Efficiency of Inherited Sterility Technique AgainstPhthorimaea operculellaZeller (Lepidoptera: Gelechiidae) as Affected by Irradiation of Females

Abstract

The inherited sterility technique (IST) has been suggested as an alternative control method against the most destructive insect of potato, the potato tuber moth Phthorimaea operculella Zeller. This study was undertaken to assess the effects of releasing females exposed to gamma irradiation on the efficiency of IST. The fecundity, fertility, mating success and frequency of matings of P. operculella females were significantly influenced by gamma irradiation. Completely sterile females were obtained when 200 Gy was applied. The efficiency of using irradiated males and females reached a 98 (biological efficiency index) when a 300 Gy dose of gamma irradiation and a ratio of 1 unirradiated ":1 unirradiated !:10 irradiated ":10 irradiated ! were used. The effectiveness of the inherited sterility technique would be increased when completely sterile P. operculella females together with partially sterile males were used.

Biological Control of <I>Lobesia botrana</I> (Lepidoptera: Tortricidae) Larvae by Using Different Formulations of <I>Bacillus thuringiensis</I> in 11 Vine Cultivars Under Field Conditions

“…Furthermore, it was found that females were more radiosensitive than were males, reduction in female fecundity was greater when they were crossed with males treated at high doses, and F 1 progeny from irradiated males were less fertile than their irradiated parents. These findings are in agreement with those reported for other Lepidoptera species Carpenter et al 2001;Makee and Saour 2004). However, comparing the results of L. botrana male fertility with those obtained from C. pomonella ) and the T. leucotreta , we found that L. botrana was more ra-dioresistant than these two tortricid species (400 vs 350 Gy to obtain full sterility).…”

“…The advantages of F 1 sterility over the completely sterile insect in Lepidoptera pest control were largely discussed by several authors (lower doses of radiation used to induce F 1 sterility increased the quality and competitiveness of the released moths) (Makee and Saour 2004;Carpenter et al 2005;Tate et al 2007;Soopaya et al 2011;Jang et al 2012). Moreover, inherited sterility has been demonstrated in a number of economically important Lepidoptera.…”

Effect of inherited sterility and Bacillus thuringiensis on mortality and reproduction of Phthorimaea opercullela Zeller (Lepidoptera: Gelechiidae)

“…The percentage hatchability of eggs laid by F 1 progeny of irradiated parents was markedly lower than that of nonirradiated parents and did not change regardless of the B. thuringiensis concentration. This proves high sterility in their progeny, which was inherited from irradiated parents, as previously reported (Makee and Saour, 1997, 2003, 2004. The results summarized above prove that a combination of irradiation and B. thuringiensis leads to markedly deleterious effects on the survival and reproduction of F 1 progeny of P. operculella.…”

“…Our previous studies showed that such changes were noticed in F 1 progeny of P. operculella by prolonging the developmental time, reducing fecundity and fertility, and distorting the sex ratio in favor of males (Makee and Saour, 1997, 2003, 2004. In the present study, the efficiency of the integration of such technique with B. thuringiensis application so as to control P. operculella was determined.…”

“…The sterile insect technique (SIT) and inherited sterility technique (IST) are expected as alternative control methods for this pest (Makee and Saour, 1997, 2003, 2004. IST was more effective than SIT in reducing P. operculella populations.…”