Experimental results showed that soil, seeds and sap inoculation did not transmit the disease, but grafting did. However, grafting has never been prastised in cultivation, so the disease is not transmitted by it.

• 试验表明:土壤、种子均不传病,病组织汁液摩擦接种也不传病,人工嫁接可传病,但胡椒栽培一般不采用嫁接,因而不是传病的途径。