Almond hulls and shells, the byproducts of the almond industry, were analyzed to assess their potential valorization pathways. Shells showed a higher content in lignin and polysaccharides, but very low levels of extractives and inorganics. Hull’s high polar extractives fraction showed poor phenolic preponderance and antioxidant activity, but high sugar and mineral contents, and its lipophilic extracts were highly enriched in triterpenes (from 73.5% to 91.3%), while shells presented more fatty acids (27.4% to 34.2%) and sterols (17.4% to 29.1%). Shells exhibited much higher S/G ratio (syringyl to guaiacyl units) in their lignin polymer (1.0 to 1.4), compared to hulls (0.5 to 0.6). After mineral analyses, hulls showed high amounts of potassium (3.7–4.9%). Fixed carbon content was similar for both materials, but shells showed a higher energetic content, ~20 MJ/kg. Finally, both hulls and pellets increased the water holding capacity (WHC) of the soil by 50%, when added in weight percentages of 6.25% (hulls) and 25% (pellets). With these results, the range of possibilities for these waste materials is exciting: shells could be used to obtain hemicellulose oligosaccharides, while hulls could be used in sugar extraction for biotransformation or as a soil amendment.
The chestnut gall wasp (Dryocosmus kuriphilus Yasumatsu) is an invasive pest that attacks species of the genus Castanea, inducing gall formation on buds and leaves, which can significantly reduce tree growth, fruiting, and overall chestnut production. Native to China, D. kuriphilus has become a serious threat to chestnut orchards worldwide. Torymus sinensis Kamijo, a parasitoid also originating from China, is highly specific to D. kuriphilus and is currently considered the most effective biological control agent against this pest. This study aimed to evaluate the establishment of T. sinensis as well as its effectiveness in controlling D. kuriphilus at release sites between 2020 and 2023. Releases of T. sinensis were conducted in the municipality of Bragança with a sex ratio of 120 females to 70 males. The parasitoids were randomly released across three chestnut trees with infestation levels ranging from moderate (26–50% of the canopy affected by galls) to very severe (>80% of the canopy affected). At each release site, 250 galls were collected annually, and 10% of these galls were dissected to calculate parasitism rates by T. sinensis. Results revealed a positive correlation between the monitoring year and the parasitism rate. Following the releases, parasitism rates increased gradually, reaching values between 15% and 40%. T. sinensis successfully established itself in chestnut orchards and parasitized D. kuriphilus, despite normal population fluctuations being observed across years and orchards.
In this work, the objective was to learn the life cycle of D. kuriphilus and the diversity of native parasitoids in the northern region of Portugal between 2017 and 2019. The places studied belonged to the regions of Entre-Douro-e-Minho, Beira Interior, and Trás-os-Montes. To achieve the proposed objectives, buds were collected for egg and larva observation, galls were collected for larva, pupa, and adult observation and monitoring, and emergency boxes were used to identify the fauna present in the galls. In this study, 92% of D. kuriphilus adults emerged between June and July, with emergences occurring until September. We also obtained adults in winter, so it is important to study, in future works, the hypothesis of this pest performing diapause. Regarding the study of native parasitoids, compared to other countries, the same families emerged, with good rates of natural parasitism, although with fluctuations over the years. In the three municipalities under study, 11 species were identified (Eupelmus azureus Ratzeburg, Eupelmus urozonus Dalman, Eurytoma brunniventris Ratzeburg, Megastigmus dorsalis (Fabricius), Ormyrus pomaceus (Geoffroy), Sycophila iracemae Nieves Aldrey, Sycophila variegata (Curtis), Sycophila biguttata (Swederus), Torymus flavipes (Walker), Torymus auratus (Mueller), and Torymus notatus (Walker)). The average parasitism rates varied between 1.92% and 10.68%.
Understanding and accurately predicting stomatal conductance in almond orchards is critical for effective water-management strategies, especially under challenging climatic conditions. In this study, machine-learning (ML) regression models trained on multispectral (MSP) and thermal infrared (TIR) data acquired from unmanned aerial vehicles (UAVs) are used to address this challenge. Through an analysis of spectral indices calculated from UAV-based data and feature-selection methods, this study investigates the predictive performance of three ML models (extra trees, ET; stochastic gradient descent, SGD; and extreme gradient boosting, XGBoost) in predicting stomatal conductance. The results show that the XGBoost model trained with both MSP and TIR data had the best performance (R2 = 0.87) and highlight the importance of integrating surface-temperature information in addition to other spectral indices to improve prediction accuracy, up to 11% more when compared to the use of only MSP data. Key features, such as the green–red vegetation index, chlorophyll red-edge index, and the ratio between canopy temperature and air temperature (Tc-Ta), prove to be relevant features for model performance and highlight their importance for the assessment of water stress dynamics. Furthermore, the implementation of Shapley additive explanations (SHAP) values facilitates the interpretation of model decisions and provides valuable insights into the contributions of the features. This study contributes to the advancement of precision agriculture by providing a novel approach for stomatal conductance prediction in almond orchards, supporting efforts towards sustainable water management in changing environmental conditions.
Almonds are becoming a central element in the gastronomic and food industry worldwide. Over the last few years, almond production has increased globally. Portugal has become the third most important producer in Europe, where this increasing trend is particularly evident. However, the susceptibility of almond trees to changing climatic conditions presents substantial risks, encompassing yield reduction and quality deterioration. Hence, yield forecasts become crucial for mitigating potential losses and aiding decisionmakers within the agri-food sector. Recent technological advancements and new data analysis techniques have led to the development of more suitable methods to model crop yields. Herein, an innovative approach to predict almond yields in the Trás-os-Montes region of Portugal was developed, by using machine learning regression models (i.e., the random forest regressor, XGBRegressor, gradient boosting regressor, bagging regressor, and AdaBoost regressor), coupled with remote sensing data obtained from different satellite platforms. Satellite data from both proprietary and free platforms at different spatial resolutions were used as features in the study (i.e., the GSMP: 11.13 km, Terra: 1 km, Landsat 8: 30 m, Sentinel-2: 10 m, and PlanetScope: 3 m). The best possible combination of features was analyzed and hyperparameter tuning was applied to enhance the prediction accuracy. Our results suggest that high-resolution data (PlanetScope) combined with irrigation information, vegetation indices, and climate data significantly improves almond yield prediction. The XGBRegressor model performed best when using PlanetScope data, reaching a coefficient of determination (R2) of 0.80. However, alternative options using freely available data with lower spatial resolution, such as GSMaP and Terra MODIS LST, also showed satisfactory performance (R2 = 0.68). This study highlights the potential of integrating machine learning models and remote sensing data for accurate crop yield prediction, providing valuable insights for informed decision support in the almond sector, contributing to the resilience and sustainability of this crop in the face of evolving climate dynamics.
Almond cultivation is of great socio-economic importance worldwide. With the demand for almonds steadily increasing due to their nutritional value and versatility, optimizing the management of almond orchards becomes crucial to promote sustainable agriculture and ensure food security. The present systematic literature review, conducted according to the PRISMA protocol, is devoted to the applications of remote sensing technologies in almond orchards, a relatively new field of research. The study includes 82 articles published between 2010 and 2023 and provides insights into the predominant remote sensing applications, geographical distribution, and platforms and sensors used. The analysis shows that water management has a pivotal focus regarding the remote sensing application of almond crops, with 34 studies dedicated to this subject. This is followed by image classification, which was covered in 14 studies. Other applications studied include tree segmentation and parameter extraction, health monitoring and disease detection, and other types of applications. Geographically, the United States of America (USA), Australia and Spain, the top 3 world almond producers, are also the countries with the most contributions, spanning all the applications covered in the review. Other studies come from Portugal, Iran, Ecuador, Israel, Turkey, Romania, Greece, and Egypt. The USA and Spain lead water management studies, accounting for 23% and 13% of the total, respectively. As far as remote sensing platforms are concerned, satellites are the most widespread, accounting for 46% of the studies analyzed. Unmanned aerial vehicles follow as the second most used platform with 32% of studies, while manned aerial vehicle platforms are the least common with 22%. This up-to-date snapshot of remote sensing applications in almond orchards provides valuable insights for researchers and practitioners, identifying knowledge gaps that may guide future studies and contribute to the sustainability and optimization of almond crop management.
The chestnut moth (Cydia splendana Hübner) and the chestnut weevil (Curculio elephas Gyllenhal) cause serious damage to European producers and companies that transform and market the chestnut. The objective of the present work was to evaluate, under field conditions, the possibilities of Beauveria bassiana (Bals.-Criv.) Vuill. to infect and kill the larvae of the two main carpophagous pests of European chestnut, in treatments directed at the soil. For this purpose, the surfaces of vases were sprayed with two concentrations of conidia/mL 5 × 107 (T1) and 1 × 108 (T2). The control (T0) was sprayed with distilled water. Larval mortality and infection were evaluated on five dates (D8 to D220). Confirmation of the fungus present in the larva was performed by molecular analysis. The results obtained are promising for the use of B. bassiana as a biological control agent against these key pests of the chestnut crop. There were no significant differences in mortality between the T1 and T2 modalities, however, they were significantly higher than the control. In the case of total mortality (dead and infected larvae), no significant differences were observed for C. elephas either. In the case of C. splendana, the T2 modality obtained better results in terms of total mortality.
Irrigation is the best strategy to reduce the adverse effects of water stress on almond trees [Prunus dulcis (Mill) D.A. Web] and improve their productivity. However, in the current context of climatic change, in which the amount of water available for irrigation is increasingly limited, deficit irrigation (DI) strategies have become essential in the almond orchards of southern Europe. Other practices, such as the foliar application of reflective compounds, are being implemented. A three-year experiment (2019–2021) was set in a factorial design in which the effect of regulated deficit irrigation and foliar kaolin spray was evaluated on physiological (predawn leaf water potential, relative water content, leaf area, leaf gas exchange, and chlorophyll fluorescence) and agronomic parameters (yield, yield components, and water use efficiency (WUE)). The treatments include full irrigation (FI), which received 100% of ETc (crop evapotranspiration) during all irrigation seasons; regulated deficit irrigation (RDI), which received 100% of ETc until the kernel-filling stage, reducing the application to 35% ETc during the kernel-filling stage until harvest; and both irrigation regimes combined with kaolin application and two cultivars, Constantí and Vairo. More negative water potential values were observed in the RDI treatments compared to the FI treatments. There were no significant differences in the stomatal conductance, photosynthetic rate, or transpiration rate between treatments with RDI and FI, demonstrating the almond tree’s good adaptation to irrigation reduction in the kernel-filling stage. The two cultivars had different responses in cumulative yield throughout the three years of the trial. The cv. Constantí did not present significant differences between the FI and RDI treatments, translating into improved WUE. In contrast, the cv. Vairo suffered a reduction in accumulated performance in the RDI treatments with respect to the FI. The foliar application of kaolin did not present differences in yield and very few in the physiological activity of the almond trees. With the results obtained, we can suggest that under the conditions of our experiment, the combination of RDI and the kaolin foliar application can help save irrigation water and produce almonds more sustainably.
Almond trees in Portugal are susceptible to aphid infestation, which can result in reduced fruit production. To effectively tackle this issue, the combination of remote sensing (RS) data and machine learning (ML) classifiers can be used to accurately detect the presence of aphids. This study focuses in the implementation of ML classifiers and RS data analysis to identify aphids on almond trees, using high-resolution multispectral data collected through an unmanned aerial vehicle (UAV) in a Portuguese almond orchard. Four ML classifiers, kNN, SVM, RF and XGBoost, were employed and fine-tuned using vegetation indices derived from spectral data. The results revealed that the SVM classifier achieved an overall accuracy (OA) of 77%, followed by kNN with an OA of 74%, while XGBoost and RF achieved OAs of 71% and 69%, respectively. Consequently, this study demonstrates the viability of employing RS data and ML classifiers for aphid identification in almond orchards.
In the last decade Unmanned Aerial Systems (UAS) have become a reference tool for agriculture applications. The integration of multispectral sensors that can capture near infrared (NIR) and red edge spectral reflectance allows the creation of vegetation indices, which are fundamental for crop monitoring process. In this study, we propose a methodology to analyze the vegetative state of almond crops using multi-temporal data acquired by a multispectral sensor accoupled to an Unmanned Aerial Vehicle (UAV). The methodology implemented allowed individual tree parameters extraction, such as number of trees, tree height, and tree crown area. This also allowed the acquisition of Normalized Difference Vegetation Index (NDVI) information for each tree. The multi-temporal data showed significant variations in the vegetative state of almond crops.
Long-term transport and storage of peeled almonds under unsuitable conditions may cause the product's rejection. To get knowledge in this topic, peeled almonds were stored at 25°C and 60, 70, and 80% relative humidity (RH). The maintenance of high RH (80%) caused some visual defects after 4 months. Even though the 60, 70, and 80% RH did not clearly affect the production of primary and secondary products formed in the lipid oxidation during the 6 months of storage, sometimes an increase in the values of the specific extinction at the wavelength of 268 nm (K268 ) was observed at 80% RH, suggesting the occurrence to some extent of secondary oxidation. Concerning microbial counts, the almonds stored at 60 and 70% RH presented a satisfactory microbial quality until 6 months; however, at 80% RH, the mold counts were higher than the reference values after 2 months. Several mycotoxins were detected at low levels, including aflatoxins B1 and G1, although some showed higher amounts at 80% RH. In general, it is recommended that almond producers and industrials should consider the use of low RH (< 80%) for maritime transport and long-term storage of almond kernels. PRACTICAL APPLICATION: High levels of relative humidity during storage/transport of almond kernels favor fungal growth, mycotoxin production, and secondary oxidation (rancidity). It is recommended to keep the almond kernels under low RH (< 80%) in maritime transport and long storage, especially in tropical countries.
The coffee berry borer, Hypothenemus hampei, is serious limitation in organic coffee production in Sao Tome Island in the Gulf of Guinea, limited information regarding this species seasonal phenology on the islands limits the implementation of biological control.In the present study, seven coffee plantations were monitored over two years to describe infestation patterns, penetration rates into coffee berries, and mortality by the entomopathogenic fungus,Beauveria bassiana in two coffea species (C. arabica L.and C. canephoraPierre ex A. Froehner), according to 30-tree sampling of fruits following the CENICAFE method. The results revealed that the borer position within the berries, infestation, and green berries with Beauveria bassianawere significantly affected by coffee variety. The infestation mean across all seven sites was (11.5±3.5% mean ± standard error (SE)), with two sites showing mean infestation <5%. The highest infestation and Beauveria bassianarates per branch monthly were observed in C. arabica L. (Red Caturra, Bourbon and Red Catuai), compared with C. canephoraPierre ex A. Froehner (Robusta) in the months of lower rainfall. Borer immature stages (eggs, larvae and pupae) and adults were found throughout the sampling period. No CBB predator and parasitoids were observed in the survey. The population level and developmental rate indicated that the coffee borer met favorable environmental conditions in the studied areas and control measures are required for reducing damage.
Introduction: The chestnut gall wasp, Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae), is a gall inducing insect original from China that attacks the Castanea genus and can significantly hinder production of chestnut trees. The most effective and used method of control of D. kuriphilus is based on the releases of Torymus sinensis Kamijo (Hymenoptera: Torymidae), a specific parasitoid of D. kuriphilus and native in its natural habitat of origin (China). Objectives: To evaluate T. sinensis ability to establish a population, its dispersion ability and the effect of the release density on the populations of D. kuriphilus in the Portuguese region of Minho. Methods: T. sinensis releases were made in three sites in the Barcelos and Viana do Castelo counties. Results: The presence of T. sinensis was found in three sites of release one year after the releases and in two sites two years after the releases. Presence of T. sinensis was also found at 200 meters distance from the release sites. Conclusion: The average parasitism rates found due to T. sinensis were between 1.3% and 3.9% in the first year, and 0.8% and 13% in the second year, which are within the range described in the international literature.
espanolIntroduccion: La avispilla del castano Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae) es un insecto inductor de agallas original de China que ataca al genero Castanea y puede causar perdidas significativas en la produccion de castanas. El metodo de biocontrol mas eficaz y utilizado se basa en las liberaciones de Torymus sinensis Kamijo (Hymenoptera: Torymidae), un parasitoide especifico de D. kuriphilus y nativo en su habitat original (China). Objetivo: Avaluar la capacidad de T. sinensis para establecer una poblacion, su capacidad de dispersion y el efecto de la densidad de liberacion en las poblaciones de D. kuriphilus en la region portuguesa del Minho. Metodos: Se realizaron tres liberaciones de T. sinensis en tres sitios de los condados de Barcelos y Viana do Castelo. Resultados: La presencia de T. sinensis se encontro en los tres sitios un ano despues de las sueltas y en dos sitios, dos anos despues de las sueltas. Tambien observamos la presencia de T. sinensis a 200 metros del punto de suelta, lo que revela su capacidad de dispersion. Conclusion: Las tasas de parasitismo estuvieron entre el 1.3% y el 3.9% en el primer ano, y entre el 0.8% y el 13% en el segundo ano, lo que esta en linea con lo mencionado en la bibliografia internacional. EnglishIntroduction: The chestnut gall wasp, Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae), is a gall inducing insect original from China that attacks the Castanea genus and can significantly hinder production of chestnut trees. The most effective and used method of control of D. kuriphilus is based on the releases of Torymus sinensis Kamijo (Hymenoptera: Torymidae), a specific parasitoid of D. kuriphilus and native in its natural habitat of origin (China). Objectives: To evaluate T. sinensis ability to establish a population, its dispersion ability and the effect of the release density on the populations of D. kuriphilus in the Portuguese region of Minho. Methods: T. sinensis releases were made in three sites in the Barcelos and Viana do Castelo counties. Results: The presence of T. sinensis was found in three sites of release one year after the releases and in two sites two years after the releases. Presence of T. sinensis was also found at 200 meters distance from the release sites. Conclusion: The average parasitism rates found due to T. sinensis were between 1.3% and 3.9% in the first year, and 0.8% and 13% in the second year, which are within the range described in the international literature. portuguesIntroducao: A vespa-das-galhas-do-castanheiro, Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae), e um inseto indutor de galhas originario da China que ataca especies do genero Castanea e que pode causar prejuizos significativos na producao de castanha. O metodo de controlo mais usado e eficaz e baseado em largadas de Torymus sinensis Kamijo (Hymenoptera: Torymidae), um parasitoide especifico de D. kuriphilus e autoctone no seu habitat de origem (China). Objetivo: Estudar a capacidade de T. sinensis estabelecer uma populacao, a sua capacidade de dispersao e o efeito da densidade de largada nas populacoes de D. kuriphilus existentes na regiao portuguesa do Minho. Metodos: Foram realizadas largadas de T. sinensis em tres locais distintos nos concelhos de Barcelos e Viana do Castelo. Resultados: Registou-se a presenca de T. sinensis nos tres locais um ano apos as largadas e em dois locais, dois anos apos as largadas. Observamos igualmente a presenca de T. sinensis a 200 metros do ponto de largada, o que revela a sua capacidade de dispersao. Conclusao: As taxas de parasitismo situaram-se entre 1.3% e 3.9% no primeiro ano, e 0.8% e 13% no segundo ano, valores concordantes com o referido na bibliografia internacional.
In recent years, the Asian gall wasp Dryocosmus kuriphilus has invaded chestnut trees and significantly affected the Portuguese chestnut production. Studies in other countries, such as Japan or Italy, have shown that the parasitoid Torymus sinensis can successfully achieve biological control of D. kuriphilus. Mathematical models help us to understand the dynamics of the interaction between the pest D. kuriphilus and its parasitoid T. sinensis and, consequently, they can help to implement measures that enhance crop pest management. In this work, the evolution of the density of D. kuriphilus and T. sinensis across time and space is studied through the numerical solution of models that include parameters based on observations made in Portugal. Simultaneous releases of the parasitoid are simulated at various locations and at different times. The results indicate that, in the case of a small and homogeneous orchard, biological control can be effective, but, in the case of extensive domains, the pest control is much more difficult to achieve. In order for biological control to be efficient, it is necessary to implement, in each chestnut-producing region, a collective strategy based on the annual monitoring of infestation levels.
Introdução: O castanheiro apresenta enorme importância económica, social, cultural e ambiental, em Trás-os-Montes (Portugal), constituindo-se ainda como um dos elementos caraterizadores da paisagem. O bichado-da-castanha, Cydia splendana (Hübner) é considerado praga-chave da cultura, afetando a qualidade e quantidade da castanha. Objetivos: O presente estudo teve como objetivo conhecer, de forma mais aprofundada, a biologia do bichado-da-castanha e a sua importância económica. Métodos: Em 2018 e 2019, em seis soutos da região de Trás-os-Montes, situados em Bragança (Samil, Espinhosela e Parâmio), Macedo de Cavaleiros (Amendoeira), Vinhais (Espinhoso) e Valpaços (Sobrado), localizados a diferentes altitudes e em diferentes condições climáticas, procedeu-se à monitorização da praga nas diferentes fases de desenvolvimento (estados imaturos e adultos) e à estimativa dos estragos provocados. Os adultos foram monitorizados recorrendo a armadilhas delta, com feromona sexual (três por souto), distanciadas entre si em 50 m e os estados imaturos através da colheita de 200 folhas e 100 ouriços/frutos, por souto. Em laboratório, registaram-se o número de ovos e larvas. A intensidade de ataque foi avaliada através da dissecação de 1800 frutos apanhados ao longo da colheita. Resultados: Foram registadas capturas do bichado-da-castanha, entre meados de agosto e início de outubro em 2018, com o pico do voo a ocorrer em finais de agosto, na maioria dos soutos. Em 2019 o período de voo foi mais curto, terminando em finais de setembro, com um pico de voo na segunda semana de setembro. Em 2018, as primeiras posturas observaram-se em meados de agosto e as primeiras larvas na última semana de agosto, em quanto em 2019 as posturas se iniciaram cerca de uma semana mais tarde. A intensidade de ataque dos frutos, situou-se entre os 10.0% no souto de Sobrado e os 23.3% no souto de Espinhoso. Conclusões: A biologia do inseto parece ser ligeiramente influenciada pelas condições climáticas do local. Os níveis de captura são superiores em Macedo de Cavaleiros (Amendoeira), situado a uma altitude 766 metros, num souto com coberto vegetal destrocado periodicamente. Os prejuízos causados por C. splendana, foram maiores em soutos onde na área envolvente existem soutos abandonados e/ou mata de castanheiros bravos, como é o caso do souto de Espinhoso com 23.3% e do souto de Samil com 16.0% de castanhas atacadas. As castanhas dos castinçais e soutos abandonados, normalmente não são apanhadas, contribuído assim para o aumento da população da praga.
a renewed interest in this species. The increase in the consumption of almonds worldwide has created conditions for prices to remain a little more attractive than in previous years, which, together with the general failure of the dryland arable sector (cereals in particular) in the inland of the country, has stimulated the appearance of new plantations of almond trees. The phenomenon is particularly relevant in Alentejo, associated to the new irrigation infrastructures, with intensive plantations, but also in Trás-os-Montes, where rainfed orchards prevail. The almond tree has been valued for the edible part of the nut and occasionally in winter tourist routes associated with flowering, as mentioned. However, several by-products of the almond tree can be valorized, especially those that present greater quantitative expression such as hull (2000 t year -1 ), shell (9000 t year -1 ), tegument (120 t year -1 ) and pruning wood (25000 t year -1 ). In this work, an estimate is made of the quantity of the by-products produced in Portugal and clues for their potential uses presented.
O conhecimento da artropodofauna das culturas (fitofagos, predadores, parasitoides e indiferentes) e das relacoes existentes entre si e fundamental numa perspetiva de conservacao da fauna auxiliar, de promocao da protecao biologica contra as principais pragas e de manutencao da cultura em bom estado fitossanitario. No caso da amendoeira, o conhecimento acerca da biologia das pragas-chave, a sua dinâmica populacional e os predadores e parasitoides associados e ainda escasso em Portugal. Assim, este trabalho teve por objetivo conhecer a riqueza e abundância dos artropodes associados ao amendoal e, em particular, os potenciais predadores e parasitoides. Nesse sentido, entre abril e inicio de outubro de 2018 e 2019, semanalmente, realizou-se a tecnica das pancadas em 25 arvores (2 ramos por arvore e duas batidas/ramo) selecionadas aleatoriamente num amendoal localizado em Alfandega da Fe. O material colhido foi separado e os artropodes existentes contados e identificados ao mais baixo nivel taxonomico possivel (ordem, familia, genero ou especie). Os resultados obtidos mostram a existencia de uma grande abundância e diversidade de artropodes. No que respeita aos auxiliares, por ordem de importância relativa e respetivamente em 2018 e 2019, surgiram as aranhas com 14% e 20%, os coccinelideos com 6,5% e 2,6%, os himenopteros parasitoides com 3,0% e 7,1% e os crisopideos com 0,6% e 1,8%. Os himenopteros parasitoides e os coccinelideos surgiram em maior numero no periodo de maio a julho, coincidente com a presenca de estados imaturos de diferentes pragas do amendoal, como os afideos, larvas de lepidopteros e monosteira.
Replacing artificial additives by natural compounds is a current trend in the food industry. In addition to their preserving effect, naturally obtained ingredients often exhibit important levels of bioactivities. Generally, plant species represent better sources of natural ingredients, since their compounds are less prone to causing unpleasant taste or odour. Chestnut male flower (CMF) was reported to have high antioxidant and antimicrobial activities. Hence, it was tested as an alternative to potassium sorbate in the most treasured Portuguese delicacy: "pastel de nata". Different nutritional, chemical, physical and bioactive parameters were compared in two different periods: baking day and two days after baking. All samples presented similar nutritional and chemical profiles, but those added with CMF revealed higher contents of reducing agents and radical scavengers. Accordingly, the newly obtained formulation is expected to have better effects on consumers' health, maintaining the chemical characteristics, besides rendering a novel, economically profitable, application to CMF.