1. The body tissues of insect herbivores contain higher concentrations of nitrogen and phosphorus than do their host plants, leading to an elemental mismatch that can limit herbivore growth, fecundity and ultimately influence population dynamics. While low nutrient availability can limit herbivore growth and reproduction, nutrient levels that exceed an organism’s nutritional requirements, i.e. ...

the present study aimed at investigating the effect of different levels of nitrogen on yield and yield components of bread and durum wheat. to this end the experiment was conducted in 2010-2011 in south west of iran as split plots based on randomized complete block design with three replications. main plot included four levels of nitrogen 60, 120, 180, 240 kg.ha-1 and the sub plot included four...

abstract lettuce is one of the best accumulators of heavy metals and nitrate between leafy vegetables. through this research, it was tried to decreased cadmium absorption with humic acid (ha) and studies the effect of ha on the accumulation and metabolism of nitrate. plants were grown in the peat/perlite and irrigated with hoagland solution with addition of cadmium (2 and 4 mg l -1) and ha (100...

in order to study the qualitative and quantitative yield and some agronomic characteristics of sunflower (helianthus annus l.) in response to seed inoculation with pgpr under various levels of nitrogen fertilizer, a factorial experiment was conducted based on a randomized complete block design with three replications in field experimental university of mohaghegh ardabili during growing season o...

This research compares the performance of floating systems planted with Vetiveria zizanioides as a hydroponic approach for removing nutrients from two contaminated waters. For this purpose, two pilots with overall net volume of 60 litres were constructed and inoculated by secondary treated domestic wastewater (STDW) and irrigation water obtained from Minab reservoir (IWMR) in batch mode. Regard...

an experiment was conducted as randomized complete block design with three replications and 14 fertilizer treatments in year 2014. the treatments were including the control, application of chemical fertilizers according the soil analysis, application of 15, 30 and 45 tons of municipal  waste compost per ha as simple and with 25, 50 and 75% of chemical fertilizers. the results revealed that the ...

abstract in order to evaluate the effect of different nitrogen application methods on yield and yield components of winter wheat, a field experiment with split plot arrangement in completely randomized blocks design with four replicates was conducted in 2006. basal dressing in three levels (1- with no basal dressing, 2- strip and 3- distributing nitrogen fertilizer) as main plot and top dressin...