abstract in order to evaluate chemical control of bermudagrass (cynodon dactylon (l.) pers.) on mixture turf: (lolium perenne 20%,poa pratensis.20%,festuca arundinacea 20% and festuca rubra commutata 40%), an experiment was conducted during 2006 in tehran, using randomized complete block design with 4 replications and 11 treatments. treatments were diclpfop methyl at 900 and 1080 g a.i. ha-1, f...

The extent of root, rhizome, and/or stolon growth determines turfgrass sod maturity. In 1998, at Michigan State University, the Calrochan Sod Puller (CSP) was developed to measure the force necessary to tear a piece of sod. The CSP uses a battery powered hydraulic pulley to provide a consistent pulling force, and is attached to a load cell. In August 1999, sod strength measurements of different...

The effect of Tylenchorhynchus nudus on growth of Kentucky bluegrass was investigated under controlled environmental conditions in both a phytotron and a greenhouse. The nematode significantly reduced weights of clippings, crowns and roots. Pathogenicity was greater in sandy loam soil than in loam and was enhanced by submitting plants to nutrient and/or moisture stresses; soil nutrient level wa...

Elevated CO2 concentration may promote plant growth while high temperature is inhibitory for C3 plant species. The interactive effects of elevated CO2 and high temperatures on C3 perennial grass growth and carbon metabolism are not well documented. Kentucky bluegrass (Poa pratensis) plants were exposed to two CO2 levels (400 and 800 μmol mol-1) and five temperatures (15/12, 20/17, 25/22, 30/27,...

Insects in Kentucky bluegrass seed production fields in Oregon, Idaho, and Washington were sampled just before harvest and their association with ergot conidia of Claviceps purpurea Fr. (Tul.) was evaluated during 1996-1998. A diversity of insects was observed at all three locations. The most abundant beneficial insects collected with sweep nets were Nysium spp., Nabis spp., ichneumonid wasps, ...

Nitrous oxide (NO) emissions are an important component of the greenhouse gas budget for turfgrasses. To estimate NO emissions and global warming potential, the DAYCENT ecosystem model was parameterized and applied to turfgrass ecosystems. The annual cumulative NO emissions predicted by the DAYCENT model were close to the measured emission rates of Kentucky bluegrass ( L.) sites in Colorado (wi...

Drought stress encumbers the growth of turfgrass principally by disrupting the plant-water relations and physiological functions. The present study was carried out to appraise the role of silicon (Si) in improving the drought tolerance in Kentucky bluegrass (Poa pratensis L.). Drought stress and four levels (0, 200, 400, and 800 mg L(-1)) of Si (Na2SiO3·9H2O) were imposed after 2 months old pla...

In grasses, food reserves in crowns and rhizomes support herbage production and allow regrowth in the spring. One important factor leading to the relative competitiveness of Kentucky bluegrass and smooth brome is that they initiate spring regrowth earlier than their native counterparts in the mixed-grass prairie. It still remains to be tested if there is a greater biomass investment to crowns o...

Phytoremediation efficiency mainly depends upon mechanisms in the uptake and translocation of soil contaminants. Cadmium (Cd) distribution and translocation in roots and shoots of tall fescue (Festuca arundinacea) and Kentucky bluegrass (Poa pratensis) were observed using fluorescence spectroscopy with a laser confocal scanning microscope. No difference in root Cd accumulations was detected bet...