How To Win The Fight Against The Eldana Sugar Cane Pest

Eldana has a major negative effect on the yield and quality of sugar cane crops. Dr Des Conlong, senior entomologist at the SA Sugarcane Research Institute, says that only modern integrated pest management can reduce the impact of this pest.

- Lloyd Phillips

The eldana moth species (Eldana saccharina) is endemic to sub-Saharan Africa’s wetland areas, where its caterpillar larvae feed on plants such as papyrus (Cyperus papyrus).

In 1848, commercial planting of sugar cane started in South Africa in areas of water stress close to or in papyrus stands. This set the scene for an invasion by this opportunistic moth into the sweet and juicy sugar cane stalks.

“Eldana’s invasion from the wild into sugar cane in South Africa was first identified in 1939 on KwaZulu-Natal’s Umfolozi Flats,” says Dr Des Conlong, senior entomologist with the South African Sugarcane Research Institute (SASRI). “It then disappeared for some years before being found again in Umfolozi Flats sugar cane fields in the early 1950s.

“Yet again it disappeared until the early 1970s, from which point onwards its widespread invasion of South African sugar cane fields began. By 1994 it was found in all sugar cane-growing areas covering Mpumalanga and KwaZulu-Natal.”

Conlong and other researchers discovered that sugar cane stressed from too much or too little water is highly attractive to female eldana moths as an additional egglaying site and food source for the hatched larvae.

ELDANA’S COSTLY IMPACT

According to a March 2015 SASRI publication, ‘IPM for eldana control’, authored by senior plant pathologist Dr Stuart Rutherford, eldana infestations cause yield and quality losses in sugarcane due to the larvae feeding on the inside of the stalks. Eldana also creates an opportunity for the pathogenic fungus Fusarium to infect plants at sites where eldana larvae have bored into the stalks.

Rutherford writes that between 2002 and 2012 alone, the local sugar cane industry lost an average of R744 million in annual income as a result of the direct and indirect impact of eldana infestations.