Background In the Romanian flora, several species of the Betula genus are present, especially European white birch (B. pendula, syn. B. verrucosa) and downy birch (B. pubescens, syn. B. alba). Rare species are B. nana and B. humilis. In Southern Romania, the sensitization to Betulaceae pollen in patients with allergic rhinitis is less frequent than that to Poaceae pollen. The flowering season o...

The diversity of modern herbivorous insects and their pressure on plant hosts generally increase with decreasing latitude. These observations imply that the diversity and intensity of herbivory should increase with rising temperatures at constant latitude. Insect damage on fossil leaves found in southwestern Wyoming, from the late Paleocene-early Eocene global warming interval, demonstrates thi...

In search of plant genes expressed during early interactions between Casuarina glauca and Frankia, we have isolated and characterized a C. glauca gene that has strong homology to subtilisin-like protease gene families of several plants including the actinorhizal nodulin gene ag12 of another actinorhizal plant, Alnus glutinosa. Based on the expression pattern of cg12 in the course of nodule deve...