Stressful parental environments can influence offspring size and development either adaptively or maladaptively, yet little is known about species' differences in this complex aspect of phenotypic plasticity. We performed a reciprocal split-brood experiment to compare transgenerational plasticity in response to drought stress in two closely related annual plant species. We raised inbred replica...

In this study, four specimens belonging to Karaj mycoflora were examined. According to the results, two form – species; Diplosporonema delastrei, on Silene latifolia subsp. persica and Piggotia ulmi, on Ulmus sp. are reported with new names. For some of the identified fungal specimens, new hosts (matrix nova) are introduced. Moreover, many taxa such as , Marssonina kriegeriana on Salix sp.,  Se...

Norms of reaction for a number of growth and reproductive characters were determined for 15 randomly sampled Polygonum persicaria genotypes, from two natural populations originating in sites with very different nutrient availabilities. Under severely limiting nutrient conditions, these genotypes shared not only plastic responses such as increased root-to-shoot ratio, but a surprising constancy ...

In this study, the relationship among four species of Polygonum (including P. hyrcanicum (three samples), P. persicaria, P. avicular, and P. hydropiper) was investigated by GC profiling. Furthermore, the major compounds of the ethylic ether extract of P. hyrcanicum were identified by GC/MS as: α-bisabolol (17.5%), cedrol (15.9%), sesquisabinene hydra...

A survey was undertaken in China between 1996 and 2001 for phytophagous insect fauna associated with mile-a-minute weed, Polygonum perfoliatum L. (Polygonaceae). The purpose was to identify potential biological control agents for this invasive plant in the eastern USA. The survey covered 23 provinces including northeastern China, where the climate is similar to that of the eastern USA, and sout...

Factors promoting the evolution of specialists versus generalists have been little studied in ecological context. In a large-scale comparative field experiment, we studied genotypes from naturally evolved populations of a closely related generalist/specialist species pair (Polygonum persicaria and P. hydropiper), reciprocally transplanting replicates of multiple lines into open and partially sh...