abstract in order to study the effect of planting season (autumn and spring) and plant density on growth traits and flower yield (dry weight of flower) of matricaria (matricaria chamomilla), an experiment was carried out at the research field of agricultural faculty of shirvan, affiliated to ferdowsi university of mashhad. a split plot design with two factors, including planting time and plant ...

BACKGROUND There is a general belief that insect outbreak risk is higher in plant monocultures than in natural and more diverse habitats, although empirical studies investigating this relationship are lacking. In this study, using density data collected over seven years at 40 study sites, we compare the temporal population variability of the leaf beetle Phratora vulgatissima between willow plan...

in order to study the effect of irrigation interval, n fertilization and plant density on yield and yield components of fenugreek, a split-split-plot experiment was conducted in darmian, iran in spring 2010. the experiment was conducted in randomized complete block design with three replications. the main plots were subjected to different irrigation intervals of 5 and 10 days. the sub-plots wer...

the two-spotted spider mite, tetranychus urticae koch (acari: tetranychidae), is an economically important pest of ornamental plant in iran. the population abundance and spatial distribution were studied on five rosa cultivars including maroussia, wendela, elderado, wenedetta, and hot lady during two growing seasons of 2011 and 2012 in greenhouse. the k parameter, index of dispersion, lloyd’s m...

1. Genotypic diversity in plant populations is known to enhance plant performance and ecosystem function. Nonetheless, the effect of genotypic diversity has rarely been examined across a population’s lifecycle despite the expectation that changing conditions, such as population density, will alter the benefits of diversity. 2. We simultaneously manipulated a component of genotypic diversity (ri...

In order to evaluate the possible correlation between the tree density and the human population density, the forested area in Nav Asalem district located in Guilan Province was selected. The descriptors of tree number and basal area per hectare as well as the stand density index were used to determine the tree density, which was conducted from a 2014 forest inventory including 62 cluster (558 p...

pepper is one of the nutrition demanding vegetable. in order to compare n fertilizer uptake and plant numbers per area unit, an experiment was conducted with replications. in which fertilizer was the main factor and included ammonium nitrate in 7 levels (0, 80, 160, 240 kg /ha-1) and 40+40, 80+80, 120+120 kg/ha-1 (in 2 stages i.e. half of these amounts appliedpre planting and the other half of ...

1. As plant invasions pose one of the greatest threats to biodiversity, it is critical to improve both our understanding of invasiveness and strategies for control. Much research into plant invasions and their management, including biological control, assumes strong demographic effects by natural enemies, including herbivores. However, the importance of natural enemies in the regulation of plan...