Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí lâm nghiệp đề tài: The effects of flooding and Phytophthora alni infection on black alder. | JOURNAL OF FOREST SCIENCE 56 2010 1 41-46 The effects of flooding and Phytophthora alni infection on black alder V. Strnadová K. Cerny V. Holub B. Gregorová Silva Tarouca Research Institute for Landscape and Ornamental Gardening Prủhonice Czech Republic ABSTRACT The influences of long-term flooding and Phytophthora alni subsp. alni infection on the growth and development of 4-year-old Alnusglutinosa black alder saplings were investigated. The black alder saplings were divided into four groups and then subjected to combinations of both factors - flooded and inoculated with pathogen flooded non-inoculated non-flooded inoculated and control. The biomass of the living roots and actinorrhizae increase in stem length length of leaves rate of chlorotic foliage amount of foliage biomass and length of stem necrosis were assessed after seven weeks. Both factors flooding and P alni infection significantly affected the black alder. In addition a significant effect of interaction was observed. The inoculated flooded group had a substantially lower biomass weight of living roots actinorrhiza and leaves than the other groups. The necroses caused by the pathogen in the flooded group were more extensive than those in the non-flooded one. These findings demonstrate that the simultaneous incidence of stress caused by flooding and P alni infection is highly dangerous for black alder. Keywords alder decline Alnusglutinosa flooding Phytophthora alni In August 2002 the west part of the Czech Republic was afflicted with flooding that exerted stress on hundreds of kilometres of riparian alder stands in several catchments especially in western middle and southern Bohemia. The flooding or total water saturation of soil lasted for several weeks or months in many of the affected areas. In the years following the floods the extended alder population appeared to decline in many of the affected riparian stands which had been healthy prior to the floods Strnadová et al. 2006 . Therefore it was .
