Extensive past efforts have been taken toward understanding heat tolerance mechanisms of the aboveground organs. Root systems play critical roles in whole-plant adaptation to heat stress, but are less studied. This review discusses recent research results revealing some critical physiological and metabolic factors underlying root thermotolerance, with a focus on temperate perennial grass specie...

This thesis is based on the following articles and manuscripts, which are referred to in the text by their Roman numerals: Mesocosms mimic natural meadows as regards greenhouse gas fluxes and potential activities of nitrifying and denitrifying bacteria. Plant and Soil 276: 287-299. soil microbial community structure under elevated tropospheric O 3 and CO 2. Submitted for publication. Difference...

Lineage-specific gene loss is considered one of the processes contributing to speciation and genome diversity. Such gene loss has been inferred from interspecies comparisons of orthologous DNA segments. Examples of intraspecific gene loss are rare. Here we report identification of a gene, designated Crs-1 (creeping specific-1), that appears to be in the process of being lost from heterozygous p...

The planting of 162 ha of transgenic glyphosate-resistant creeping bentgrass (Agrostis stolonifera) near Madras, OR, USA, allowed a unique opportunity to study gene flow over time from a perennial outcrossing species at the landscape level. While conducting a four year in situ survey, we collected panicles and leaf tissue samples from creeping bentgrass and its sexually compatible species. Seed...

Protein metabolism plays an important role in plant adaptation to heat stress. This study was designed to identify heat-responsive proteins in roots associated with thermotolerance for two C3 grass species contrasting in heat tolerance, thermal Agrostis scabra and heat-sensitive Agrostis stolonifera L. Plants were exposed to 20 degrees C (control), 30 C (moderate heat stress), or 40 degrees C (...

Creeping bentgrass (Agrostis stolonifera, allotetraploid 2n = 4x = 28) is one of the major cool-season turfgrasses. It is widely used on golf courses due to its tolerance to low mowing and aggressive growth habit. In this study, we investigated genome relationships of creeping bentgrass relative to the Triticeae (a consensus map of Triticum aestivum, T. tauschii, Hordeum vulgare, and H. spontan...

A molecular analysis of eight described species of seed gall nematode, along with six undescribed isolates from different hosts, has revealed a strong association between nucleotide sequence polymorphism and host status. Each anguinid nematode associated with a unique host produced a unique PCR-RFLP pattern for the ITS1 region. Anguina species that had been synonymized in the past, Anguina agro...