Comparative Efficacy of CO₂and Ozone Gases AgainstEphestia cautella(Lepidoptera: Pyralidae) Larvae Under Different Temperature Regimes

Abstract

Comparative efficacy of three different modified atmospheres: 100% CO2, 75% CO2 + 25% N2, and 22 ppm ozone were examined against larval mortality of the almond moth, Ephestia cautella (Walker) (Lepidoptera: Pyralidae) at temperature regimes of 25°C and 35 ± 2°C and 60 ± 5% relative humidity, and 9:15 dark and light. Wandering young larval instars, which are fast growing, large enough in size and considered as more tolerant to modified atmosphere, were collected directly from the rearing culture, placed inside pitted date fruits of vars.: “Khudri,” “Ruziz,” and “Saqie,” were treated with aforementioned gases for 24, 48, and 72 h. The immediate and delayed larval mortality was recorded after each exposure timing. Ozone possessed the strongest fumigant toxicity causing 100% mortality with all varieties, at 25 and 35°C after 24 h exposure and was more effective than 75% CO2 that caused 83 and 100% immediate mortality with variety ruziz at 25 and 35°C, respectively. Extending the treatments exposure time to 72 h, 100% mortality was recorded by exposing larvae to any of the studied gases at 25 and 35°C. These results suggest that gases and temperature used in this study can be effectively used to control E. cautella in dates and stored grains.

THE EFFECTIVENESS OF CARBON DIOXIDE AND NITROGEN ON DIFFERENT DEVELOPMENTAL STAGES OF Cadra cautella (LEPIDOPTERA: PYRALIDAE)

“…Chemicals such as carbonyl sulfide, sulfuryl fluoride, ozone, cyfluthrin, iodomethane, and nonchemical treatments including modified atmospheres, high pressure, heat/cold treatments, sanitation, radio frequency, long-wave energy and irradiation have been utilized (Desmarchelier et al, 1998;Johnson et al, 2000;Fields and White, 2002;Schneider et al, 2003;Aksoy et al, 2004;Cetinkaya et al, 2006). Several studies have demonstrated that applications of modified atmospheres (MA) and ozone are possible alternatives for methyl bromide against dried fruits pests including C. cautella (Soderstrom et al, 1984;Soderstrom et al, 1986;Navarro et al, 1993;Donahaye et al, 1994;Navarro et al, 1997;Donahaye et al, 1998;Navarro et al, 1998;Navarro et al, 2000, Husain et al, 2015. Application of MA, such as purging with CO2 or N2 are well-known, dependable and proven to be residue-free techniques for disinfestation of food storage products.…”

Comparative efficacy of modified atmospheres enriched with carbon dioxide against Cadra (=Ephestia) cautella

“…Briefly, test stages confined in small PVC vials were exposed to 90% and 96% CO 2 in 550 mL gas‐washing bottles with inlet and outlet valves, each containing 50 mL KOH solution to maintain humidity at a level of 65 ± 3%. The humidity level preferred is the optimum for the development of C. cautella and is in the range between 60%–70% RH that previously used by many authors . Larvae were offered approximately 1 g of the food that was used for insect rearing to prevent starvation and / or cannibalism, whereas other stages were not provided any food.…”

“…Similarly, time to complete mortality for all life stages exposed to ≥ 90% CO 2 (in air) was decreased from 48 h at 27.5 to 36 h at 32.5 °C . However, at higher temperatures, an increase in gas concentration has no further effect on decrease in mortality time, as 4th instar larvae were killed in 24 h at both 75% and 100% CO 2 at 35 °C . Relative humidity is another critical factor for the mortality of C. cautella .…”

“…This study was undertaken to obtain detailed information for the control of different age groups of all immature stages (three different ages for the eggs and pupae, and two different ages for larvae) and adults of C. cautella . Experiments were conducted at 65% RH, which is the optimum level for the development of C. cautella , previously used by many authors . From the point of view of practice, this study was planned to obtain complete mortality in the shortest time possible.…”

Integrated research programs for date palm pest management: New initiatives and future perspectives

“…For the almond moth research program, the application of 100 % CO 2 for at least 48 h at 35 °C or O 3 for 24 h at 25 °C or 35 °C were the most effective methods to control this insect (Table 3 and Table 4) [15]. A further research to incorporate these results in a dates packaging process is still ongoing.…”