Search Results (18)

Agricultural facilities in tropical regions such as Hainan China face dual challenges from summer typhoons and occasional winter cold waves. Traditional greenhouses are generally constructed at a low height to resist typhoons, which hinders mechanized operations, while the use of insect-proof screens compromises thermal insulation. To resolve these contradictions, this study designs a typhoon-resistant multi-span greenhouse with an elevatable roof. Its core innovation lies in adopting a mechatronic steel cable system to achieve synchronized elevation of single-span roof surfaces. During daily operations, the roof is elevated to facilitate mechanized field operations; during typhoons or cold waves, the roof is lowered to the ground, reducing wind load impact and improving thermal insulation performance. The greenhouse’s elevating system incorporates multiple safety functions, including bidirectional self-locking and overload protection. Structural calculations using PKPM 2010 software show that under two working conditions—roof elevated (basic wind pressure of 0.45 kN/m²) and roof lowered (basic wind pressure of 1.30 kN/m²)—all indicators meet the requirements of relevant codes. Compared with an ordinary circular-arch greenhouse of the same size and under the same loads, the steel consumption of the standard single-span frame (6 m span, 4 m bay width) of the Elevating Greenhouse is only 67.38 kg, a 35% reduction compared with 103.58 kg for the ordinary greenhouse, significantly reducing construction costs. This study provides an innovative, safe, and economical technical solution for protected agriculture in tropical regions. Full article

Organismal biosensing leverages the olfactory acuity of living systems to detect volatile organic compounds (VOCs) associated with cancer, offering a low-cost and non-invasive complement to conventional diagnostics. Early studies demonstrate its feasibility across diverse platforms. In C. elegans, chemotaxis assays on urine samples achieved sensitivities of 87–96% and specificities of 90–95% in case–control cohorts (n up to 242), while calcium imaging of AWC neurons distinguished breast cancer urine with ~97% accuracy in a small pilot cohort (n ≈ 40). Trained canines have identified prostate cancer from urine with sensitivities of ~71% and specificities of 70–76% (n ≈ 50), and AI-augmented canine breath platforms have reported accuracies of ~94–95% across ~1400 participants. Insects such as locusts and honeybees enable ultrafast neural decoding of VOCs, achieving 82–100% classification accuracy within 250 ms in pilot studies (n ≈ 20–30). Collectively, these platforms validate the principle that organismal behavior and neural activity encode cancer-related VOC signatures. However, limitations remain, including small cohorts, methodological heterogeneity, and reliance on binary outputs. This review proposes a Dual-Pathway Framework, where Pathway 1 leverages validated indices (e.g., the Chemotaxis Index) for high-throughput screening, and Pathway 2 applies machine learning to high-dimensional behavioral vectors for cancer subtyping, staging, and monitoring. By integrating these approaches, organismal biosensing could evolve from proof-of-concept assays into clinically scalable precision diagnostics. Full article

Recent research has demonstrated a presence inside the seeds of several plant species of endophytic bacteria that can directly or indirectly interact with germination and seedling growth. Phytoplasmas are plant-pathogenic bacteria that severely impact the agricultural productivity of several crops, including alfalfa, a crucial forage crop in which seed transmission was reported. Therefore, understanding the transmission pathways of phytoplasmas is essential for developing effective control strategies. This study investigates the seed transmission of phytoplasmas in alfalfa using seeds collected in Oman in 2002 and kept in a dry environment in a laboratory for 20 years. The sterilized seeds were germinated and grown in agar medium under sterile conditions and transplanted in soil under greenhouse-controlled insect-proof conditions. Utilizing polymerase chain reaction (PCR) and nested PCR followed by RFLP and sequencing analyses, the alfalfa seedlings were screened for the phytoplasma presence. The detection of phytoplasmas in 16SrIII, 16SrV, 16SrX, and 16SrXII groups was achieved, confirming the preliminary results obtained in the 2002 testing of the same seed batches. This finding indicates that seed transmission could be a critical pathway for the spread of these pathogens in alfalfa, considering their survival in seeds for more than 20 years. Further investigations into the mechanisms of seed transmission and the development of resistant alfalfa varieties are essential to enhance the sustainability and productivity of alfalfa cultivation, thereby supporting the agricultural sector’s efforts to meet the growing demand for high-quality forages. Full article

Drosophila suzukii is an invasive pest that poses a significant threat to fruit crops worldwide, leading to considerable agricultural losses and economic damage. Unlike chemical control measures against D. suzukii, integrating insect-proof nets within an IPM framework offers a more sustainable solution. This study evaluates the efficacy of nine commercial protective nets against this pest, focusing on determining optimal hole dimensions based on the effects of airflow velocity, temperature, and pest morphometry on net performance. To simulate field conditions in the laboratory, we developed a tubular device divided into three chambers with the tested net placed between the two, incorporating a fan to generate airflow and a thermo-anemometer. Our results confirm that higher air velocities and elevated temperatures reduce net efficacy. Additionally, morphometric analyses of lab-reared flies revealed significant sexual dimorphism and a strong temperature–size relationship, with flies reared at lower temperatures being consistently larger, an aspect that also affects net effectiveness. These findings highlight the importance of considering both abiotic factors and pest morphology when evaluating protective screens, challenging the assumption that exclusion net efficacy remains constant. Some tested nets proved completely effective against SWD, supporting their use as a preventive measure in IPM programs. Full article

Due to human activities and changes in land use, the spatiotemporal pattern of citrus has undergone significant changes after the outbreak of Huanglongbing (HLB). We selected time-series Sentinel-2 images to delineate citrus orchard areas following the onset of HLB. This was conducted to extract citrus orchards in Xunwu County between 2017 and 2022. The spatial and temporal patterns and their influencing factors were investigated by spatial analysis. Results show (1) a notable decline in total citrus orchard area by 216.70 km², primarily witnessed in orchards without insect-proof screens (IPS), shifting towards cropland, bush, and IPS areas. Contrastingly, citrus orchards with IPS exhibited a modest increase from 7.82 km² to 111.39 km², predominantly converting from areas lacking IPS, cropland, and bare land. (2) Spatial distribution patterns revealing a “cold in the south and hot in the north” trend. Orchards without IPS are concentrated in central and northern regions, while those with IPS are clustered predominantly in the north, with a recent shift towards the northeast. (3) Landscape analysis indicating a trend of fragmentation of citrus orchards, while a gradual dispersion of orchards without IPS and those with IPS showcased enhanced concentration and aggregation. (4) Orchards with IPS predominantly occupy regions characterized by an elevation ranging between 300 m and 400 m, primarily in the southeast, southwest, and southern directions. These areas exhibit slopes averaging between 10° and 15°, with surface temperatures ranging from 18 °C to 26 °C. Additionally, these orchards tend to be situated in proximity to impervious surfaces and roads. Full article

Citrus is a crucial agricultural commodity of the hilly subtropical regions of southern China. Attempts in recent years to combat the destructive disease Huanglongbing (HLB) have led to citrus orchards being covered with insect-proof screens (IPS). Understanding which citrus orchards are covered by IPS is crucial for regional water and soil conservation, as well as control of plastic pollution. However, monitoring of orchards is complicated by IPS spectral interference in remotely sensed image classification. Here, an optimal feature combination scheme is developed and tested for mapping citrus orchards that use IPS. Seasonal Sentinel-2 images from 2021 were used to define indices for vegetation, plastic mulch, red edge, and texture. These were combined with topographic and land surface temperature using random forest classification to determine optimal feature discrimination combinations for orchards in Xunwu County, Jiangxi Province. Results show: (1) significantly higher visible light reflectance from IPS orchards ensures spectral discrimination between IPS covered and uncovered orchards. (2) After feature optimization, the seasonal spectral band has the highest accuracy (86%) in single feature classification. The addition of conventional indices and topographic-temperature features improves classification to 92%. (3) Xunwu County had 460 km² of citrus orchard cover in 2021, with 88 km² (19%) of that total being covered with IPS. Our method effectively and accurately maps citrus orchards with or without IPS coverage at 10 m resolution. The effective monitoring of large-scale IPS in other regions can now support the development of local and regional sustainable agricultural policies. Full article

Insect-proof screens are a physical method of crop protection against pests whose use is widespread. The hole size must be optimized since too small holes give rise to poorly porous textiles that cause a significant reduction in the permeability of the textiles to air. A common design strategy is to use a rectangular-hole geometry with the aim of limiting the hole width to prevent insect entry and increasing the hole length to increase the hole surface. However, the validity of this approach has not been tested, and indications suggest that it may not be offering the expected results. The results obtained discredit this widely accepted design criterion since they show that, while the hole width is maintained, protective screens lose efficacy as the hole length increases at least in the range of values considered. It is not possible to find an explanation for these results by considering the hole geometry from a two-dimensional point of view. However, when considering the spatial arrangement of the threads, it is understood that the passage surface for the insects is larger than that considered in the orthogonal projection images and that as the hole length increases, the efficacy of the textiles decreases. Full article

Permeability and inertial factor are the most relevant variables in the Forchheimer equation. They are important to estimate pressure drop when a fluid flow is passing through a porous media. However, in the insect-proof screens field, the existing models to date are still providing a poor predictive accuracy, in part due to they are based on 2D porosity of screens. This work provides novel models for permeability and inertial factor, which are developed from experimental data of insect-proof screens in a wind tunnel and the analytical estimation of 3D porosity. Instead of fitting models directly on observed training data values of permeability and inertial factor, we propose to focus the modelling efforts on finding models dependent on the 3D porosity through the constants in the pressure drop of Forchheimer equation. Since two screens can have the same 2D porosity but different 3D porosity, this makes also models more reliable. The combination of all these aspects has led to parametric models that overcome by far predictions by previous models in the literature. Full article

Despite the steadily increasing area under protected agriculture there is a current lack of knowledge about the effects of the insect-proof screen (IPS) on microclimate and crop water requirements in arid and semi-arid regions. Field experiments were conducted in two crop cycles in Ningxia of Northwest China to study the impact of IPS on microclimate, reference evapotranspiration (ET₀) and growth of Chinese Flowering Cabbage (CFC). The results showed that IPS could appreciably improve the microclimate of the CFC field in the two crop cycles. During the first crop cycle (C1), compared with no insect-proof screen (NIPS) treatment, the total solar radiation and daily wind speed under the IPS treatment were reduced by 5.73% and 88.73%. IPS increased the daily average air humidity, air, and soil temperature during C1 by 11.84%, 15.11% and 10.37%, respectively. Furthermore, the total solar radiation and daily wind speed under the IPS treatment during the second crop cycle (C2) were markedly decreased by 20.45% and 95.73%, respectively. During C2, the daily average air temperature and air humidity under the IPS treatment were increased slightly, whereas the daily average soil temperature was decreased by 4.84%. Compared with NIPS treatment, the ET₀ under the IPS treatment during C1 and C2 was decreased by 6.52% and 21.20%, respectively, suggesting it had great water-saving potential when using IPS. The plant height, leaf number and leaf circumference of CFC under the IPS treatment were higher than those under the NIPS treatment. The yield under the IPS treatment was significantly increased by 36.00% and 108.92% in C1 and C2, respectively. Moreover, irrigation water use efficiency (IWUE) was significantly improved under the IPS treatment in the two crop cycles. Therefore, it is concluded that IPS can improve microclimate, reduce ET₀, and increase crop yield and IWUE in arid and semi-arid areas of Northwest China. Full article

Dryocosmus kuriphilus Yasumatsu is a species originating from China that, during the 20th century, has spread rapidly throughout many countries, affecting mainly different species of the genus Castanea spp. In fact, it is considered to be the most important pest of chestnut trees (Castanea sativa Miller), causing significant production losses. The adoption of complementary measures to chemical and biological controls would contribute to the control of the pest. In this sense, the use of textile physical barriers could prevent the rapid spread of this species among the production centers. Therefore, the objective of this study is to define the characteristics of a textile that protects young plants that have been produced in nurseries. For this purpose, some commercial textiles have been selected based on the morphometric characterization of the species and these textiles have been accurately measured in order to compare their dimensions with those of the insects. Finally, tests have been carried out in order to measure the efficacy of the textiles under laboratory conditions, controlling the air velocity and the temperature. The results reveal that, in general, theoretical efficacy may not be a good predictor of practical results. A fully effective screen has been found against this species and its design characteristics can be used as a starting point for new, more optimized designs. Full article

Insect-proof screens are a frequent passive method to restrict the entrance of insects into greenhouses. However, the installation of these screens also has a negative effect on natural ventilation, which is reflected in the turbulence and velocity of the airflow inside the greenhouse. The turbulent characteristics of airflow through an insect-proof screen installed in the greenhouse windows have not been studied thoroughly in the literature. The present work focuses on the use of two simultaneous 3D sonic anemometers to study the impact of the use of a 13 × 30 threads·cm⁻² insect-proof screen on the turbulence properties of the micro and microscale airflow turbulence. Four tests have been carried out in windward-oriented side windows of a Mediterranean greenhouse. Results demonstrate that the approach of using two simultaneous 3D sonic anemometers for the first time allows one to observe that the effect is different for the three components of the velocity vector field, and there is a strong connection between the simultaneous conditions inside and outside of the greenhouse. Useful information and data on the effect of using a 13 × 30 threads·cm⁻² insect-proof screen are also provided. To give details on the impact of screens in the turbulent properties of ventilation is essential for any commercial distribution, as well as providing important data in the design and development of more efficient insect-proof screens. Full article

The growing interest in healthy foods has driven the agricultural sector towards eco-friendly implementation to manage biotic and abiotic factors in protected environments. In this perspective, anti-insect nets are an effective tool for controlling harmful insect populations concomitantly with reducing chemicals’ interference. However, the low porosity of nets necessary to ensure high exclusion efficiency for a designated insect leads to reduced airflow, impacting the productivity and quality attributes of vegetables. The evidence presented in this dataset pertains to the content of total nitrogen, minerals (i.e., NO₃, K, PO₄, SO₄, Ca, Mg, Cl, and Na), and organic acids (i.e., malate and citrate) of zucchini squash (Cucurbita pepo L. cv. Zufolo F1) in leaves and fruits grown with two anti-insect nets with different porosities (Biorete^® 50 mesh and Biorete^® 50 mesh AirPlus), is and analyzed by the Kjeldahl method and ion chromatography (ICS3000), respectively. Data of total nitrogen concentration, macronutrients, and organic acids provide in-depth information about plants’ physiological response to microclimate changes induced by anti-insect nets. Full article

The discovery of new insecticides improves integrated pest management (IPM), but is usually a long high-risk process with a low probability of success. For over two decades, insect neuropeptides (NPs) and their G-protein coupled receptors (GPCRs) have been considered as biological targets for insect pest control, because they are involved in almost all physiological processes associated with insect life stages. A key roadblock to success has been the question of how large volume chemical libraries can be efficiently screened for active compounds. New genomic and proteomic tools have advanced and facilitated the development of new approaches to insecticide discovery. In this study, we report a novel GPCR-based screening technology that uses millions of short peptides randomly generated by bacteriophages, and a method using an insect Sf9 cell expression system. The fire ant is a good model system, since bioactive peptides have been identified for a specific GPCR. The novel small peptides could interfere with the target GPCR-ligand functions. Therefore, we refer to this new mechanism as “receptor interference” (RECEPTORi). The GPCR-based bioactive peptide screening method offers multiple advantages. Libraries of phage-displayed peptides (~10⁹ peptides) are inexpensive. An insect cell-based screening system rapidly leads to target specific GPCR agonists or antagonists in weeks. Delivery of bioactive peptides to target pests can be flexible, such as topical, ingestion, and plant-incorporated protectants. A variety of GPCR targets are available, thus minimizing the development of potential insecticide resistance. This report provides the first proof-of-concept for the development of novel arthropod pest management strategies using neuropeptides, and GPCRs. Full article

Environmental pressure poses a major challenge to the agricultural sector, which requires the development of cultivation techniques that can effectively reduce the impact of abiotic stress affecting crop yield and quality (e.g., thermal stress, wind, and hail) and of biotic factors, such as insect pests. The increased consumer interest in premium-quality vegetables requires the implementation of sustainable integrated pest management (IPM) strategies towards an ever-increasing insect pressure, also boosted by cultivation under protected structures. In this respect, insect nets represent an excellent, eco-friendly solution. This review aims to provide an integrative investigation of the effects of the insect screens in agriculture. Attention is dedicated to the impact on growth, yield, and quality of vegetables, focusing on the physiological and biochemical mechanisms of response to heat stress induced by insect screens. The performance of insect nets depends on many factors—foremost, on the screen mesh, with finer mesh being more effective as a barrier. However, finer mesh nets impose high-pressure drops and restrict airflow by reducing ventilation, which can result in a detrimental effect on crop growth and yield due to high temperatures. The predicted outcomes are wide ranging, because heat stress can impact (i) plant morpho-physiological attributes; (ii) biochemical and molecular properties through changes in the primary and secondary metabolisms; (iii) enzymatic activity, chloroplast proteins, and photosynthetic and respiratory processes; (iv) flowering and fruit settings; (v) the accumulation of reactive oxygen species (ROSs); and (vi) the biosynthesis of secondary biomolecules endowed with antioxidant capacity. Full article

In a global climate change environment, assuring optimal growing conditions is a difficult challenge, compromising the food supply for a rapidly rising population. The climatic conditions in the protected environment lead to high temperatures and fast insect development, impacting productivity and vegetables qualitative attributes. Consumers’ interest in healthy food requires sustainable tools to manage biotic and abiotic factors and, from this perspective, anti-insect nets represent an excellent “green” solution. For this purpose, our goal was to compare two different anti-insect nets on microclimate, production, and qualitative traits of Cucurbita pepo L. fresh fruits. The experiment was conducted in three separate polyethylene high tunnels, with 50 mesh anti-insect nets of different porosities being installed on the openings of two tunnels, while the third tunnel was a control without nets. Microclimate measurements, as well as yield, physiological, and phytochemicals variables, were assessed. The 50 mesh net led to a decrease in marketable yield (22.5%), fruit number (18.0%), CO₂ net assimilation rate (6.0%), and transpiration rate (29.5%). Total soluble solids, antioxidant activities and total ascorbic acid concentration had an opposite trend. The 50 mesh AirPlus net improved quality aspects of zucchini fruits by increasing total ascorbic acid, total phenols, and antioxidant compounds, with no negative impact on yield. Full article