Plants show phenological responses to herbivory. Some enclosure experiments have demonstrated that the onset of the peak flowering season is dependent on grazing pressure. We constructed a mathematical model using Pontryargin's maximum principle to investigate changes in flowering time by examining shifts in resource allocation from vegetative to reproductive plant components. We represented a ...

(1) Neighbourhood experiments were used to compare the magnitudes of competitive effect and competitive response using all pairwise combinations of Papaver rhoeas, Triticum aestivum and Avena sativa as neighbour species, and these three species plus Chenopodium album as target species. (2) Over 79% of the variance in target weight was explained by a simple hyperbolic function of neighbour weigh...

The effects of interand intraspecific interference on size hierarchies (size inequalities) were investigated in populations of the annual plants Trifolium incarnatum and Lollurn mult~florurn. Variables experimentally manipulated included plant density, species proportions, soil fertility. and spatial pattern of plantings. Densities were below those for extensive density-dependent mortality. Siz...

Masting is defined as the intermittent highly variable production of seed in a plant population. According to reproductive modes, that is, sexual and asexual reproduction, masting species can be separated into three groups, that is, (1) species, for example, bamboo, flower only once before they die; (2) species, for example, Fagus, reproduce sexually; and (3) species, for example, Stipa tenacis...

F-box proteins are generally responsible for substrate recognition in the Skp1-Cullin-F-box complexes that are involved in protein degradation via the ubiquitin-26S proteasome pathway. In plants, F-box genes influence a variety of biological processes, such as leaf senescence, branching, self-incompatibility, and responses to biotic and abiotic stresses. The number of F-box genes in Populus (Po...

Populations of the rare annual forb Amsinckia grandiflora may be declining because of competitive suppression by exotic annual grasses, and may perform better in a matrix of native perennial bunchgrasses. We conducted a field competition experiment in which Amsinckia seedlings were transplanted into forty 0.64-m 2 experimental plots of exotic annual grassland or restored perennial grassland. Th...

Ergonomic Work Analysis applied to Water Treatment Plants: integrating knowledge//and Handbook of Human Factors and Ergonomics, 4th Edition. Proceedings of the Human Factors and Ergonomics Society 42nd Annual In G. Salvendy (Ed.), Handbook of Human Factors and Ergonomics (4th Edition), pp. Proceedings of the Human Factors and Ergonomics Society Annual Meeting 10/2012, 56(1):2011-2015. DOI: 10.1...

BACKGROUND AND AIMS Adventitious sprouting from the hypocotyle and roots in monocarpic herbs has been confirmed in previous experimental studies as a means to avoid bud limitation after severe injury in annual and biennial plants. Data regarding the role of adventitious sprouting in natural populations, however, were lacking. The aim of the present study was to assess whether adventitious sprou...

We conducted greenhouse experiments to compare photosynthetic and growth responses of 2 invasive annual grasses (downy brome = Bromus tectorum L. and medusahead = Taeniatherum caput-medusae (L.) [Nevski]), 6 caespitose grasses, and 7 rhizomatous grasses to the herbicide sulfosulfuron (1-(2-ethylsulfonylimidazo[1,2-a]pyridin-3-ylsulfonyl)-3-(4,6-dimethoxypyrimidin-2-yl)urea). Our objectives were...