Hab'Alim, Shelters and food sources for supporting the beneficial arthropods in greenhouse and outdoor crops

Abstract: In IPM packages, effectiveness of biological control is strongly dependent on the
capacity of natural enemies to stay in the crops, whether these natural enemies have been
released or promoted (through conservation methods). The Hab’Alim project aims to identify
and develop habitats that provide feeding sources and shelters for the predators and the
parasitoids of several greenhouses and outdoor crop pests. The possibility of using natural
materials, companion plants, supplying pollen, as well as food supplements are studied both for their effects on pests and beneficial arthropod populations. Under laboratory conditions, among materials subject to low and high temperatures, the hemp allowed the maintenance of Transeius montdorensis populations. The tests revealed that the lowest survival capacity of phytoseiids was in buckwheat husks. Very encouraging results were obtained in protected crops. Among the natural materials tested, hemp, buckwheat husks and miscanthus have contributed to increase and/or diversify the beneficial fauna on landscape roses. Phytoseiulus persimilis, Neoseiulus cucumeris, Neoseiulus californicus and supplement preys were maintained in buckwheat husks at the base cut-flower roses in greenhouses. In 2021, buckwheat husks applied on the soil improved the dissemination and the number of Phytoseiidae in eggplant organic cultivation. This mulching has improved the control of the cut flower roses’s thrips and of the eggplant’s spiders. Trials on several companion plants have shown encouraging results. Alyssum, Lobularia maritima, optimized the biological control efficiency of Orius laevigatus on strawberries’ aphids. Viburnum tinus and Sorbaria sorbifolia, promote the presence of Syrphidae, parasitoids and Coccinellidae. In eggplant crop, additional feeding (Pollen of Typha angustifolia or Thyreophagus entomophagus) had very little effect on Phytoseiidae. In soilless production of strawberries, three weeks after the last nourishing with T. entomophagus, the population of Amblyseius swirskii and T. montdorensis was higher, however the difference was not significant with the control. In rose cut flowers protected by T. montdorensis, no significant differences have been observed between the control and the combination of buckwheat husks with prey, in terms of rose quality, preservation of phytoseiids and population dynamics of the California thrips. For rose, strawberry and eggplant cultivations, the cost of buckwheat husks is too expensive.
Therefore, it will be interesting to continue studying integrated ecosystems in agrosystems,
to improve the process of natural regulation of crops, at an acceptable cost.