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Agrostis palustris sods were grown sequentially in a controlled environment chamber at 20–10, 25–15, 30–20, 35–25, and 40–30°C day‐night temperature regimes. Leaves grown at 40–30°C contained 53% more ethanol soluble and 51% more water soluble carbohydrate than those grown at the 4 lower temperature regimes. The increase in ethanol and water soluble carbohydrate in leaves at 40–30°C could not be attributed to a blockage in translocation of photoassimilate to lower plants parts based on quantitative carbohydrate analyses on stem and stolon tissue. Manometric measurements of photosynthesis indicated that leaf blades grown at the five temperature regimes exhibited different rate capabilities when tested under non‐limiting light and carbon dioxide levels. Oxygen evolution increased directly with temperature from 20 to 40°C and was 8 to 11 fold greater than the rate of carbon dioxide evolution. Both quantitative and qualitative differences in the photosynthetic rate were postulated in the leaf blade tissue tested. The quantitative difference was attributed to a possible difference in the number of cells per unit area and their size. The qualitative difference was attributed to greater thermal stability of leaf proteins when plants were grown at supraoptimal temperatures. Manometric respiratory rate studies did not indicate similar differences in temperature response in leaf blade tissue grown at the five temperature regimes. The cause of decreased shoot growth at supraoptimal temperatures could not be attributed to decreased and limiting C‐6 carbohydrate synthesis. [ABSTRACT FROM AUTHOR]

Agrostis palustris turfs cut weekly at 1.3 cm were subjected to successive four‐week periods with day‐night temperature regimes of 20–10, 25–15, 30–20, 35–25 and 40–30°C. Plants grown at 40–30°C exhibited a growth character distinctly different from those grown at 20–10°C. They were more upright and bristle‐like in growth habit. The percentage dry weight of leaf blade tissue increased 67% and weight per unit area increased 53% between 20–10 and 40–30°C. Reduced leaf blade width was noted first at 30–20°C while leaf blade length reduction first occurred at 35–25°C. Weekly yields were significantly reduced at the supraoptimal temperature regimes of 35–25 and 40–30°C. Chlorophyll content was lowest at 20–10 and 40–30°C, the lowest and highest temperature regimes studied. Shoot density appeared to decrease under the 35–25°C regime, but no dead plants were observed. The apparent decrease in shoot density was attributed to the upright growth habit. Density decreased at 40–30°C upon death of individual plants. A community of grass plants maintained as a turf was found to change in form quite rapidly in response to temperature. [ABSTRACT FROM AUTHOR]

Zinc and copper uptake by Agrostis stolonifera, tolerant to both zinc and copper, showed that different zinc levels had no effect on copper uptake and, conversely, copper had no effect on zinc uptake. There was, however, a strong interaction in the toxic effects of zinc and copper as measured by root elongation. The mechanisms of zinc and copper tolerance are therefore independent even when they act in the same individual. [ABSTRACT FROM AUTHOR]

The uptake of copper by non-tolerant and tolerant clones of Agrostis stolonifera has been studied. In both clones the roots accumulated more copper than the leaves and the roots of the tolerant clone accumulated more copper than the non-tolerant one. When supplied at concentrations above 10 μM in culture solutions copper moved up into the leaves of the non-tolerant clone more readily than the tolerant one. Uptake of oxygen by roots was only affected when they were pretreated with copper, the non-tolerant ones being more sensitive to inhibition than tolerant ones. Over the concentration range tested copper had no effect upon l-malate-dehydrogenase (MDH) activity in root extracts of either clone. Extracts prepared from non-tolerant roots pretreated with copper were found to contain less MDH activity than those prepared from tolerant ones. It is suggested that this was due to an inhibition of protein synthesis in the roots of the non-tolerant clone, which did not occur in the tolerant one. [ABSTRACT FROM AUTHOR]

The influence of temperature was studied in relation to nitrate reductase activity of creeping bentgrass (Agrostis palustris Huds. cv. 'Toronto') a cool season grass and bermudagrass (Cynodon dactylon L. cv. 'Tifgreen') a warm season grass. Maximum nitrate reductase activity of both species occurred at 20°C. The nitrate reductase level in bentgrass leaves was reduced when grown at 35°C while bermudagrass leaves were relatively unaffected. The activity per se of the bentgrass enzyme preparation was inhibited rather than synthesis of the enzyme. [ABSTRACT FROM AUTHOR]

Epichloe typhina forms an intercellular systemic mycelium within its host, Agrostis stolonifera, and a stroma (upon which conidia and perithecia are produced) at the junction of the lamina and sheath of the flag leaf where association between the stroma and vascular tissue of the host is close. There is movement of labelled photosynthate to the stroma from other parts of the shoot. Movement through the systemic mycelium appears to be slight and most probably occurs through the host vascular tissue with subsequent uptake of photosynthate by the stroma. The principal carbohydrate acquired from the host is sucrose, and there is concomitant transformation to mannitol and trehalose by the fungus. [ABSTRACT FROM AUTHOR]

The article presents a study on the influence of iron and manganese and waterlogging on the growth and distribution of Agrostis stolonifera, Festuca rubra, Carex flacca and Carex nigra. Results showed that in terms of the plants' appearance, there were no visible differences between A. stolonifera and C. flacca in various treatments applied. However, small dark brown spots were observed on some leaves of F. rubra in the manganese treatment. The shoot manganese content of all species, except C. nigra, increased with increasing manganese content of the culture solutions. Also, growth of the Carices was enhanced by increasing the concentration of manganese.

The article presents a study on the influence of the relationship among iron and manganese and waterlogging on the growth and distribution of Agrostis stolonifera, Festuca rubra, Carex flacca and Carex nigra. It states since C. flacca is the only one of the four plants to occur in dune, slack and intermediate habitats were also collected and examined to identify whether the experimental tretments were actually simulating the natural environment in this respect. Results showed that the plants in dune sand behaved differently than those in slack sand. In all cases, the increasing wetness from the dune to the slack sites was associated with a marked increase in the iron and manganese content of shoot and root tissues.

The article presents a study on the effects of phosphorus content in soil on the growth of the plant Agrostis setacea. It mentions that studies on the differences of adaptive behaviors in plants to the shortage of nutrients in soil are hard to quantify. The study argues that in the study of Agrostis, the supply of phosphorus in soil must be low to compare growth and survival rates. An experiment was carried out using soil samples from Haldon Ridge, Devon which were examined for nutrient content. Plants were grown on culture solutions. An overview of the study is provided.

The article compares the calcium uptake and the growth responses of Agrostis canina, Agrostis setacea, Agrostis stolonifera and Agrostis tenuis to various calcium concentrations. Information on the soil and water cultures used in the experiments is presented. A detailed description of the preparation of material for analysis is presented. The soils used in the study were collected from plots on the Haldon Ridge, Devon, on which field trials had been carried out earlier. The sources of seeds used in the study are presented.

The article presents a study on six grass species, including Lolium perenne, Cynosurus cristatus, Agrostis stolonifera, A. tenuis, A. canina and Nardus stricta, and their respective responses to varying calcium levels in sand culture. It states that the six species were harvested after the treatments at three separate times. Results showed that Lolium perenne, Agrostis stolonifera and Cynosorus cristatus increased their growth with an increase in calcium at lower levels, while A. tenuis and A. canina increased their growth at all levels. Nardus stricta, however, increased its growth in calcium, but was depressed at higher levels.

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The article compares plant growth and distribution in relation to waterlogging, which means simulated slack moisture regime, with focus on the growth of dune and dune slack plants in Glamorganshire, Wales. The article also investigates the effect of different water regimes on the growth of Agrostis stolonifera, Festuca rubra, Carex flacca and Carex nigra in pots of sand in a glasshouse. The study found that waterlogging caused a considerable reduction of soil compared with the freely draining control treatment and also caused reduction of tiller production by the grasses.