua Barat, Indonesia

2012

The new species Capparis kebarensis Fici (Capparaceae) is here described and illustrated. Its affinities are discussed.

Macroecology meets global change research

2007

Interaction of a host plant and its holoparasite: effects of previous selection by the parasite

2001

If parasites decrease the fitness of their hosts one could expect selection for host traits (e.g. resistance and tolerance) that decrease the negative effects of parasitic infection. To study selection caused by parasitism, we used a novel study system: we grew host plants (Urtica dioica) that originated from previously parasitized and unparasitized natural populations (four of each) with or without a holoparasitic plant (Cuscuta europaea). Infectivity of the parasite (i.e. qualitative resistance of the host) did not differ between the two host types. Parasites grown with hosts from parasitized populations had lower performance than parasites grown with hosts from unparasitized populations,…

Wuchsform und Organisation vonMonsonia nivea (Geraniaceae) unter besonderer Ber�cksichtigung der Blattstieldornen

1979

Monsonia nivea is a hemicryptophyte which shows spiny petioles after the loss of leaf blades. Anthocladial inflorescences and their supporting vegetative parts are spineless. Spines are formed only by vigorous rosettes. Similar spiny petioles can be found in all other genera of the tribeGeranieae.

A new species ofFumana (Cistaceae) from Rif, Morocco

1999

A new species ofFumana (Dunal) Spach subgenusFumana, F. fontqueri, is described from the region of Rif, Morocco. Notes on its morphology, ecology, distribution and taxonomic relationships are presented. It differs fromF. procumbens (Dunal) Gren. etGodr. andF. baetica Guemes, by the indument of the stem, the disposition of pedicels, and the size of the flowers.

SEM-Untersuchungen an myxospermen Diasporen

1980

The epidermal structure of mucilage producing seeds and fruits before and after contact with water is studied. Main emphasis is laid on the elucidation of structural peculiarities of the dessicated mucilaginous substances.

Nectar sugar production across floral phases in the Gynodioecious Protandrous Plant Geranium sylvaticum [corrected].

2013

Many zoophilous plants attract their pollinators by offering nectar as a reward. In gynodioecious plants (i.e. populations are composed of female and hermaphrodite individuals) nectar production has been repeatedly reported to be larger in hermaphrodite compared to female flowers even though nectar production across the different floral phases in dichogamous plants (i.e. plants with time separation of pollen dispersal and stigma receptivity) has rarely been examined. In this study, sugar production in nectar standing crop and secretion rate were investigated in Geranium sylvaticum, a gynodioecious plant species with protandry (i.e. with hermaphrodite flowers releasing their pollen before th…

Limnogēno purvu veģetācija Latvijā

2006

Advisor: Pakalne, Māra

Influence of arbuscular mycorrhizae on biomass production and nitrogen fixation of berseem clover plants subjected to water stress.

2014

Several studies, performed mainly in pots, have shown that arbuscular mycorrhizal symbiosis can mitigate the negative effects of water stress on plant growth. No information is available about the effects of arbuscular mycorrhizal symbiosis on berseem clover growth and nitrogen (N) fixation under conditions of water shortage. A field experiment was conducted in a hilly area of inner Sicily, Italy, to determine whether symbiosis with AM fungi can mitigate the detrimental effects of drought stress (which in the Mediterranean often occurs during the late period of the growing season) on forage yield and symbiotic N2 fixation of berseem clover. Soil was either left under water stress (i.e., rai…