Nymphal development, mortality and adult longevity of the plant bug Closterotomus trivialis were studied on two of its major crops (Olea europaea L. cv. 'Koroneiki' and Citrus sinensis L. cv. 'Washington Navel') and four non-crop host plants (Mercurialis annua L., Urtica urens L., Parietaria diffusa M. et K. and Sinapis alba L.) under laboratory conditions (15, 20, 24 and 27 °C ± 0.5%; 60 ± 5% RH; 16L:8D h photoperiod). Results demonstrated that C. trivialis can successfully complete its development on all tested host plants and temperatures, except for U. urens at 15 and 20 ^οC. Mortality rates were generally higher on U. urens, P. diffusa and olive than on S. alba, M. annua and sweet orange. Both temperature and host plant significantly affected the nymphal development of C. trivialis. Specifically, host plant affected the development of nymphs at lower and higher temperatures (15, 20, 27 °C) but not at the optimum (24 °C) for its development temperature. Adults of C. trivialis lived longer on sweet orange, M. annua and S. alba in most tested temperatures compared to U. urens, P. diffusa and olives. Overall, these results suggest a better suitability of M. annua, S. alba and sweet orange compared to U. urens, P. diffusa and olive which were proven to be less suitable host plants, covering partially the nutritional needs of C. trivialis. The estimated lower temperature developmental threshold based on the linear model for C. trivialis was found to be lowest on M. annua (3.30 °C) and highest on P. diffusa (10.7 °C). Τhe assessment of the nymphal development in various host plants and temperatures is particularly important for understanding the biology of C. trivialis and provides useful information to optimize its management strategy under integrated pest management system.

Intensive agricultural management practices (i.e., the burning of pruning residues, the absence of organic amendments) lead to a reduction in organic matter and nutrients in the soil resulting in agroecosystem vulnerability. Implementing a cover crop would provide soil organic matter while increasing nutrition levels in the soil. A mixture of cover crop trial in sandy loam soils under Mediterranean climatic conditions was conducted in a rainfed olive grove in Western Crete. In this study, the dry biomass, macro- and micronutrition, and carbon status of the seeded cover crops (legume and grass) were compared to natural plants in an olive grove. Seeded cover crops were conducted in two sustainable management systems (cover crops solely, and a combination of compost, pruning residues, and cover crops); natural plants were in a conventional system involving soil tillage. In combination with conservation tillage practices, the addition of carbon inputs may improve soil fertility. Results indicate that the dry biomass production and C content of cover crops under sustainable management systems was significantly higher than that of the control. The higher dry biomass production and C content found in cover crops compared to the natural vegetation indicates not only that this type of management provides enhanced carbon storage, but can also potentially lead to a future increase in soil organic matter through decomposition. Higher dry biomass is important in the context of carbon sequestration, and cover crops facilitated carbon storage in this study. In addition, this study suggests that sustainable agricultural management practices would provide significant benefits in terms of nutrient retention and CO₂ fixation, thus improving ecosystems in Mediterranean countries.

The management of Bactrocera oleae (Rossi, 1790) has relied on chemical insecticides, applied as bait or cover sprays. However, concerns over insecticide resistance and environmental impact have driven the search for more effective and eco-friendly alternatives, such as mass trapping. The aim of the study was to assess a novel food-based attractant, derived from Tenebrio molitor Linnaeus, 1758 excreta “Frass”, for its attractiveness to B. oleae adults compared to widely used commercial food-based attractants. Over a four-year period, five field trials were conducted in two organic olive groves in Crete, Greece, using a randomized complete block design with five or six replicate blocks. Results showed that frass-based attractants captured significantly higher number of B. oleae adults than the other tested attractants. Additionally, trap–attractant combinations were assessed to determine the most efficient mass-trapping system. Frass-based attractant deployed in Anel or container traps demonstrated significantly higher attractiveness than all commercial traps and lures tested. The significant advantages of mealworm frass as an attractant highlight its potential to enhance the monitoring and suppression of B. oleae in olive orchards. Its consistent performance, sustainability, and environmental safety make it a promising tool in integrated pest management strategies.

This study investigated the phenology and population dynamics of potential insect vectors of Xylella fastidiosa Wells et al. and other Auchenorrhyncha species in olive and citrus groves of Chania province, Crete, Greece. Although X. fastidiosa has not been reported in Greece, its introduction could cause serious diseases in many crops, including olives and citrus. Olive groves of Olea europaea L. ‘Koroneiki’ were sampled systematically using sweep net and Malaise traps over 24 months. One citrus grove was sampled for one year using a Malaise trap. Sweep net samples were taken from the herbaceous cover, tree canopy, and field borders of olive groves. Auchenorrhyncha were more abundant on the herbaceous cover compared to the canopy and field margins. Aphrophoridae species were mostly found on the herbaceous cover and in low numbers during fall (October–December) and spring (April–May). Cicadellidae species, such as Euscelis spp., were frequently found on the herbaceous cover of both olive and citrus groves. One Aphrophoridae and several Cicadellidae species were recorded in the citrus grove. Altitude was found to influence the population abundance of some Auchenorrhyncha species in olive groves. These results provide information for effective integrated management of insect vectors and their vector-borne pathogens.

Due to the environmental impact and increasing cost of inorganic fertilizers, farmers are exploring alternative fertilization strategies. Tenebrio molitor, otherwise known as the mealworm, is one of the most widely reared insect species for the production of high-quality protein for animals and humans. Mealworm frass (MF), a nutrient-rich byproduct of Tenebrio molitor cultivation, presents a viable option for organic fertilization. To investigate the fertilizer potential of frass, a greenhouse pot experiment was conducted, comparing three levels of MF (MF1, MF2, and MF3 at 20, 40, and 80 g/L soil, respectively), organic compost (ORG), and inorganic fertilizer (FERT). MF gave comparable results to FERT in terms of the measured parameters of vegetation, flowering, and production. ORG also gave comparable results to FERT as far as flowering and production but had significantly lower height compared to it. The MF3 treatment significantly improved the average fruit weight and total yield by 19.56% and 30.81%, respectively, compared to the ORG treatment. The two highest doses of MF outperformed FERT in terms of leaf and soil nutrient status, while MF1 and ORG did not differ from it. Furthermore, MF3 yielded 20% greater fruit weight than MF1. However, MF1 was comparable to FERT in fruit weight, resulting in superior fruit color. These results support reduced-input agriculture by providing data for optimizing soil fertility and nutrient management in crops. The findings of this experiment suggest that MF is a viable alternative to inorganic fertilizers and organic compost for greenhouse cultivation of tomatoes. These results highlight the potential of MF as a circular, bio-based fertilizer capable of maintaining tomato productivity while improving soil fertility under protected cultivation systems.

The study of Auchenorrhyncha species composition in Greek olive orchards is crucial due to the potential threat of Xylella fastidiosa invading the region. Recent studies have begun exploring agricultural landscapes, particularly olive and citrus orchards. From 2016 to 2022, biodiversity surveys were conducted in thirteen olive orchards across three regions of Greece: Peloponnese, Sterea Ellada, and the Northeast Aegean. Malaise traps were installed in each orchard and monitored monthly, supplemented by sweep net sampling in two orchards to capture less mobile species and assess their association with host plants. A total of 14,771 specimens were collected, representing 125 species predominantly feeding on weeds. The dominant species were the Typhlocybinae Hebata decipiens and Zyginidia pullula, while Euscelis lineolata was the most common Deltocephalinae. Aphrophoridae, including Philaenus spumarius and Neophilaenus campestris, were more effectively collected with sweep nets, primarily from Avena sterilis L. This study offers a detailed overview of the Auchenorrhyncha fauna in Greek olive orchards, providing essential insights for developing strategies to prevent the invasion of Xylella fastidiosa.