Dietary restriction extends lifespan in a variety of organisms, but the key nutritional components driving this process and how they interact remain uncertain. In Drosophila, while a substantial body of research suggests that protein is the major dietary component affecting longevity, recent studies claim that carbohydrates also play a central role. To clarify how nutritional factors influence ...

abstract- the effects of iron (fe) and zinc (zn) treatments on the growth and nutrient composition of chickpea were studied in a greenhouse experiment arranged in a completely randomized design. while the application of fe decreased mean shoot dry weight of chickpea, that of zn had no significant effect on chickpea shoot dry weight. increasing fe levels drastically decreased mn concentration an...

ABSTRACT- The effects of iron (Fe) and zinc (Zn) treatments on the growth and nutrient composition of chickpea were studied in a greenhouse experiment arranged in a completely randomized design. While the application of Fe decreased mean shoot dry weight of chickpea, that of Zn had no significant effect on chickpea shoot dry weight. Increasing Fe levels drastically decreased Mn concentration an...

Diseases have become a primary constraint to sustainable aquaculture, but remarkably little attention has been paid to a broad class of pathogens: the opportunists. Opportunists often persist in the environment outside the host, and their pathogenic features are influenced by changes in the environment. To test how environmental nutrient levels influence virulence, we used strains of Flavobacte...

An important regulator of both primary productivity and respiration is nutrient availability [e.g., Sanudo-Wilhelmy et al., 2001; Bonnet et al., 2008; Mills et al., 2008; Wambeke et al., 2008]. The concentration and ratio of nitrogen, phosphorus, and iron in the surface ocean varies predictably among different oceanic regions. For example, phosphate is often present at very low concentration in...

Interactions between different axes of an organism's niche determine the evolutionary trajectory of a population. An extreme case of these interactions is predicted from ecological theory in Liebig's law of the minimum. This law states that in environments where multiple nutrients are in relatively low concentrations, only one nutrient will affect the growth of the organism. This implies that t...

The effect of community structure on the functioning of the ecosystem is an important issue in ecology due to continuing global species loss. The influence of infaunal community structure on the functioning of marine systems is proposed here to act primarily through bioturbation of the sediment. Nutrient concentration in the water column, generated by release from the sediment, was used as a me...

this study was conducted to choose the best species for plantation on a poor drainage soil in southern coast of caspian sea, iran. nutrient concentrations in live and senescent leaves and soil properties were compared among alnus subcordata c.a.mey (n-fixing tree), populus deltoides­ marsh. (non n-fixing tree)and taxodium distichum (l.) rich. (coniferous tree) plantations. in each of these plan...

abstract nitrogen is a key nutrient in plant growth and it is necessary for amino acid synthesis. sulfur has very important role in the biosynthesis of the alliums flavor and pungency precursors and potassium improve crop yield and quality. in order to study the effect of ammonium nitrate and potassium sulfate on concentration some of the mineral elements in onion (allium cepa l. azar shahr cv....