The feeding larvae of many echinoids develop long postoral arms relative to body length when food is sparse but relatively short abundant, a response thought adaptively adjust capability. However, in an important recent study, Dendraster excentricus exhibited this food-conditioned plasticity only reared at high density typical laboratory cultures; lower more representative larval densities natu...

in order to investigate the effects of foliar application with plant growth promoters on morphological characteristics of maize (single-cross 704), an experiment with three replications and sixteen treatments conducted with priming and spraying of growth promoters (organser, mas-raiz, dulzee and control)  as factorial based on complete randomized block design. analysis of variance showed that t...

In recent years, many research studies have been conducted on the effects of magnetic field on plants. But certain mechanisms regarding magnetic influences have not been defined yet. In this study, effects of magnetic fields (MF) on the growth parameters and enzyme activities of Helianthus annuus L. were investigated. Sterilized seeds in sterile conditions were exposed to 0, 0.5, 1 and 1.5 mT o...

abstract soil microbiological criteria are a complex reflection of interactive metabolic processes that may not be evaluated only by measuring a single parameter but rather it requires the simultaneous determination of more parameters and combining them. the objective of this research was to study enzyme activities: microbial biomass carbon ratios in salinized and none-saline soils in the prese...

wheel numeric and different versions of mobility numbers are important models for predicting the rolling resistance. in this study, data related to the rolling resistance of cross ply and radial ply tires were compared with the resultant values from several models. also, the preciseness of models in rolling resistance prediction was evaluated. for this purpose f test and 1-1 line method (p≥ 0.0...

this study was conducted to determine the effect of variable nitrogen supply on yield parameters of two sugar beet varieties, as well as on biomass allocation to different parts of sugar beet plant at safi-abad agric. res. center during 2003-4 and 2004-5. five nitrogen rates (0, 60, 120, 180 and 240 kgha-1) and two monogerm sugar beet varieties (shirin and rasol) arranged as factorial in a rand...

in order to evaluate the effect of different levels of sowing dates and plant density on grain yield and its components in chickpea var. arman, a field study was conducted at ekbatan research field station of agricultural and natural resources research center of hamedan province under rainfed condition during 2009-2010 cropping season. treatments were arranged as split plot on the basis of rand...