First record in Africa of the parasitoid Dolichogenidea gelechiidivoris (Hymenoptera: Braconidae) on tomato leafminer Tuta absoluta (Lepidoptera: Gelechiidae) from tomato fields in Algeria

The Neotropical parasitoid wasp Dolichogenidea gelechiidivoris (Marsh, 1975) (Hymenoptera: Braconidae), one of the most important biocontrol agents of the South American tomato pinworm Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), is reported for the first time from Africa, from tomato grown in open fields and greenhouses in several regions of Algeria. Color photos of specimens from Algeria, Spain and South America, as well as the holotype and one paratype are provided. Morphological and molecular details to better characterize and recognize the species are also provided. We speculate that D. gelechiidivoris arrived accidentally to Algeria from Spain, where it has recently been reported. The consequences for future biocontrol projects against T. absoluta in Africa are discussed.

Insights on solanaceous resistance against tomato leafminer (Tuta absoluta), with emphasis on chemical compounds useful in integrated pest management

For integrated pest management (IPM) and organic farming, breeding resistant varieties is one of the most eco-friendly approaches, that goes along botanicals and other different cultural practices, as the use of companion plants. Among the many pest species that invaded the whole world in the last decades, one of the most frightening is the tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), a devastating pest of cultivated tomato worldwide. Tomato is one of the most important agricultural commodities, including the main mean of subsistence in many countries from Africa and middle East. As chemical pesticides failed to control de pest spread and led to many reports of resistant populations, alternative methods for tomato leafminer management must be quickly developed. Many of such alternatives count on a wide range of chemical compounds. The chemical compounds most often responsible for “constitutive resistance”, synthetized by tomato are methyl-ketones (2-tridecanone), sesquiterpenes (zingiberene), and acyl sugars (acylglucose and acylsucrose) while the chemical compounds produced by other plants, used as isolated substances or mixtures, which have antifeedant, growth inhibiting, repellent, and insecticide effects, are azadirachtin, carvacrol, cinnamaldehyde, citronellal, eugenol, linalool, nicotine, pyrethrin, rotenone, thujone, thymol, α-terpineol, 1.8-cineol, etc. Many of them are already commercially available but their efficacy and use differ widely. Therefore, a deeper understanding of the resistance mechanism of solanaceous species related to chemical compounds and substances important for IPM plans developed against T. absoluta is required by the breeding programs.

Potential of two indigenous strains of entomopathogenic nematodes, (Steinernema feltiae and Heterorhabditis bacteriophora) against the tomato leafminer (TLM), Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), under laboratory and greenhouse environmental bioassay

The tomato leafminer (Tuta Absoluta) is an important pest of tomato crops which have features like; high reproductive potential, Invasive species are major threats to agronomic and natural ecosystems. Based on the pathogenicity of strains, only two isolates effectively show larvicidal activity. The native isolate was obtained from soil samples, collected from Rajgarh, Hamachi Pradesh, India. Petri dish bioassay use nematodes S. feltiae HR1 and H. bacteriophora HR2 species dose (0, 10, 20, 40, 80, 160/ IJs/cm2). The (%) 1st instar larval mortality was ranged from 24.15 to 85.38 %. 2nd instar from 29.87 to 90.00 %. 3rd instar from 24.15 to 90.00 %. 4th instar from 31.53 to 90.00 % and pupae stage mortality was ranged from 31.53 to 85.38 %. Larvicidal activity after 48- and 72-hours exposure, the S. feltiae and H. bacteriophora (1.0, 1.30, 1.60, 1.90, 2.20/IJs/cm2) showed potent larvicidal activity with LC50, LC75 and LC90 of all instars and pupa show high mortality. The strain inhibits the larval and pupal development 48 to 72 hr exposer time with LC50 range from 05.42 to 23.67, LC75 20.29 to 83.12, LC90 16.52 to 98.89. Green house test is using the seam isolate of EPNs (HR1, HR2) on foliar application it caused by significant mortality results. These studies demonstrate the challenge for invasive species. The local indigenous strains of EPNs (S. feltiae HR1, H. bacteriophora HR2) as a good biocontrol agent against invasive pest of T. absoluta.