With regard to the importance of antioxidants in foods, cosmetics and pharmaceutics, there are several studies on natural resources for finding rich sources of antioxidants and their role in protecting the body against oxidative stress injuries. The purpose of this study was to investigate the antioxidant stability of arbutin and the Pyrus boissieriana buhse Leaf extract and their effects on li...

BACKGROUND AND AIMS Changes in rainfall and temperature brought about through climate change may affect plant species distribution and community composition of grasslands. The primary objective of this study was to test how manipulation of water and temperature would influence the plasticity of stomatal density and leaf area of bluebunch wheatgrass, Pseudoroegneria spicata. It was hypothesized ...

Transient lulls in air movement are rarely measured, but can cause leaf temperature to rise rapidly to critical levels. The high heat capacity of thick leaves can damp this rapid change in temperature. However, little is known about the extent to which increased leaf thickness can reduce thermal damage, or how thick leaves would need to be to have biological significance. We evaluated quantitat...

We evaluated the effects of cadmium and temperature on plant-litter decomposition by examining diversity and activity of aquatic fungi and leaf consumption by Limnephilus sp., a typical invertebrate shredder of Iberian streams. Freshly fallen leaves were immersed in a stream to allow microbial colonization, and were exposed in microcosms to a gradient of cadmium (≤11 levels, ≤35 mg L(-1)). Micr...

Tobacco plants (Nicotiana rustica L.) pre-exposed to leaf dehydration, mineral deprivation, salination, or BO(3) (3-) toxicity exhibited increased resistance to subzero temperature and to reduced oxygen in the root medium. The stressed plants all showed an elevated content of leaf abscisic acid. Upon transfer of mineral deprived and salinated plants to prestress conditions, a decline in leaf ab...

Nutrient (N) stress affects cotton growth, primary physiological processes andfiber properties. This study utilized two sunlit growth chambers to compare cotton(cv. TM-1) responses to two levels of N nutrition imposed at the onset of floweringstage of development, 100 and 0% of optimum N, in plants grown under otherwiseoptimal temperature and soil moisture conditions. Flowers and bolls were tag...

To examine how the major elements of global change affect herbivory in agroecosystems, a multifactorial experiment was conducted where soybeans were grown at two levels of carbon dioxide and temperature, including those predicted for 2050, under otherwise normal field conditions. Japanese beetles (Popillia japonica Newman) were enclosed on foliage for 24 h, after which the beetle survivorship, ...

The possible alleviating effects of salicylic acid on protection of cowpea (Vigna unguiculata) cv. Parastu under water stress conditions were investigated in the University of Zanjan Agriculture Research Station during 2008. Water stress was imposed by withholding irrigation at 50% flowering (flowering water stress, FWS) and when 50% of the pods grew 2-3cm (pod-formation water stress, PFWS). Sa...