Mating Compatibility and Competitiveness between Wild and Laboratory Strains of<i>Eldana saccharina</i>(Lepidoptera: Pyralidae) after Radiation Treatment

Radiobiological investigations on the reproductive behavior of female Spodoptera litura (Fabr.) were conducted with the aim of determining the suitable radio-sterilizing dose for females in order to release them along with sub-sterile males for effective implementation of the Inherited Sterility technique against this pest. Calling and copulation duration significantly increased, while mating success, oviposition, fertility and longevity significantly decreased with increasing radiation dose (100–200 Gy) compared to control. In view of the effect of irradiation on mating behavior and reproductive viability of female S. litura, 130 Gy was identified as a suitable radio-sterilization dose. Further molecular studies were conducted to corroborate this dose for female sterilization, along with a higher dose of 200 Gy in order to validate the gradational response of ionizing radiation. GC-MS analysis indicated decreased sex pheromone titer at 130 Gy, which was more pronounced at 200 Gy. Pheromone-associated genes, PBAN and PBAN-R showed decreased expression at 130 Gy, and were drastically reduced at 200 Gy. The fertility-related Vg gene also showed a negative correlation with radiation exposure. Based on these radiation responses of female S. litura, 130 Gy might be considered a suitable dose for complete female sterility and its inclusion in sterile insect programs against S. litura.

Section: Discussionsupporting

confidence: 90%

Effect of Irradiation on Reproduction of Female Spodoptera litura (Fabr.) (Lepidoptera: Noctuidae) in Relation to the Inherited Sterility Technique

Sengupta¹,

Vimal²,

Angmo³

et al. 2022

“…Mating studies in walk-in field cages showed the complete absence of mating barriers between codling moth populations from diverse regions of the world, i.e., Argentina, Armenia, Canada, Chile, New Zealand, Syria, and Switzerland [127]. In addition, 200-Gy irradiated or laboratory-reared E. saccharina showed no negative effects due to laboratory rearing or radiation treatment when tested against wild insects in field cages [128]. A substerilizing dose of 250 Gy administered to C. sinensis males would be adequate for programs that include an IS component based on competitiveness values obtained in field cages [118].…”

Section: Quality Control For Lepidoptera Sit or Ismentioning

confidence: 99%

Advances and Challenges of Using the Sterile Insect Technique for the Management of Pest Lepidoptera

Marec

Vreysen

2019

Over the past 30 years, the sterile insect technique (SIT) has become a regular component of area-wide integrated pest management (AW-IPM) programs against several major agricultural pests and vectors of severe diseases. The SIT-based programs have been especially successful against dipteran pests. However, the SIT applicability for controlling lepidopteran pests has been challenging, mainly due to their high resistance to the ionizing radiation that is used to induce sterility. Nevertheless, the results of extensive research and currently operating SIT programs show that most problems with the implementation of SIT against pest Lepidoptera have been successfully resolved. Here, we summarize the cytogenetic peculiarities of Lepidoptera that should be considered in the development and application of SIT for a particular pest species. We also discuss the high resistance of Lepidoptera to ionizing radiation, and present the principle of derived technology based on inherited sterility (IS). Furthermore, we present successful SIT/IS applications against five major lepidopteran pests, and summarize the results of research on the quality control of reared and released insects, which is of great importance for their field performance. In the light of new research findings, we also discuss options for the development of genetic sexing strains, which is a challenge to further improve the applicability of SIT/IS against selected lepidopteran pests.

“…The use of field cages to assess mating performance and competitiveness of pest insects has gained in importance during the last decade. These cages were originally designed for testing the mating behavior of fruit flies (Drosophilidae) [ 26 , 27 ], but their use has been expanded to tsetse flies [ 21 , 22 , 28 , 29 , 30 , 31 , 32 ], mosquitoes [ 33 , 34 ] and Lepidoptera [ 35 , 36 , 37 , 38 ]. Walk-in field cages have proved to be good substitutes for field studies that are more complex and expensive with many parameters that cannot be controlled.…”

Section: Introductionmentioning

confidence: 99%

Gamma Irradiation and Male Glossina austeni Mating Performance

Beer

Moyaba

Boikanyo

et al. 2020

An area-wide integrated pest management (AW-IPM) strategy with a sterile insect technique (SIT) component has been proposed for the management of African animal trypanosomosis (AAT) in South Africa. In preparation for the SIT, the mating performance of colony reared Glossina austeni males under influencing factors such as radiation dose and the development stage that is exposed to radiation, was assessed under laboratory and semi-field conditions. The radiation sensitivity of G. austeni colonized 37 years ago when treated as adults and late-stage pupae was determined. Radiation doses of 80 Gy and 100 Gy induced 97–99% sterility in colony females that mated with colony males treated as adults or pupae. Males irradiated either as adults or pupae with a radiation dose of 100 Gy showed similar insemination ability and survival as untreated males. Walk-in field cage assessments indicated that a dose of up to 100 Gy did not adversely affect the mating performance of males irradiated as adults or late stage pupae. Males irradiated as adults formed mating pairs faster than fertile males and males irradiated as pupae. The mating performance studies indicated that the colonized G. austeni males irradiated as adults or late stage pupae will still be suited for SIT.