We assessed changes in ultrastructure, membrane lipid peroxidation and antioxidant systems for cucumbner seedlings subjected to low temperature stress (day/night temperature of 8 oC /5 oC) that had been either pre-treated with 10% PEG for 2 days or not. We found extensive cell structure damage in the non-treated seedlings, whereas the seedlings pretreated with PEG to simulate drought remain...

hydroponic experiments were performed to exam the dynamic change of endogenous proline in rice seedlings exposed to potassium chromate chromium (vi) or chromium nitrate chromium (iii). although accumulation of both chromium species in rice seedlings was obvious, more chromium was detected in plant tissues of rice seedlings exposed to chromium (iii) than those in chromium (vi), majority being in...

It is widely accepted that distributions of plants and animals are broadly constrained by their physiological tolerances to climatic factors (Woodward, 1987, 1990). This generalization is held to be true for species at a variety of spatial scales (Whittaker et al., 2001), although there is a wide recognition that the importance of climate is best expressed at large spatial scales (Rahbek & Grav...

Wormwood sagebrush (Artemisia sieberi Besser) is one of the most widely distributed shrub species in Iran and Turkistan steppes, its establishment on dry lands has generally been proven difficult because of low seedling vigor, inability to compete with herbaceous species, poor seed quality, and altered edaphic conditions. In order to evaluation of planting methods and seedling establishment, se...

Red light treatment of etiolated barley (Hordeum vulgare L.) seedlings causes an increase in the relative abundance of the mRNA for light-harvesting, chlorophyll a/b-binding polypeptides, and a decrease in the relative abundance of the mRNA for the NADPH:protochlorophyllide oxidoreductase. It also increases transcriptional activity of subsequently isolated nuclei for the mRNA for the chlorophyl...

drought and salinity are the most important environmental stresses that are causing adverse effects on natural ecosystems. there are species among iranian natural germplasm that are resistant to environmental harsh conditions. restoring of degraded ecosystems, promoting of biodiversity and increasing of species richness will provide by identifying of these species. almond species with broad eco...

Pathogenic and mutualistic fungi have contrasting effects on seedling establishment, but it remains unclear whether density-dependent survival growth are regulated by access to different types of mycorrhizal fungal networks supported neighbouring adult trees. Here, we conducted an extensive field survey test how pathogenic colonization arbuscular (AM) ectomycorrhizal (ECM) seedlings in a subtro...

a study was conducted in 2010 to investigate the effects of crude oil contaminated soil on biomass accumulation injatropha curcas seedlings in asaba, delta state, nigeria. oil levels used were 0.0, 2.0, 4.0, 6.0, 8.0 and 10.0% w/w. the trial was arranged in a randomized complete block design with four replications and monitored for 12 weeks after transplanting. results showed that contamination...