Competitive ability

Rich T.J. and Hurst J.L. (1999). The competing countermarks hypothesis reliable assessment of competitive ability by potential mates. Anim Behav 58, 1027-1037. 

Parks and Rice (5 ) found that some soil algae are inhibited by rhizome extracts. This suggested that johnsongrass s competitive ability may be increased by it s ability to influence the soil microflora and thereby indirectly affect other higher plants. 

As stated earlier, mycorrhizae enhance nutrient absorption. Greater soil exploitation by mycorrhizal roots as a means of increasing phosphate uptake is well established. The normal phosphate depletion zone around non-mycorrhizal roots is 1-2 mm, but an endomycorrhizal root symbiont increased this zone to 7 cm (140). This ability to increase the nutritional level (particularly with regard to phosphorus), and subsequently the overall better growth dynamics of the mycorrhizal plant has been suggested as the reason for the salt (43) and drought (44-46) tolerance and increased nodulation (47) observed in mycorrhizal associations. Another interesting aspect of this enhanced nutrient uptake is the possible effect of mycorrhizae on competitive ability between two plant species. Under some conditions, mycorrhizal... 

Pryke, S. R. and Andersson, S. 2003a. Carotenoid-based epaulettes reveal male competitive ability Experiments with resident and floater red-shouldered widowbirds. Anim. Behav. 66 217-224. 

Rich, T.J. and Hurst, J.L. (1998) Scent marks as reliable signals of the competitive ability of mates. Anim. Behav. 56, 727-735. 

Fisher, H.S., Swaisgood, R.R. and Fitch-Snyder, H. (2003) Countermarking by pygmy lorises (Nycticebus pygmaeus) do females use odor cues to select mates with high competitive ability Behav. Ecol. Sociobiol. 53, 123-130. 

Lubchenco J (1978) Plant species diversity in a marine intertidal community importance of herbivore food preference and algal competitive abilities. Am Nat 112 23-39 Lumbang WA, Paul VJ (1996) Chemical defenses of the tropical green seaweed Neomeris annulata Dickie effects of multiple compounds on feeding by herbivores. J Exp Mar Biol Ecol 201 185-195... 

For farmers, controlling weeds in crops is absolutely essential. Lacy (1985) summarized weed control objectives as reducing the competitive ability of an existing population of weeds in a crop establishing a barrier to the development of further significant weeds within that crop and preventing weed problems in future crops either from an existing weed reservoir or from additions to the weed flora. 

This characteristic, however, is not universally found in all triazine-resistant weeds. Gray et al. (1995a, b) found that velvetleaf resistance to atrazine in Wisconsin was not associated with a reduction in fitness, productivity, or intraspecific competitive ability. This triazine-resistant species found in Maryland and Wisconsin does not have D1 level resistance in the chloroplasts, but instead has a more rapid metabolic detoxification of triazines in these biotypes. The extent of the rapid metabolic resistance in other velvetleaf-resistant biotypes is unknown. 

Gray, J.A., D.E. Stoltenberg, and N.E. Balke (1995b). Productivity and intraspecific competitive ability of a velvetleaf (Abutilon theophrasti) biotype resistant to atrazine. Weed Sci., 43 619-626. 

Munier-Jolain, N.M., B. Chauvel, and J. Gasquez (2002). Long-term modeling of weed control strategies Analysis of threshold-based options for weed species with contrasted competitive abilities. Weed Res., 42 107-122. 

Ditommaso, A., Watson, A.K. Impact of a fungal pathogen, Colletotrichum coccodes on growth and competitive ability of Abutilon theophrasti. New Phytol 1995 131 51-60. 

Friess, N., Maillet, J. Influence of cucumber mosaic virus infection on the competitive ability and reproduction of chickweed (Stellaria media). New Phytol 1997 135 667-674. 

Trorey, G.M. The effect of crown rust (Puccinia coronata lolii) on the yield and competitive ability of perennial ryegrass. PhD Thesis. Huddersfield, United Kingdom Huddersfield Polytechnic. 1979. 

One of the main obstacles for studying the allocation of resources is determining the appropriate currency to measure cost. The different currencies that have been used include (1) the energy stored in chemical bonds,69 (2) biomass allocated to various tissues or materials responsible for different biological functions,70 (3) the amount of limiting resource allocated to different processes, (4) the competitive ability of organisms with different allocation patterns, and (5) some measure of fitness trade-off.71... 

The competitive ability of shrub species, such as pink-bracted man-zanita or deerbrush, and other under story plants, such as grasses and bracken fern, must be considered especially on some of the more barren, dry sites. 

Sink strength is a measure of the sink s ability to accrue photosynthates, and the rate of change in dry weight of a particular sink is considered indicative of its competitive ability within the plant. 

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