Further studies on cocoa yellow mosaic virus

Cocoa yellow mosaic virus from Sierra Leone is readily transmitted by sap to many woody and herbaceous dicotyledonous plants. It is serologically related to wild cucumber mosaic virus and to turnip yellow mosaic virus, and has similar chemical and physical properties. It is stable when frozen or lyophilized, inactivated when kept for 10 min. at 65°, and is precipitated without loss of infectivity in a half-saturated ammonium sulphate solution. The particles appear to be 25 Mμ across when mounted in neutral phosphotungstate, and 29 Mμ when shadowed. All preparations contained infective nucleoprotein particles which sedimented at 108 S, and non-infective protein shells which sedimented at 49 S.