Research of the effect of certain biological and chemical applications onthe latent infections of Neofusicoccum parvum and the endophytic fungal microbiome in grapevine seedlings

Neofusicoccum parvum is one of the fungal pathogens that cause seedling death and dieback in grapevine seedlings and mature vines. The eradication of this pathogen, which can be found in a latent state in vines, is not yet possible with fungicides. This study aims to reveal the effects of Certain Biological and Chemical Applications(CBCA)in reducing latent infections of N. parvum and altering the endophytic fungal flora.The standard mycological isolation procedure was followed, and morphological and molecular methods were used to determine the initial flora in dormant 1103 Paulsen grapevine cuttings. The cuttings were inoculated with N. parvum using a drill and planted in pots, then grown outdoors for four months. At the beginning of rooting, liquid worm manure, Reynoutria extract, microbial fertilizer, and various fungicides were applied three times by pouring and three times by foliar spraying, and the mycorrhizal preparation was applied to the rhizosphere twice. After four months, the seedlings were uprooted, and the lengths of internal necrosis and root dry weights were measured. Re-isolation was performed from the stem tissues, and the initial and final flora were compared. Compared to the control, CBCA's significantly reduced necrosis formation, with the highest effect observed in the mycorrhizal preparation.N. parvum could not be isolated from seedlings treated with mycorrhiza or prothioconazole + proquinazid beyond 10 cm from the inoculation point. The ratios of endophytic Trichoderma sp. and Clonostachys rosea increased with mycorrhiza, vermicompost, and Reynoutria extract applications; all CBCA's reduced the isolation of Penicillium species by 70-100%. This study demonstrates that CBCA's can make substantial contributions to the control of latent pathogens and the shaping of endophytic flora in nurseries.