Although many crops have developed several adaptation mechanisms that allow them to defend against limiting factors, some biotic and abiotic stresses may cause reversible or irreversible changes in plants. Among the biotic stresses, the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is probably one of the main important pests that negatively affect several vegetable crops that are grown in greenhouses. The present study evaluated its impact on the morphology and physiology of two solanaceous plants, i.e., tomato (Solanum lycopersicum L.) and eggplant (S. melongena L.), under laboratory conditions. The results showed that, for tomatoes, plant height, shoot dry weight, leaf area, and indirect chlorophyll content were strongly reduced in infested plants, compared to the uninfested control, by 39.36%, 32.37%, 61.01%, and 37.85%, respectively. The same has been shown for eggplant, although the reduction percentages of plant height, root dry weight, and indirect chlorophyll content were less marked (i.e., 16.15%, 31.65%, and 11.39%, respectively). These results could represent interesting information for a better understanding of the B. tabaci influence on plant growth, as well as for the development of management strategies to successfully control its infestations in a cropping system.

Tomato leaf curl New Delhi virus (ToLCNDV) is a bipartite begomovirus (genus Begomovirus, family Geminiviridae) persistently transmitted, as with all other begomoviruses, by whiteflies (Hemiptera: Aleyrodidae) of the Bemisia tabaci cryptic species complex. The virus, originally from the Indian subcontinent, was recently introduced in the Mediterranean basin, where it is currently a major concern for protected and open-field horticulture. The Mediterranean ToLCNDV isolates belong to a novel strain named “Spain strain” (ToLCNDV-ES), which infects zucchini and other cucurbit crops but is poorly adapted to tomato. Recently, it has been reported that another whitefly, Trialeurodes vaporariorum, is able to transmit an isolate of ToLCNDV from India which infects the chayote plant, a cucurbit. The present work aimed to clarify some aspects of whitefly transmission of ToLCNDV-ES. It was shown that T. vaporariorum is not able to transmit ToLCNDV-ES between zucchini plants. In addition, Ecballium elaterium may not act as a relevant reservoir for this virus strain in the Mediterranean basin, as B. tabaci Mediterranean (MED), the most prevalent species of the complex in the region, is not an efficient vector of this begomovirus between cultivated zucchini and wild E. elaterium plants.

This study focuses on the first detection in Europe of a parasitoid Eretmocerus sp. gr. serius (Hymenoptera: Aphelinidae) on the Orange Spiny Whitefly, Aleurocanthus spiniferus (Quaintance) (Hemiptera: Aleyrodidae). Through extensive field surveys, this study investigates the occurrence of the aphelinid in several regions across central and southern Italy. Different sites were monitored to investigate the Eretmocerus sp. gr. serius parasitization rate on A. spiniferus, shedding light on its potential as a biological control agent against the invasive whitefly pest. The research results offer a hopeful prospect for progressing sustainable and eco-friendly methods in handling A. spiniferus infestations in citrus crops, highlighting the importance of natural enemies in integrated pest management programs. The research emphasizes the importance of the recently discovered parasitoid for European agriculture, paving the way for inventive approaches in pest control and cultivation practices.

This paper provides a first report of Aleurocanthus camelliae, the Camellia spiny whitefly, from Italy. The pest was found on plants of Camellia spp. grown in the nursery. Brief morphological and biological information is provided on this whitefly, as well as some considerations on the phytosanitary measures to be adopted to reduce the potential risk of its spread on ornamental plants in Europe and the EPPO region.

Nowadays, in protected vegetable crops, pest management based mainly on biological control represents the most sustainable alternative to pesticide use. The cotton whitefly, Bemisia tabaci, is one of the key pests that negatively impact the yield and quality of such crops in many agricultural systems. The predatory bug Macrolophus pygmaeus is one of the main natural enemies of the whitefly and is widely used for its control. However, the mirid can sometimes behave as a pest itself, causing damage to crops. In this study, we investigated the impact of M. pygmaeus as a plant feeder, by analyzing the combined impact of the whitefly pest and the predator bug on the morphology and physiology of potted eggplants under laboratory conditions. Our results showed no statistical differences between the heights of plants infested by the whitefly or by both insects compared with noninfested control plants. However, indirect chlorophyll content, photosynthetic performance, leaf area, and shoot dry weight were all greatly reduced in plants infested only by B. tabaci, compared with those infested by both pest and predator or with noninfested control plants. Contrarily, root area and dry weight values were more reduced in plants exposed to both of the insect species, compared with those infested only by the whitefly or compared with noninfested control plants, where the latter showed the highest values. These results show how the predator can significantly reduce the negative effects of B. tabaci infestation, limiting the damage it causes to host plants, though the effect of the mirid bug on the underground parts of the eggplant remains unclear. This information might be useful for a better understanding of the role that M. pygmaeus plays in plant growth, as well as for the development of management strategies to successfully control infestations by B. tabaci in cropping environments.

Bemisia tabaci is a group of cryptic and morphologically indistinguishable species able to cause severe damage to many agricultural and ornamental plants. Among the various species of this complex, the Mediterranean (MED) and Middle East Asia Minor 1 (MEAM1) species stand out as they are highly polyphagous, invasive, easily in acquiring resistance to many insecticides and reproduce quickly. Considering how (1) the geographic distribution of B. tabaci is changing with the ongoing global climate change and (2) no knowledge is presently available on phylogenetics of whitefly endosymbionts in Sicily, a population survey was conducted in the most important horticultural production areas of the island to assess the species composition within the B. tabaci complex, including their endosymbiont community and their geographic distribution. Our results show that the MEAM1 species and two mitochondrial variants of B. tabaci MED are present in pure or mixed populations, the MED Q1 presents the highest level of genetic variability within the MED populations in Sicily, having been found almost across the island and, MED Q2 was nearly exclusively detected in the Ragusa province. MEAM1 individuals were rare and exclusively detected in two localities in the Trapani province. The survey on endosymbionts community revealed the existence of a species specific composition, showing the lowest endosymbiont diversity in MED Q2 populations, typically characterized by only Rickettsia. Moreover, except for Portiera in MEAM1, no sequence variation was found within any endosymbiont sequence. Co‐infection patterns of different endosymbiont species are discussed in the context of their needs for host cell metabolites. The present study defines an updated distribution map of cryptic species and phylogenetic groups of the B. tabaci complex and the first status on the endosymbiont community in Sicily; but it also represents the first report of whitefly endosymbionts sequences not only from Sicily but from Italy as a whole.