in liquid nitrogen/cry-preservation for long duration

Thanks Mehi,  are there any special  treatments for the isolates before preserve.  

the type of preservation depends on the genus. Phythophtora can be subjected to nitrogen-cry preservation while saproleniales cannot. In saprolegniales the best is to maintain them in cultures with mineral oil at 4 C or in hemp seeds also at 4 C. Some genus such as Aphanomyces are however very tricky and usulally they require weekly passes in agar