The Influence of Some Sources of Nitrogen on the Growth and Development of the Phomopsis Incarcerata Pathogen (SACC.) Hohnel

Phomopsis incarcerata, known as the pathogen which caused the dieback of Rosa branches was detected in many orchards in Romania. Our investigations have approached a series of bio-ecological aspects of this pathogen: isolation, purification and obtaining the pathogen; determination and identification of the pathogen; establishing in vitro parameters of fungal development (nitrogen source). The isolate used in this study was obtained from Rosa spp. branches and was cultivated on three culture media: potato dextrose agar (PDA), malt extract agar and water agar which included five amino-acids: cysteine, glycine, beta-alanine, leucine and tryptophan. Leucine and glycine were favorable for the dynamics of the fungus.When the fungus grew on water agar, the sporulation was completely inhibited. The optimum pH values for the growth and creation of the Phomopsis incarcerata are in the range of 4.4-7, so weak to neutral acid.