Effects of selenium on agronomical characters of winter wheat exposed to enhanced ultraviolet-B.

Enhanced ultraviolet-B (UV-B) is one of the most important abiotic stress factors that can influence almost every aspect of plant. Selenium (Se) can increase the tolerance of plants to stressful environment. The paper mainly reported the effects of enhanced UV-B, Se supply and their combination on agronomical characters of winter wheat under field conditions. Enhanced UV-B caused a marked decrease in chlorophyll content, plant height, spike length, weight per spike, grain yield and protein content, grain nitrogen (N) and iron (Fe) concentration, and increased hydrogen peroxide (H2O2), malondialdehyde (MDA) and proline content, and grain zinc (Zn) and manganese (Mn) concentration under without supplemental Se supply. However, it also decreased plant height, spike length, weight per spike, grain yield and Fe concentration, and increased H2O2 content, grain potassium (K), Zn and Mn concentration under supplemental Se supply. On the other hand, Se supply induced an evident increase in chlorophyll content, spike length, weight per spike, grain yield, grain protein content, grain N, Fe, copper (Cu), and Se concentration under both UV-B levels. Moreover, significant UV-B×Se interaction was found on plant height, chlorophyll, MDA, H2O2 and proline content, and grain protein, N, K, Cu and Mn concentrations in wheat. The obtained results supported the hypothesis that Se supply increased the yield and improved the quality of winter wheat exposed to enhanced UV-B to some extent.

Effects of AM fungi on growth and microelement of Scuteliaria baiealensis under different applied phosphorous levels / 中国中药杂志

The effects of AM fungi on the growth, nutrient uptake and microelement of Scutellaria baicalensis under different applied phosphorous levels in the pot culture were studied. The results showed that applied phosphorous levels had remarkable effect on AM fungal inoculation. Inoculation effect of AM fungi was the best under 0.12-0.18 g x kg(-1) soil. At those levels, the effect of AM fungi on the growth of S. baicalensis was the best, but either lower or higher phosphorous level showed suppressed infecting of AM fungi to S. baicalensis. After inoculation, the contents of biomass, total P, baicalin, total N of root were increased as well as the microelements of K, Ca, Mg, Fe, Zn, but the contents of total N of shoot, N/P were decreased as well as the microelements of Mn, Cu. In conclusion, the growth of host plant and using rate of phosphorus fertilizer can be promoted by inoculation of AM fungi.