Feeding of RK together with yeast hydrolysate to immature Qfly increases mating propensity at young ages and accordingly shows significant potential as a pre-release supplement that might increase the proportion of released flies that attain sexual maturation in Sterile Insect Technique programmes. © 2017 Society of Chemical Industry.

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Tephritid fruit flies are amongst the most damaging insect pests of horticulture globally. Some of the key fruit fly species are managed using the sterile insect technique (SIT), whereby millions of sterile males are released to suppress reproduction of pest populations. Male annihilation technique (MAT), whereby sex specific lures are used to attract and kill males, is often used to reduce wild male numbers before SIT programs commence, providing released sterile males an increased numerical advantage. Overall program efficacy might be improved if MAT could be deployed simultaneously with SIT, continuously depleting fertile males from pest populations and replacing them with sterile males. However, such ‘male replacement’ requires a means of suppressing attraction of released sterile males to lures used in MAT. Previous studies have found that exposure of some fruit flies to lure compounds as mature adults can suppress subsequent response to those lures, raising the possibility of pre-release treatments. However, this approach requires holding flies until after maturation for treatment and then release. The present study takes a novel approach of exposing immature adult male Queensland fruit flies (Bactrocera tryoni, or ‘Qfly’) to raspberry ketone (RK) mixed in food, forcing these flies to ingest RK at ages far younger than they would naturally. After feeding on RK-supplemented food for two days after emergence, male Qflies exhibited a reduction in attraction to cuelure traps that lasted more than 20 days. This approach to RK exposure is compatible with current practises, in which Qflies are released as immature adults, and also yields advantages of accelerated reproductive development and increased mating propensity at young ages.

Banana is considered a short life commodity. Extended storage of bananas can be accomplished when ripening is not induced by a large ethylene exposure. Extension of shelf life banana would be possible by applying different promising postharvest treatments. The present study attempts to investigate the effect, of different postharvest treatments namely modified atmosphere with or without ethylene scavenging chemical (KMnO 4 ), cooling, low temperature and hot water treatment on shelf life and quality of 3 commercially important bananas namely Sabri, Champa and Amritasagar. The two-factor experiment was laid out in completely randomized design with three replications. Sabri, Champa and Amritasagar showed significant differences in time periods to reach successive stages of ripening. Longer period was required to reach ripening stages in variety Sabri than those of Champa and Amritasagar. Postharvest treatments and varieties were found to exhibit significant variation in total soluble solids (TSS) content during storage. The variety Sabri had the highest TSS content than that of Champa and Amritasagar. An increasing trend in TSS contents was observed in all varieties at all stages of ripening. The disease severity and disease incidence wer e greatly influenced by postharvest treatments and varieties during ripening and storage. All the treatments exhibited significant effects in relation to disease incidence. Modified atmosphere packaging with ethylene scavenger (KMnO 4 ) and storage of banana at 15C resulted in reduced disease. Disease incidence was the lowest in Sabri variety than that of Champa and Amritasagar. Different postharvest treatments and varieties showed highly significant variation on shelf life. Results showed that the shelf lives of bananas of the variety Sabri, Amritasagar and Champa were 10.81, 9.00 and 10.11 days, respectively. Sabri had the longest shelf life (16.25 days) than two other varieties. Postharvest treatments exerted significant effects to extend shelf life of bananas. The longest shelf life of 15.58 days was observed in bananas held at 15c temperature. Significant extensions of shelf life were also recorded in fruits held in plastic bags with or without KMnO 4 . Combinedly, the longest shelf life was found in fruits of Sabri variety at 15C. Considering the findings it may be concluded that significant variation existed due to the effects of different varieties and postharvest treatments in respect of prolongation of shelf life and other quality parameters of banana. The she lf life of banana could be extended up to 15.58 days in low storage temperature (15C) and up to 10.91 days in modified atmosphere packaging with KMnO 4 . The longer shelf lives of banana with the above mentioned treatments might be related to the slower changes in physico-chemical compositions.