General biology of Eldana saccharina (Lepidoptera: Pyralidae) : a target for the sterile insect technique
CITATION: Walton, A. J. & Conlong, D. E. 2016. General biology of Eldana saccharina (Lepidoptera: Pyralidae) : a target for the sterile insect technique. Florida Entomologist, 99(1):30-35.
The original publication is available at http://journals.fcla.edu/flaent
Eldana saccharina Walker (Lepidoptera: Pyralidae: Gallerinae) occurs on many graminaceous crops and several wild grasses and sedges throughout Africa. It has been reared at the South African Sugarcane Research Institute (SASRI) since the 1970s to study its biology and behavior, as a host for natural enemies and to provide insect material for the plant breeding program. Studies were completed on laboratory-reared E. saccharina of South African origin to assess fecundity, fertility and male and female mating frequencies. Mean fecundity of E. saccharina was 518 ± 27.5 (mean ± SE) eggs per female, up to a maximum of 798 eggs. Mean egg hatch (fertility) of E. saccharina was 63.2 ± 4.2%. In the laboratory, 56.7% of E. saccharina females mated only once but on average females mated 1.5 ± 0.1 times (maximum of 3). Males mated with a maximum of 6 females per male but on average males mated 3.3 ± 0.7 females. Most matings (93%) occurred on the first and second nights after male emergence, and the females oviposited most of their eggs (49.9 ± 3.9%) on the second night after emergence. Eldana saccharina’s high fecundity confirmed its potential as a crop pest. This study has, for the first time, confirmed that male and female E. saccharina were able to mate more than once under controlled laboratory conditions. This has important implications for calculating required release rates of sterilized males to obtain adequate sterile to wild male over-flooding ratios in area-wide integrated pest management programs that have a SIT component.