In your country you might have a Plant Pathology program if so that program would be best for diagnosing your local disease problems and issues.
If you have a smart phone camera that can be used for photographing of the symptoms that would be useful.
In addition take some time to describe the details of the issues would be helpful and specialists on line might be able to give you good potential causal agent identification.
I am Plant Pathologist who has been involved through many years of professional work in diagnosis I certainly would look over your situation and opt in and knowing the background might be able to direct you other resources also.
Best Regards, Paul Reed Hepperly, Plant Pathologist
If you have pure cultures of the fungi, consider to send them to the fungal identification service of the CBS-KNAW Fungal Biodiversity Centre in Utrecht, The Netherlands. They have a team of experienced fungal taxonomists and molecular biology facilities to give an accurate identification of any kind of fungus,