STUDIES ON SOME ROOT ROTS FUNGAL DISEASES OF TURFGRASS IN EGYPT AND THEIR CONTROL

Abstract

Some factors were evaluated for controlling root rots affecting Paspalum vaginatum plants. Fungi belonging to 10 genera were isolated from the diseased plants. The survey showed a difference in the frequency of the isolated fungi. In general, Fusarium semitectum, Helminthosporium tetrmera, Macrophomina phaseolina, Pythium splendens and Rhizoctonia solani were found to be the most frequently isolated fungi. The percentages of post-emergence damping-off caused by the tested fungi were decreased by using all the tested treatments compared with the check ones. Some of physiological studies were carried out using the tested fungi. Several rates of inoculum potential of the tested fungi were studied and found that the percentages of 3 and 4% were the favourable inoculums since they gave 50% infested plants. The root exudates of paspalum plants help fungi to growth under specific conditions. Irrigation regime has an effect on plant health and the daily irrigation is the favorite one. Fertilization with nitrogen sources such as urea, ammonium and ammonium nitrate were evaluated. Biofertilization, such as microbin, phosphoren and potassiumag were studied using the tested fungi in vitro and in vivo. Chitosan and salicylic were also studied in vitro and in vivo. Each of chemical and biological control were studied on paspalum plant in vitro and in vivo. Key words: Paspalum-compost-chitosan-salsylic-biofertilizer