霜霉病指的是由真菌中的霜霉菌引起的植物病害。霜霉菌是专性寄生菌，极少数的霜霉菌已可人工培养，如引起谷子白发病的禾生指梗霉、引起白菜霜霉病的寄生霜霉。那么霜霉病该怎么用药呢？
This is most likely one for all you sexy DBAs out there: How would I effieciently model a relational database whereby I have a field in an \"Event\" table which defines a \"SportType\"?
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