Action spectra were measured for suppression of germination of Poa pratensis L. and Amaranthus arenicola I. M. Johnston seed under prolonged or continuous irradiation. The action maxima for both types of seeds are near 720 nm. The maxima are unchanged in position or magnitude in the presence of radiation in the region of 600 to 670 nm adequate to maintain phytochrome predominantly in the far-re...

Punctodera punctata completed its life cycle on Poa annua (annual bluegrass), P. pratensis (Merion Kentucky bluegrass), Lolium perenne (perennial ryegrass), and Festuca rubra rubra (spreading fescue). Minimum time for completion of a life cycle from second-stage juvenile to mature brown cyst was 40 days at 22-28 C. Inoculation by single juveniles indicated that reproduction was most likely by a...

Pratylenchus arlingtoni n. sp. from the rhizosphere of grasses Poa pratensis and Festuca arundinacea at Arlington National Cemetery, VA, USA is characterised by six to eight lines in the lateral Ž eld, and pyriform to slightly overlapping pharyngeal glands.Morphological comparisons are made with lesion nematodes having similar morphometrics, six lateral lines, or crenate tail tips. Molecular se...

Strain F31T was isolated from meadow grass (Poa trivialis L.) sampled from the city park in Helsinki. Analysis of phenotypic and genotypic properties showed the strain to be related to the group of obligately methylotrophic non-methane utilizing bacteria (methylobacteria) with the ribulose monophosphate pathway of formaldehyde assimilation. Phylogenetic analysis showed the strain to be closely ...

List of papers This thesis is based on the following papers, which will be referred to in the text by their Roman numerals. Effects of intensified management of hay-meadows on population dynamics of Succisa pratensis. Manuscript. Intensified management affects population growth differently in the two perennial herbs Hypochoeris maculata and Polygala amarella. Manuscript. Artificial dispersal as...