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ARS Home » Southeast Area » Tifton, Georgia » Crop Protection and Management Research » Research » Publications at this Location » Publication #306870
Title: Mating compatibility and competitiveness between wild and laboratory strains of Eldana saccharina (Lepidoptera: Pyralidae) after radiation treatment

Author
item MUDAVANHU, PRIDE - Agricultural Research Council Of South Africa
item ADDISON, PIA - Stellenbosch University
item Carpenter, James
item CONLONG, DES - Stellenbosch University

Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/30/2015
Publication Date: 6/1/2016
Citation: Mudavanhu, P., Addison, P., Carpenter, J.E., Conlong, D. 2016. Mating compatibility and competitiveness between wild and laboratory strains of Eldana saccharina (Lepidoptera: Pyralidae) after radiation treatment. Florida Entomologist. 99(spl):54-65. doi:10.1653/024.099.spl08.

Interpretive Summary: The efficacy of the sterile insect technique (SIT) applied as part of area-wide integrated pest management (AW-IPM) programs is dependent on the quality and the ability of sterile males to search for and mate with wild females. Eldana saccharina (Lepidoptera: Pyralidae) is an economic pest of sugarcane targeted for management using the SIT. As part of further steps towards the development of this control tactic, the level of mating competitiveness and compatibility were assessed by observing the extent to which individuals from different populations interbreed when confined together under both laboratory and semi-field conditions. Three types of pair-wise competition trials were conducted namely laboratory reared vs. wild, 200 Gy irradiated vs. wild and laboratory reared vs. irradiated moths. The data from these tests were used to generate simple indices for tracking mating performance and measuring sexual compatibility between strains. Irrespective of location of trials, wild moths did not discriminate against either the irradiated or laboratory reared moths indicating no ill-effects due to mass rearing or radiation treatment. In general, the irradiated males mated significantly more than their wild counterparts regardless of the type of female, indicating that they are still as competitive as their wild counterparts. The mating indices generated showed no evidence of incipient pre-mating isolation barriers or sexual incompatibility with the wild strain. The data presented in this paper therefore indicates that there is scope for further development of the SIT as an addition to the arsenal of tactics for the AW-IPM of this economic pest.

Technical Abstract: The efficacy of the sterile insect technique (SIT) applied as part of area-wide integrated pest management (AW-IPM) programmes depends on the efficient transfer of sperm carrying dominant lethal mutations from sterile males to wild females. The success or failure of this strategy is therefore critically dependent on the quality and the ability of sterile males to search for and copulate with wild females. Eldana saccharina (Lepidoptera: Pyralidae) is an economic pest of sugarcane targeted for eradication using the SIT and as part of further steps towards the development of the technique, the level of mating competitiveness and compatibility were assessed by observing the extent to which individuals from different populations interbreed when confined together under both laboratory and semi-field conditions. Three types of pair-wise competition trials were conducted namely laboratory reared vs. wild, 200 Gy irradiated vs. wild and laboratory reared vs. irradiated moths. The data from these tests were used to generate simple indices for tracking mating performance and measuring sexual compatibility between strains. Irrespective of location of trials, wild moths did not discriminate against either the irradiated or laboratory reared moths indicating no ill-effects due to mass rearing or radiation treatment. In general, the irradiated males mated significantly more than their wild counterparts regardless of the type of female indicating that they are still as competitive as their wild counterparts. The mating indices generated showed no evidence of incipient pre-mating isolation barriers or sexual incompatibility with the wild strain. The data presented in this paper therefore indicates that there is scope for further development of the SIT as an addition to the arsenal of tactics for the AW-IPM of this economic pest.