Question: query regarding how to treat the ginger before sowing. 
Answer: treat the ginger with one fungicide like saaf/blitox-50/ carboxin 2 gram per liter of water or trichoderma viridi 10 gram/liter of water for 30 minutes. then spread them in a polythene sheeth, dry in shade for two days. on 3rd day sow the ginger  by mantaining a spacing row to row 30 cm and plant to 15 cm.