Selection of insectary plants for the conservation of biological control agents of aphids and thrips in fruit orchards.

This study evaluated the potential of flowering plant species naturally occurring to promote the conservation and early establishment of key natural enemies of aphids and thrips in apple and peach orchards. Flowering plants present in the North East of Spain, a main fruit production area in Europe, were sampled to determine their flowering period and to identify potential natural enemies present on each plant species. Thirty-six plant species were found blooming from early March to late May and provided an array of flowers that might ensure food resources for natural enemies. Among them, six species - Eruca vesicaria (L.) Cav., Cardaria draba (L.) Desv., Euphorbia serrata (L.) S.G. Gmel., Malva sylvestris L., Anacyclus clavatus (Desf.) Pers. and Diplotaxis erucoides (L.) DC. - hosted a high diversity of potential natural enemies of aphids and thrips. Their blooming started early in the season and lasted for several sampling weeks and they were widely distributed. Moreover, they had available nectar even in those species with protected nectaries. Therefore, these plant species can be considered as promising candidates for inclusion in the ecological infrastructure designed for fruit orchards in the study area to promote the conservation of the biological control agents of aphids and thrips.

Development and Biomass Composition of Ephestia kuehniella (Lepidoptera: Pyralidae), Tenebrio molitor (Coleoptera: Tenebrionidae), and Hermetia illucens (Diptera: Stratiomyidae) Reared on Different Byproducts of the Agri-Food Industry.

The aim of this study was to evaluate five agro-industrial byproducts (apricots, brewer's spent grains, brewer's spent yeast, feed mill byproducts including broken cereal grains, and hatchery waste including eggshell debris, fluff, infertile eggs, dead embryos, and egg fluids) or mixtures thereof as food diets of Ephestia kuehniella (Zeller), Tenebrio molitor (L.), and Hermetia illucens (L.). Eleven out of 26 tested combinations allowed the first instar larvae to reach the adult stage. Results showed that bioconversion parameters and biomass composition can vary depending on the diet composition, especially in the case of E. kuehniella and H. illucens, whose nutritional requirements seem more complex than those of T. molitor. Tenebrio molitor was able to develop in almost all byproducts. However, only when T. molitor was fed with suitable mixtures of byproducts the development parameters were similar to those obtained with the standard diet. The best results in terms of bioconversion parameters were obtained by feeding H. illucens with a diet including dried brewer's spent grain, feed mill byproducts and brewer's spent yeast. The larvae of these three species can be considered interesting from a nutritional point of view, because of their high protein and fat content. However, the fatty acids profile of H. illucens larvae, with high proportions of saturated fatty acids, seems less healthy for human consumption compared with those of E. kuehniella and T. molitor.

High CO2 concentration as an inductor agent to drive production of recombinant phytotoxic antimicrobial peptides in plant biofactories.

Cationic α-helical antimicrobial peptides such as BP100 are of increasing interest for developing novel phytosanitary or therapeutic agents and products with industrial applications. Biotechnological production of these peptides in plants can be severely impaired due to the toxicity exerted on the host by high-level expression. This can be overcome by using inducible promoters with extremely low activity throughout plant development, although the yields are limited. We examined the use of modified atmospheres using the increased levels of [CO2], commonly used in the food industry, as the inductor agent to biotechnologically produce phytotoxic compounds with higher yields. Here we show that 30% [CO2] triggered a profound transcriptional response in rice leaves, including a change in the energy provision from photosynthesis to glycolysis, and the activation of stress defense mechanisms. Five genes with central roles in up-regulated pathways were initially selected and their promoters successfully used to drive the expression of phytotoxic BP100 in genetically modified (GM) rice. GM plants had a normal phenotype on development and seed production in non-induction conditions. Treatment with 30 % [CO2] led to recombinant peptide accumulation of up to 1 % total soluble protein when the Os.hb2 promoter was used. This is within the range of biotechnological production of other peptides in plants. Using BP100 as a proof-of-concept we demonstrate that very high [CO2] can be considered an economically viable strategy to drive production of recombinant phytotoxic antimicrobial peptides in plant biofactories.

Impact of the Parasitoids Anisopteromalus calandrae (Howard) and Lariophagus distinguendus (Förster) on Three Pests of Stored Rice.

This study evaluated the ability of pteromalid parasitoids Anisopteromalus calandrae and Lariophagus distinguendus reared on Sitophilus zeamais to control stored product coleopteran pests Sitophilus oryzae, Rhyzopertha dominica and Lasioderma serricorne. In trials of parasitoid treatment with A. calandrae, fewer pests (S. oryzae and R. dominica) emerged than in the control. Parasitoid reproduction was highest with S. oryzae as a host, followed by R. dominica and L. serricorne. In trials of parasitoid treatment with L. distinguendus, fewer pests (S. oryzae, R. dominica and L. serricorne) emerged than in the control treatment. Sitophilus oryzae was the host with the highest rate of parasitoid reproduction, although the greatest level of reduction was seen in R. dominica (i.e., host feeding levels were higher for this host species). For L. serricorne, no L. distinguendus progeny was produced. For both species, parasitoids with significantly longer bodies and tibiae emerged from S. oryzae. These results suggest that both parasitoids have potential for use as biocontrol agents for different coleopteran species that attack stored rice.

Control of Aculops lycopersici with the Predatory Mite Transeius montdorensis.

In this study, the predatory mite Transeius montdorensis (Acari, Phytoseiidae) was tested for the control of the tomato russet mite (TRM) Aculops lycopersici (Acari, Eriophyidae) in experiments with small plants, under semi-field and crop conditions. The releasing strategy consisted of repeatedly introducing the predator together with additional breeding prey. The predator was able to move and disperse to the upper part of the tomato plant where the TRM seeks refuge. At the crop level, significant reductions in TRM populations were observed that resulted in a significantly higher yield compared to the conventional control plot, where pesticides were used to control the pest. Caution should be taken when extreme temperatures or humidity occur as they could be deleterious to the predator population. Hence, crop practices should include the management of environmental parameters in the greenhouse to ensure the success of this TRM-control strategy. In conclusion, this biological approach seems to be an effective measure to control the pest and should be further implemented at crop level.

Impact of Diets Including Agro-Industrial By-Products on the Fatty Acid and Sterol Profiles of Larvae Biomass from Ephestia kuehniella, Tenebrio molitor and Hermetia illucens.

Rearing insects on agro-industrial by-products is a sustainable strategy for the circular economy while producing valuable products for feed and foods. In this context, this study investigated the impact of larvae diet containing agro-industrial by-products on the contents of fatty acids and sterols of Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae), Tenebrio molitor (L.) (Coleoptera: Tenebrionidae), and Hermetia illucens (L.) (Diptera: Stratiomyidae). For each insect, selected diets were formulated using single or combined agro-industrial by-products (i.e., apricot, brewer's spent grain and yeast, and feed mill) and compared to a control diet. Fatty acid profiles showed differences depending on diet composition, but mostly depended on species: H. illucens was characterized by the abundance of C12:0, C16:0 and C18:2, whereas C:16, C18:1(n-9c), and C18:2(n-6c) were predominant in T. molitor and E. kuehniella. Sterols significantly varied as a function of diet composition and species. H. illucens showed low cholesterol levels and high campesterol and ß sitosterol levels (0.031, 0.554 and 1.035 mg/g, respectively), whereas T. molitor and E. kuehniella had high cholesterol and low campesterol contents (1.037 and 0.078 g/kg, respectively, for T. molitor; 0.873 and 0.132 g/kg, respectively, for E. kuehniella).

Can Insectary Plants Enhance the Presence of Natural Enemies of the Green Peach Aphid (Hemiptera: Aphididae) in Mediterranean Peach Orchards?

Conservation biological control could be an alternative to insecticides for the management of the aphid Myzus persicae (Sulzer). To develop sustainable strategies for M. persicae control in peach orchards in the Mediterranean, a 2-yr field experiment was conducted to identify the key predators of the aphid; to determine whether the proximity of insectary plants boost natural enemies of M. persicae in comparison to the resident vegetation; and whether selected insectary plants enhance natural enemy populations in the margins of peach orchards. Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae) and Episyrphus balteatus De Geer (Diptera: Syrphidae) were the most abundant predators found among sentinel aphid colonies, accounting for 57% and 26%, respectively. Samplings during 2015 yielded twice as many hoverflies in M. persicae sentinel plants close to the insectary plants as those close to the resident vegetation. The abundance of other natural enemies in sentinel plants, depending on their proximity to the insectary plants, was not significantly different in either of the 2 yr. Hoverflies hovered more often over the insectary plants than over the resident vegetation and landed significantly more often on Lobularia maritima (L.) Desv., Moricandia arvensis (L.) DC., and Sinapis alba L. (Brassicales: Brassicaceae) than on Achillea millefollium L. (Asterales: Compositae). Parasitoids were significantly more abundant in L. maritima and A. millefollium. The vicinity of selected insectary plants to peach orchards could improve the presence of hoverflies, which might benefit the biological control of M. persicae.

Modelling Processes and Products in the Cereal Chain.

In recent years, modelling techniques have become more frequently adopted in the field of food processing, especially for cereal-based products, which are among the most consumed foods in the world. Predictive models and simulations make it possible to explore new approaches and optimize proceedings, potentially helping companies reduce costs and limit carbon emissions. Nevertheless, as the different phases of the food processing chain are highly specialized, advances in modelling are often unknown outside of a single domain, and models rarely take into account more than one step. This paper introduces the first high-level overview of modelling techniques employed in different parts of the cereal supply chain, from farming to storage, from drying to milling, from processing to consumption. This review, issued from a networking project including researchers from over 30 different countries, aims at presenting the current state of the art in each domain, showing common trends and synergies, to finally suggest promising future venues for research.

Efficacy of Modified Atmospheres on Trogoderma granarium (Coleoptera: Dermestidae) and Sitophilus zeamais (Coleoptera: Curculionidae).

We investigated the efficacy of two types of modified atmospheres (MA) against adults of the khapra beetle, Trogoderma granarium Everts, and the maize weevil, Sitophilus zeamais Motschulsky, under laboratory conditions. Adults of the above species on wheat were exposed to a carbon dioxide (CO2) concentration of 70% or a low oxygen (O2) concentration of 0.1% for durations of 0.67 (16 h), 1, 2, 4, and 6 d and stored in an environmental chamber set at 28 ± 2°C, 70 ± 5% RH, and a photoperiod of 16:8 (L:D) h. After each exposure interval, immediate mortality and knockdown were recorded, and the surviving or knocked down individuals were transferred to normal atmospheres and returned to the environmental chamber, where survival was recorded 7 d later. In addition, after the immediate and delayed mortality counts, all adults were removed from the substrate, and the number of progeny produced was recorded 60 d later. Both MA conditions totally controlled (100% mortality) the adults of T. granarium and S. zeamais immediately after a 6-d exposure or after a 4-d exposure when delayed mortality was taken into account, showing the postexposure effect of the MA. Moreover, high CO2 was more effective than low O2 for S. zeamais, whereas the reverse was true for T. granarium. The 4-d exposure period was crucial for the production of progeny of both species because after that period surviving insects did not produce offspring. Our results show that both MA conditions can be used with success to control these species.

The Contribution of Surrounding Margins in the Promotion of Natural Enemies in Mediterranean Apple Orchards.

(1) Habitat management can enhance beneficial arthropod populations and provide ecosystem services such as biological control. However, the implementation of ecological infrastructures inside orchards has a number of practical limitations. Therefore, planting/growing insectary plants in the margins of orchards should be considered as an alternative approach. (2) Here, we assessed the efficacy of a flower margin composed by four insectary plant species (Achillea millefolium, Lobularia maritima, Moricandia arvensis and Sinapis alba), which was placed on an edge of four Mediterranean apple orchards to attract natural enemies of two apple tree aphids (Dysaphis plantaginea and Eriosoma lanigerum). We also characterized the natural enemies present in the aphid colonies. (3) Our results show that the implementation of a flower margin at the edge of apple orchards attracts predators (Syrphidae, Thysanoptera, Araneae, Heteroptera, Coleoptera) and parasitoids. Parasitoids are the main natural enemies present in aphid colonies in our area. (4) The implementation of the flower margins successfully recruited natural enemy populations, and the presence of parasitoids in the surroundings of the orchards increased the parasitism of D. plantaginea colonies.

Hymenoptera Complex Associated with Myzus persicae and Hyalopterus spp. in Peach Orchards in Northeastern Spain and Prospects for Biological Control of Aphids.

Aphids are a serious pest for peach crops. They have traditionally been managed with insecticides, but there is increasing concern about the risk that insecticides pose to both humans and the environment. As a first step to use biological control in aphid management, we conducted a 3-year field survey in northeastern Spain to determine which parasitoids and hyperparasitoids were most prevalent on two aphids, Myzus persicae (Sulzer) and Hyalopterus spp. Koch, the most harmful to peach trees. We collected 11 parasitoid species from M. persicae, with Aphidius matricariae (Haliday) being the most abundant. Two parasitoid species were also collected from Hyalopterus spp., Aphidius transcaspicus Telenga and Praon volucre (Haliday). Hyperparasitoid species overlapped between these aphids but their relative abundances differed. We also discuss the possible impacts of hyperparasitoids on parasitoid populations. Our results suggest that it would be feasible to implement biocontrol methods for aphids in integrated pest management programmes in peach orchards. There are a number of primary parasitoid species associated with these aphids, and the nearby crops and wild vegetation in the vicinity and within the orchards may provide a suitable habitat for them. Additionally, some of them are commercially available and might be usable in augmentative releases.