Is this Yellow Dragon Charger Guan Xu ?

[Sydney punchbowls]

I have a Yellow Dragon Charger and it was sold as Guan Xu. I presume this relates to the period of production. Is the charger likely to be of this period and what exactly does Guan Xu mean? The Charger is decorated with underglaze blue with a five clawed dragon among lotus scroll with & outer edge of lingzhi scroll border against an yellow enamel ground. It is 42cm in diameter.  See attachments. Any information appreciated.

[peterp]

This looks like a modern imitation. It has a Ming Xuande mark. A good picture of the bottom and some closeups of the decoration should make it possible to verify this.