Biology and population dynamics of the potential sugarcane Fiji disease vector Perkinsiella saccharicida (Homoptera: Delphacidae) in Réunion: evidence of its loss of biotic potential

There is a risk that irrigation schemes that have been developed to enhance sugarcane, Saccharum spp, cropping on the island of Réunion could markedly broaden the distribution range in which outbreaks of the insect Persinkiella saccharicida Kirkaldy (Homoptera: Delphacidae), a sugarcane Fiji virus disease vector, have already occurred. This trend was confirmed by the results of laboratory studies and monthly surveys carried out in six sugarcane fields distributed throughout the island. A complex of efficient entomophagous organisms were also observed, including Tytthus spp. (Hemiptera: Miridae), and they were found to be capable of reducing P. saccharicida populations. These latter planthoppers also seemed to have lost part of their biotic potential as compared to those of the same species in its endemic area abroad. It is thus recommended that pest species be carefully monitored in cropping areas where large-scale irrigation schemes have been developed.