The South American tomato moth Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a pest species of great economic importance in tomatoes, both in greenhouses and in open-air crops. This importance has increased in recent years because it has been introduced in many countries in Europe, Africa, and Asia. Insecticides different active ingredients and biological control agents are being used in the control of this pest species. This implies the need to make both groups compatible within IPM programmes. Therefore, the objective of this work was to study the compatibility between different insecticides and the use of the egg parasitoid Trichogramma achaeae Nagaraja and Nagakartti (Hymenoptera: Trichogrammatidae). Three groups of trials were carried out under laboratory and greenhouse conditions. Ten insecticides with the following active ingredient were evaluated: abamectin, azadirachtin, Bacillus thuringiensis, chlorantraniliprole, emamectin, flubendiamide, indoxacarb, methomyl, spinosad, and spiromesifen. In the results, three groups of insecticides were established based on their compatibility with the use of biological control: The first group (abamectin, B. thurigiensis, flubendiamide, indoxacarb and spiromesifen) showed a high degree of compatibility with egg parasitoid releases. The second group (azadirachtin and chlorantraniliprole, and methomyl) presented compatibility problems. Finally, the last group (emamectin, methomyl, and spinosad) did not apper to be compatible. The results found will allow a better application of IPM programmes in tomato crops for the control of this pest species.

Cannibalism is a common phenomenon among insects. It has raised considerable interest both from a theoretical perspective and because of its importance in population dynamics in natural ecosystems. It could also play an important role from an applied perspective, especially when using predatory species in biological control programmes. The present paper aims to study the cannibalistic behaviour of Nabis pseudoferus Remane and the functional response of adult females. In a non-choice experiment, adult females showed clear acceptance of immature conspecifics as prey, with relatively high mortality values (51.89 ± 2.69%). These values were lower than those occurring for heterospecific prey, Spodoptera exigua Hübner, under the same conditions (80.00 ± 2.82%). However, the main result was that the rate of predation on heterospecific prey was reduced to 59.09 ± 7.08% in the presence of conspecific prey. The prey-capture behaviour of adult females differed when they hunted conspecific versus heterospecific prey. This was shown in the average handling time, which was 23.3 ± 3.3 min in the first case (conspecific) versus 16.6 ± 2.5 min in the second (heterospecific). Furthermore, the values increased in the former case and declined in the latter according to the order in which the prey were captured. The difference in handling time was not significant when adjusting the adult female functional response to conspecific nymphs. We argue that these results likely indicate risk aversion and a fear of reprisal among conspecifics.

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