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Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is the most destructive pest of tomato worldwide. Biological control has always been considered as a promising management approach of this pest in tomatoes. In this context, we evaluated the effectiveness of releasing Trichogramma cacoeciae Marchal parasitoids or Macrolophus pygmaeus (Rambur) predators in controlling T. absoluta in greenhouse tomatoes of northeastern Tunisia. Two weekly releases of either M. pygmaeus at 1 adult/m2 or T. cacoeciae at 20 adults/plant were assessed. Our results indicated that parasitism rates were significantly higher on the apical tomato leaves compared to the middle leaves. We found that the number of T. absoluta eggs and larvae was significantly reduced after releasing T. cacoeciae, while releases of M. pygmaeus did not significantly reduce T. absoluta densities. The present study demonstrated the great potential of releasing T. cacoeciae in controlling T. absoluta in greenhouse tomatoes of northeastern Tunisia. However, further studies are needed to evaluate other release rates of M. pygmaeus that could show promising effectiveness against T. absoluta in northeastern Tunisian greenhouses. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a serious threat to tomato and can occur on other solanaceous crops worldwide. Here we evaluated the development time, fecundity and longevity of T. absoluta on three different host plant cultivars grown in Tunisia: tomato (cv. "Sankara"), potato (cv. "Spunta") and eggplant (cv. "A336"), under controlled laboratory conditions. Results showed a higher capacity of T. absoluta to develop on tomato with a shorter development time (about 31 days) and a higher fecundity (20.47 eggs per female) and longevity (14 days) compared to developing on either potato or eggplant. The development time (egg to adult) of T. absoluta on tomato plant was longer at both lower temperature (21 °C), as compared to the higher 28 °C, and higher relative humidity (either 52 or 72%), as compared to the lower 32% relative humidity. Fecundity of T. absoluta females on tomato plant was highest at 28 °C and 52% relative humidity, as compared to that obtained at 21 °C. The present study provides evidence that host plant, temperature and relative humidity are factors that greatly influence key biological parameters of T. absoluta. The obtained results would be useful for developing and implementing suitable control strategies for this major economic pest. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Meyrick) is a key insect pest of tomato crop causing major economic losses worldwide. Biological control using Trichogramma parasitoids is considered a promising, eco-friendly management tactic of this pest. We performed inundative releases of Trichogramma cacoeciae (Marchal) (Hymenoptera: Trichogrammatidae) against T. absoluta in Takelsa (northeastern Tunisia). Three weekly releases of either (i) 10, 20 or 30 Trichogramma per plant in protected (greenhouse) tomato crops or (ii) 20 or 40 Trichogramma per plant in open field tomatoes were evaluated for their effectiveness. Results indicated that 20 Trichogramma per plant was the most effective release rate in significantly decreasing the pest's life stage densities. Parasitism rates were significantly higher on apical tomato leaves (estimated at 58.6% for the rate 20 Trichogramma per plant in greenhouses and at about 56% for the rate 40 Trichogramma per plant in open field) compared to those observed on middle leaves (24.6% and 45.26% for rate 2 respectively under greenhouse and open field conditions). Furthermore, the overall number of T. absolua eggs and larvae was significantly reduced after releases of Trichogramma parasitoids. These results clearly indicate that T. cacoeciae could be a promising biocontrol agent of T. absoluta in the largest tomato-producing area in Tunisia. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a devastating invasive pest of tomato crops in several areas around the world including Africa. Here, we comprehensively review and discuss the relevant scientific knowledge on its occurrence, biological and ecological aspects, fortuitous insect natural enemies, and potential advantages and constraints of pest management scenarios adopted against this pest in tomato crops in both Northern and Sub-Saharan Africa. We conclude the manuscript with a comprehensive research agenda providing future priorities towards sustainable control of this important tomato pest. [ABSTRACT FROM AUTHOR]