Initially, a single white or cream line parallel to the midrib occurs, which can be seen from either side of the blade. Later, several straight white to light green to yellow stripes develops parallel to the midrib develop extending along the entire leaf length, but rarely onto the upper portion of the leaf sheath. The stripe wide ranges from narrow pin stripe to as broad as the leaf. A mottled pattern of normal or light green dot, spot, streak or patch islands may develop on a white background, varying in size and shape. If there are many green islands, the leaves will look green. As the disease develops, the plant vigour decreases. Others symptoms are stunted stalks, absence of side shoots on the upper part of infected stalks and abnormal tillering (Ling 1962).
Pleomorphic Phytoplasma bodies have been observed in sieve tube elements of infected sugarcane. They vary in size from 80 to 800 nm, do not have a wall cell and their membrane is approximately 10 nm thick (Maramorosch et al. 1975).
The disease can be detected by PCR-based methods (Wongkaew et al. 1997). Detection of Phytoplasma infection can be accomplished in crude tissue extracts by serological methods (ELISA) (Sarindu & Clark 1993).
According to Ritthinson (2004), the 210 bp phytoplasma DNA fragment associated with sugarcane white leaf disease was detected in 12 out of 69 species of leafhoppers: Baclutha rubrostriata, Balclutha sp., Bhatia olivacea, Exitianus indicus, Macrosteles strifrons, Matsumuratettix hiroglyphicus, Recilia sp., Recilia distinctus, Recilia dorsalis, Thaia oryzivora, Xestocephalus sp. and Yamatotettix flavovittatus.
Matsumuratettix hiroglyphicus and Y. flavovittatus are able to transmit the disease to healthy plants (Chen 1978, Ritthinson 2004).