Pathogenicity of VerticilliumdahliaeandPhialophoracyclaminisfungi on some Solanaceae Family crops and antagonistic effect of local fungal isolate Trichodermalongibrachiatum on these two fungi.

Abstract

This study aimed to evaluate the pathogenicity of Verticilliumdahliae andPhialophoracyclaminis isolates previously isolated and identified on some host crops from family Solanaceae known as hosts to these two fungal pathogens. These experiments were conducted in pots at the Green House of Faculty of Agriculture. Transplants were inoculated by Flooding and injection methods. The effect of TNG1 taken from the local isolate of Trichodermalongibrachiatumwas tested on the growth  of these two pathogens and on three host plants in "the same time" and "after 24 hours" treatments. Results demonstrated that the rate of disease severity caused by V. dahliae was 2.6 of disease index on tomato plants compared to the control, eggplant and pepper plants that showed resistance to this pathogen. Disease severity caused by Ph. cyclaminis was almost at the same rate (2.5) on tomato plants. Results indicated that the inhibition effect of the local isolate (TNG1) of T. longibrachiatum on disease severity of V. dahliae on tomato, pepper and eggplant in pots was noticeable especially, on eggplant and pepper at rates (1.0 - 0.3) in both treatments of adding pathogen and the antagonist:"at the same time" compared to its effect on tomato (5) and on the other treatments. While its effect on Ph. cyclaminis was less especially on tomato (5), on pepper and eggplant better effect was obtained rating (1.7) in "the same time" treatment compared to other treatments of adding antagonistic TNG1. Pepper plants were more resistant to disease infection induced by the two pathogens; it showed better growth than eggplant and tomato. Time of inoculation had no significant difference in reduction of disease symptoms on all host plants especially "after 24 hour treatment". However there was some reduction in disease severity (0.33 on pepper) against V. dahlia compared to application of bio agent(TNG1) and the pathogen in "at the same time treatment. These results showed that the inoculation of tested plants by injection was better than flooding method (1.33 on eggplant) which leads to reduction in disease severity of V. dahlia.

  Key words: Host Plants- Verticilliumdahlia-Phialophoracyclaminis -Trichodermalongibrachiatum -Pathogenicity.