Plants of a single genotype of wild strawberry, Fragaria virginiana Duchesne, were grown with or without fertilizer in high (406 microeinsteins per square meter per second) and low (80 microeinsteins per square meter per second) light. High-light leaves were thicker than low-light leaves and had greater development of the mesophyll. Within a light level, high-nutrient leaves were thicker, but t...

this experiment was conducted to evaluate the effect of the addition of a multi enzyme (natuzyme-p) to corn-soybean based diets and to determine the enzyme's nutrient equivalency on broiler chicks’ performance. ninety six day-old male broiler chicks were randomly assigned to a number of 24 battery cages in a completely randomized design. the chicks were grown up to 6 wk of age. six diets (...

A three-trophic-level model of plankton dynamics with instantaneous nutrient recycling is considered. The model consists of autotrophic phytoplankton, herbivorous zooplankton, carnivorous zooplankton and dissolved limiting nutrient. Conditions are derived such that one or more components of the populations tend to extinction. Persistence criteria for the model are also obtained. As well, the bi...

Nutrient cycling is a ubiquitous feature of ecosystems at all scales, allowing productivity to rise beyond the limits set by external nutrient inputs. Nutrient cycling occurs as a side-effect of the metabolism of a diverse set of species that each performs a step in the recycling loop. Recycling loops can be large and involve many steps. At each step the possibility exists for ‘side-reactions’ ...

A simple food chain which consists of nutrient, prey and predator in which nutrient is growth limiting at low concentrations but growth inhibiting at high concentrations is investigated in this study. It is assumed that the nutrient concentration is separated into internal and external nutrient concentration and only the internal nutrient level is capable of catalyzing cell growth. It is shown ...

salinity is one of the most limitation factors for crop production in agricultural systems due to the toxic effects and preventing water and nutrients absorption, in this research the efficiency of four strains of fluorescent pseudomonads on concentration of nutrient elements in rice was determined, under saline conditions. a pot experiment was carried out based on the factorial completely rand...

Prior to puberty, elevated nutrient intake has been shown to negatively affect prepubertal mammary development in the heifer. The objective of this study was to evaluate the effects of increased nutrient intake on mammary development in Holstein heifers at multiple body weights from birth through puberty. Specifically, this study evaluated the effects of nutrient intake and body weight at harve...

The Tolerable Upper Intake Level (UL) refers to the highest level of daily nutrient intake that is likely to pose no risk of adverse health effects for almost all individuals in the general population. As intake increases above the UL, the potential risk of adverse effects increases. The term tolerable is chosen because it connotes a level of intake that can, with high probability, be tolerated...