Pest Consumption Research Articles

Nature-based solutions to increase rice yield: An experimental assessment of the role of birds and bats as agricultural pest suppressors in West Africa

Rice is widely consumed as a staple food, being cultivated worldwide. However, in West Africa, production is not enough to satisfy demand. Rice often suffers intensive damage by herbivorous arthropods that affect quality and quantity of the grain. Birds and bats have been shown to suppress arthropod pests, potentially enhancing rice productivity and food security. However, the degree to which these taxa provide nature-based solutions for mitigating pest-induced rice losses is poorly known, especially in West Africa. Here, we used experimental exclosures to investigate whether birds and bats reduce plant damage and boost rice yield by suppressing arthropod abundance. In a rural area in northern Guinea-Bissau, we established 14 sets of paired control and experimental exclosures parcels, precluding access of birds and bats to rice plants. We then quantified how the absence of birds and bats influenced arthropod communities, plant damage, and rice yield over a full rice production cycle (six months). Arthropod numbers in exclosures (10.1 ± 9.1 ind./plot) were nearly double those in control plots (5.8 ± 3.0 ind./plot), a result mostly due to a lower spider abundance in the controls. The percentage of leaf and grain damage showed no difference between exclosure and control. Using Structural Equation Models, we uncovered that the exclusion of birds and bats boosted arthropod abundance but had only marginal effects on rice damage and no detectable effect on yield. The exclusion of flying vertebrates led to a marked increase in spider abundance, suggesting an effect of mesopredator release, which in turn likely helped maintaining pest abundance low and potentially contributing to the small overall effect on rice damage and yield. Enhancing the abundance of birds and bats is an interesting option to suppress agricultural pests, but our results highlight the need for a better understanding of ecological interactions in agricultural landscapes in West Africa. We stress the need for more research to inform evidence-based policies using nature-based solutions that foster the natural consumption of pests by vertebrates, as a means to improve food security.

All-you-can-eat buffet: A spider-specialized bat species (Myotis emarginatus) turns into a pest fly eater around cattle.

Determining the dietary spectrum of European insectivorous bats over time is the cornerstone of their conservation, as it will aid our understanding of foraging behavior plasticity in response to plummeting insect populations. Despite the global decline in insects, a restricted number of arthropod pest species thrive. Yet past research has overlooked the potential of European bats to suppress pests harmful to woodlands or livestock, in spite of their economic relevance. Here we investigated the diet composition, its breeding season variations and pest consumption of an insectivorous bat species (Myotis emarginatus), at the northern edge of its range (Wallonia, Belgium). We also explored the prey ecology to gain insight into the hunting strategies and foraging habitats of this bat species. We used DNA metabarcoding to amplify two COI markers within 195 bat droppings collected in June, July and August, thereby identifying 512 prey taxa predominated by Diptera, Araneae and Lepidoptera. Overall, in 97% of the samples we detected at least one of the 58 potential pest taxa, 41 of which targeting trees. The June samples were marked by a diet rich in orb-weaver spiders, in accordance with the archetypal diet of M. emarginatus bats. However, during the highly energy demanding July-August parturition and lactation period, roughly 55% of the dropping samples contained two cattle fly pests (Stomoxys calcitrans and Musca domestica). Moreover, among the 88 Diptera species preyed upon by M. emarginatus in July and August, these flies accounted for around 50% of the taxa occurrences. This plasticity-the switch from a spider-rich to a fly-rich diet-seems providential considering the dramatic ongoing drop in insect populations but this involves ensuring bat-friendly cattle farming. Our results revealed that bats widely consume pest entomofauna, thereby highlighting their potential role as allies of forest managers and farmers.

The bat Tonatia bidens (Phyllostomidae) as an insect pest predator in the Brazilian Caatinga

Abstract Tonatia bidens is listed as ‘Data Deficient’ in the IUCN Red List. Our research, conducted in the Brazilian Caatinga dry forest between 2016 and 2022, aimed to shed light on the diet of this little-known species. Thirty-eight taxa were identified among insect remains beneath T. bidens’ feeding perch. Notably, certain insects such as hawkmoths and cerambycid beetles are agricultural pests with significant negative impacts on crops, including cassava, corn, tomato, papaya, and cashew plantations. These results underscore bats’ crucial role in insect pest consumption, emphasizing the need for further studies to fully understand their diet and ecosystem contributions.

The Consumption and Diversity Variation Responses of Agricultural Pests and Their Dietary Niche Differentiation in Insectivorous Bats.

Insectivorous bats are generalist predators and can flexibly respond to fluctuations in the distribution and abundance of insect prey. To better understand the effects of bats on arthropod pests, the types of pests eaten by bats and the response of bats to insect prey need to be determined. In this study, we performed DNA metabarcoding to examine prey composition and pest diversity in the diets of four insectivorous species of bats (Hipposideros armiger, Taphozous melanopogon, Aselliscus stoliczkanus, and Miniopterus fuliginosus). We evaluated the correlation between bat activity and insect resources and assessed dietary niche similarity and niche breadth among species and factors that influence prey consumption in bats. We found that the diets of these bats included arthropods from 23 orders and 200 families, dominated by Lepidoptera, Coleoptera, and Diptera. The proportion of agricultural pests in the diet of each of the four species of bats exceeded 40% and comprised 713 agricultural pests, including those that caused severe economic losses. Bats responded to the availability of insects. For example, a higher abundance of insects, especially Lepidoptera, and a higher insect diversity led to an increase in the duration of bat activity. In areas with more abundant insects, the number of bat passes also increased. The dietary composition, diversity, and niches differed among species and were particularly significant between H. armiger and T. melanopogon; the dietary niche width was the greatest in A. stoliczkanus and the narrowest in H. armiger. The diet of bats was correlated with their morphological and echolocation traits. Larger bats preyed more on insects in the order Coleoptera, whereas the proportion of bats consuming insects in the order Lepidoptera increased as the body size decreased. Bats that emitted echolocation calls with a high peak frequency and duration preyed more on insects in the order Mantodea. Our results suggest that dietary niche differentiation promotes the coexistence of different bat species and increases the ability of bats to consume insect prey and agricultural pests. Our findings provide greater insights into the role of bats that prey on agricultural pests and highlight the importance of combining bat conservation with integrated pest management.

Bat diversity boosts ecosystem services: Evidence from pine processionary moth predation

Coniferous forests contribute to the European economy; however, they have experienced a decline since the late 1990s due to an invasive pest known as the pine processionary moth, Thaumetopoea pityocampa. The impacts of this pest are increasingly exacerbated by climate change. Traditional control strategies involving pesticides have had negative effects on public health and the environment. Instead, forest managers seek a more ecological and sustainable approach to management that promotes the natural actions of pest control agents. This study aims to evaluate the role of bats in suppressing pine processionary moths in pine forests and examine how the bat community composition and abundance influence pest consumption. Bats were sampled in the mountainous environment of the Serra da Estrela in central Portugal to collect faecal samples for DNA meta-barcoding analysis. We assessed the relationship between a) bat richness, b) bat relative abundance, c) bat diet richness, and the frequency of pine processionary moth consumption. Our findings indicate that sites with the highest bat species richness and abundance exhibit the highest levels of pine processionary moth consumption. The intensity of pine processionary moth consumption is independent of insect diversity within the site. The highest occurrence of pine processionary moth presence in bat diets is primarily observed in species that forage in cluttered habitats. A typical predator of pine processionary moths among bats is likely to be a forest-dwelling species that specialises in consuming Lepidoptera. These species primarily use short-range echolocation calls, which are relatively inaudible to tympanate moths, suitable for locating prey in cluttered environments, employing a gleaning hunting strategy. Examples include species from the genera Plecotus, Myotis, and Rhinolophus. This study enhances our understanding of the potential pest consumption services provided by bats in pine forests. The insights gained from this research can inform integrated pest management practices in forestry.

Integrating local and ecological knowledge to assess the benefits of trees for ecosystem services: A holistic process-based methodology

Management decisions in agriculture regarding landscape structure, biodiversity conservation, food production, climate adaptation and other planetary issues need to be supported by sound data and innovative solutions. The food system can and must become a part of the solution, particularly if it integrates nature-based solutions promoting biodiversity as services, such as pest control provided by local birds. Birds have been shown to contribute to invertebrates’ predation and pest control, among many ecosystem services, in agricultural landscapes, especially where trees are present. Trees are also services providers and can contribute to ecosystem regulation, shelter and foraging of species, among other important contributions. In this study, we developed a methodology that integrates species, trait, and crop data; pest predation indicators and local farmers’ expertise, to determine the consumption of pests by birds, in intensive farming systems of Central Portugal. Our aim was to investigate the relationship between birds and service provision over a tree gradient, at the landscape level. For that, we used point count data to estimate the daily consumption of invertebrates by birds, based on energy requirements and life cycle characteristics of each species. Using species guilds, we related habitat requirements to pest control services, which showed higher predation in annual crops close to trees or woody vegetation compared to the ones with just crops. Further, we analysed the methodology’s main challenges and strengths. Lastly, we concluded that the holistic characteristic of the developed process would guide stakeholders and policy’ elaboration more effectively, as we have learnt that farmers’ participation enabled more accurate analysis and results and could bring them closer to the research process.

Tropical insectivorous birds’ predation patterns that promote forest–farmland trophic connectivity for integrated top–down pest biocontrol

Although conversion of natural forest to agriculture can negatively impact biodiversity in many ways, some affected species may respond by dispersing across the forest–farmland eco-zone, thereby facilitating functional connections through food-web interactions beneficial to crop production and forestry. This study examined patterns of Lepidoptera (butterflies and moths), Hemiptera (bugs), and Coleoptera (beetles) herbivory, and insectivorous bird predation within forest-adjacent farms in western Kenya, and how these processes trophically connect the two ecosystems to promote pest biocontrol. Through δ13C and δ15N stable isotope analyses, proportions of maize, farmland legumes and forest trees in pest diets, and pest-prey in bird’s diets were estimated. Birds’ habitat associations and diet specializations’ influence on pest consumption and basal plant carbon levels in birds’ tissues were determined to evaluate birds’ pest-biocontrol potential. Maize was the mostly consumed plant especially by Lepidoptera, but forest trees were peimarily consumed by Coleoptera and Hemiptera. In turn, Lepidoptera were mainly consumed by forest-associated birds, whereas Hemiptera and Coleoptera were mostly consumed by farmland-associated birds. Thus, birds showed cross-habitat pest consumption tendencies, though diet-specialization was unimportant in predicting those tendencies. Muscicapidae (flycatchers and allies); Hirundinidae (swifts and swallows); Motacillidae (pipits and wagtails); and Ploceidae (weavers) birds showed the highest contributory potential for pest biocontrol of Lepidoptera pests, but Estrildidae (manikins and waxbills), Muscicapidae, and Malaconotidae (boubous and gonoleks) birds showed the best potential against Hemiptera and Coleoptera. Furthermore, more maize basal carbon was assimilated by forest-associated compared to farmland-associated birds, whereas most basal carbon from farmland legumes and forest trees were assimilated by farmland birds, suggesting that unlike pest-prey choice, basal plant carbon pathways to avian insectivorous consumers did not strongly mirror birds’ habitat associations. Lepidoptera and Hemiptera were potentially the most significant interhabitat trophic connector arthropods, and for birds, Muscicapidae, Ploceidae, and Estrildidae. These findings show that such functional connectivity may be enhanced through increasing structural cover elements that promote insectivorous birds’ dispersal between farmland and adjacent forests to boost their pest-regulation ecosystem service contribution. The results serve to inform effective management practices by agronomists, foresters, and land-use planners toward promoting landscape-scale-integrated pest management for sustainable agriculture and biodiversity conservation.

Dynamics of a crop, pest and predator model in an agricultural system

A three-species model of the interactions of crop, pest, and predator has been constructed in this work. In the absence of pests and harvesting of crops, the rate of crop growth is considered as logistic. It is considered that pests consume crops whereas predators consume pests. Harvesting of the crops has been considered here. Holling type II functional response has been considered for crop and pest consumption. It is also assumed that the predators may consume pests via Holling type II functional response. Positivity and boundedness of the solution of the model have been investigated. The various equilibrium points of the model are evaluated, and the local and global stability are then investigated. Studies on the Hopf bifurcation existence criterion in connection to a crucial model parameter have been conducted. The optimal crop harvesting has then been determined using an objective function that has been defined. The Pontryagin’s maximum theory is used to calculate the ideal crop harvesting rate. The consumption of pests by predators has been proven to help keep the system stable up to a point, but a higher rate of pest consumption by predators can potentially cause instability. According to observation, the model may become unstable as the mortality rate of predators of pests rises. It is found that the increase in optimal harvesting of crops may lead the model towards stability. It has been noted that increased rate of crops consumption by pests may result in lower agricultural yields.

Fallow fields and hedgerows mediate enhanced arthropod predation and reduced herbivory on small scale intercropped maize farms – δ13C and δ15N stable isotope evidence

Fallow fields and hedgerows enhance agricultural landscape heterogeneity and boost predatory arthropod diversity, though there is little direct quantitative evidence of their value in mediating pest suppression. Here, stable isotope analyses were used to quantify the influence of fallow field presence, fallow size proportion of farms, hedgerow volume and hedgerow type, on arthropod pest consumption by six predatory taxa. Levels of herbivory by four arthropod taxa on three vegetation groups: maize, beans and non-crops – were also considered. This was achieved through mixing model analysis with δ13C and δ15N stable isotope to identify and estimate food-source proportions incorporated into tissues of arthropod consumers collected from ten maize farms intercropped with beans in western Kenya. Fallow fields’ presence supported predation on Lepidopteran herbivores by attracting predatory bugs and wasps, and mediated lower herbivory levels. Fallow size proportion corresponded to higher taxa-level predation by ants and spiders on phytophagous beetles, and overall increase in bean herbivory, but predicted no difference in maize or non-crop herbivory. Higher hedgerow volumes did not affect overall predation pressure, but supported increased bean herbivory by Lepidoptera, and lower maize consumption by Orthoptera. Exotic hedgerows supported highest wasp predation on Lepidoptera while spiders consumed significantly more Orthoptera and phytophagous beetle pests on indigenous-hedgerow farms. Similarly, exotic hedgerows corresponded to enhanced Lepidoptera bean herbivory while trophic linkage of maize and non-crops to pests overall, were stronger with indigenous hedgerows. Thus, in addition to thicker hedgerows, predatory spillover impacts of wasps, bugs and beetles can be enhanced with fallow presence and exotic hedgerows, and that of spiders and ants, with larger fallows. Overall, the choice, combination and application of farm habitat structural features to maximize predatory arthropods’ contributions to pest biocontrol requires knowledge of focal crops, dominant pest groups and their most important predators. The findings demonstrate that fallow fields and hedgerows are significant in supporting the biological component of integrated crop pest management.

Temperature fluctuation alters optimal predator community composition for anticipated biological control

Alongside pesticides and specialist predators, natural communities of generalist beetle and spider predators play an important role in suppressing agricultural pests. However, the predation pressure of natural communities can be unpredictable. Overall predation pressure is influenced by a dense network of potential intraguild interactions, which are further shaped by species traits and environmental factors. Understanding how these different influences combine to impact pest control is especially important in the context of changing global temperatures. Recent empirical studies have demonstrated that the foraging behavior of arthropod predators is influenced by an interaction between temperature and predator body size. To explore the consequences of these findings for intraguild interactions and pest control, we expand a previously published model describing interactions between arthropod predators and a pest population. The model assumed that interaction strengths are influenced by body size and habitat preference. In our updated model, we incorporate the effect of temperature on predator foraging activity. We parameterize the model to match empirically observed predator community composition in 10 agricultural fields and use simulations to demonstrate how temperature-dependent behaviors change the expected efficiency of the natural predator community. Then, we use an optimization approach to identify the most efficient composition of natural predators for pest control. We then evaluate whether the most efficient predator compositions would change with increasing average daily temperature and its variability, as is expected under future temperature change. We find that optimal communities often include predators with complementary foraging activity and that in 2 fields, the optimal community changes drastically under future temperatures. We also note that at some temperatures, foraging activity reduces the negative effects of intraguild interference on pest consumption. This work allows us to assess the effect of climate change on the efficiency of natural predator communities to control pest populations and provide guidance for farmers to design pest management strategies tailored to different climate scenarios.

Nest Boxes Increased Presence of American Kestrels in a Blueberry Production Region Despite Low Box Occupancy

ABSTRACT Landscape enhancements such as nest boxes can attract birds to agricultural areas, where they can provide ecosystem services such as pest reduction through their consumption of crop pests. However, there are large gaps in knowledge about how birds respond to enhancements. From 2014 to 2018 we installed American Kestrel (Falco sparverius; hereafter kestrel) nest boxes in a blueberry production region in western Michigan. From 2015 to 2018 we conducted surveys to monitor kestrel presence along 1.6-km transect segments (hereafter, sites) to estimate kestrel occupancy in areas with and without boxes. We also monitored box occupancy and reproductive success. Kestrel presence increased over time in the study area although there was some uncertainty in this trend. The presence of a box at a site did not increase kestrel presence there, but boxes in neighboring sites did increase presence. This indicated that enriching an area with boxes increases kestrel presence. Box occupancy rates were positively influenced by occupancy of the same box the previous year. Percent successful nests ranged from 75 to 100 percent, and mean number of fledglings produced was approximately 4 per nest box. Our results showed that nest boxes can serve as effective landscape enhancements to attract kestrels to agricultural landscapes, but the degree to which kestrels occupy boxes can vary geographically. Local-scale studies can provide information about the potential benefits and challenges of using nest boxes as a pest management tool.

TOXIC AND HARMFUL PLANTS OF NATURAL PASTURES OF ZHYTOMYR POLISSY

The main advantages of pasture keeping as one of the components of organic keeping of animals are revealed. Types of natural pastures of Zhytomyr Polissya of Ukraine and their productivity are described. The main types of harmful and poisonous plants for farm animals are given. Also described are the most common poisonings by various species of grazing plants, signs of poisoning, first aid and prevention. The effects of ruminants' consumption of certain pests and their effects on milk and meat quality have been described. The toxic effect of cultivated plants when eating them at different stages of the growing season is described. The component composition of the stands of the studied pastures has been established. The results of researches of natural pastures of different farms of Zhytomyr Polissya for the presence of poisonous plants and their species are given. A description of the toxic organs of plants, organs and systems of the affected animals is given. Recommendations on measures to control poisonous pasture plants have been developed and substantiated.

Bird predation and landscape context shape arthropod communities on broccoli

Abstract Birds increase crop yields via consumption of pests in some contexts but disrupt pest control via intraguild predation in others. Landscape complexity acts as an inconsistent mediator, sometimes increasing, decreasing, or not impacting pest control. Here, we examined how landscape context and seasonal variation mediate the impact of birds on arthropod pests and natural enemies, leaf damage, and yields of broccoli (Brassica oleracea) on highly diversified farms that spanned the USA west coast. Our study had two complementary components: a bird exclusion experiment and molecular diet analysis of 357 fecal samples collected from the most commonly captured bird species that also foraged in Brassica fields—American Goldfinch (Spinus tristis), American Robin (Turdus migratorius), Savannah Sparrow (Passerculus sandwichensis), Song Sparrow (Melospiza melodia), and White-crowned Sparrow (Zonotrichia leucophrys). Bird access yielded higher, rather than lower, numbers of pest aphids and increased their parasitism, while no other arthropods examined were consistently impacted. Independent of bird presence, percent natural cover in the landscape sometimes increased and sometimes decreased densities of arthropods in the mid-growth period, with diminishing impacts in the late-growth period. Herbivore feeding damage to broccoli leaves decreased with increasing amounts of natural land cover and in the late-growth period. Molecular diet analysis revealed that Brassica pests and predatory arthropods were relatively uncommon prey for birds. Landscape context did not alter the prey items found in bird diets. Altogether, our bird-exclusion experiment and molecular diet analysis suggested that birds have relatively modest impacts on the arthropods associated with broccoli plantings. More broadly, the limited support in our study for net natural pest control services suggests that financial incentives may be required to encourage the adoption of bird-friendly farming practices in certain cropping systems.

Roosting ecology of insectivorous bats in a tropical agricultural landscape

Abstract Bats spend more than half of their life in roosts, where key life events transpire. Therefore the availability and selection of roosts are important to bats everywhere, and may limit their ability to exploit every habitat, including agricultural landscapes such as paddy fields, orchards and tea plantations. This study aimed to investigate the day roosts used by insectivorous bat species in tea plantations of Sri Lanka. We surveyed 18 tea plantations where we recorded a total of 44 roosts involving five families and nine species of bats (Hipposideros galeritus, Hipposideros lankadiva, Hipposideros speoris, Rhinolophus beddomei, Rhinolophus rouxii, Megaderma spasma, Pipistrellus ceylonicus, Pipistrellus coromandra and Miniopterus cf. fuliginosus). Most (26) of the recorded roosts were geomorphic, (11) were anthropogenic, and (7) were in vegetation. H. lankadiva and M. cf. fuliginosus are the only species known to roost exclusively in geomorphic roosts; all others were opportunistic. Although protecting bat roosts is crucial for their conservation, it is challenging in view of existing tea management practices. Therefore, natural roosts should be maintained and protected. The introduction of artificial roosts might increase the number of bats able to forage over tea plantations and maximize their consumption of agricultural pests, thereby increasing tea production.

Going out for dinner-The consumption of agriculture pests by bats in urban areas.

Insectivorous bats provide ecosystem services in agricultural and urban landscapes by consuming arthropods that are considered pests. Bat species inhabiting cities are expected to consume insects associated with urban areas, such as mosquitoes, flying termites, moths, and beetles. We captured insectivorous bats in the Federal District of Brazil and used fecal DNA metabarcoding to investigate the arthropod consumed by five bat species living in colonies in city buildings, and ascertained whether their predation was related to ecosystem services. These insectivorous bat species were found to consume 83 morphospecies of arthropods and among these 41 were identified to species, most of which were agricultural pests. We propose that bats may roost in the city areas and forage in the nearby agricultural fields using their ability to fly over long distances. We also calculated the value of the pest suppression ecosystem service by the bats. By a conservative estimation, bats save US$ 94 per hectare of cornfields, accounting for an annual savings of US$ 390.6 million per harvest in Brazil. Our study confirms that, regardless of their roosting location, bats are essential for providing ecosystem services in the cities, with extensive impacts on crops and elsewhere, in addition to significant savings in the use of pesticides.

Using faecal metabarcoding to examine consumption of crop pests and beneficial arthropods in communities of generalist avian insectivores

Generalist insectivorous birds can provide ecosystem services in agricultural landscapes by consuming arthropod pests, or they can provide disservices when they consume beneficial arthropods. To examine bird impacts on arthropod communities, including pest control services, we need to know which arthropods birds commonly consume. Faecal metabarcoding is an emerging technique that can be used to identify prey from faecal samples, often to the species level. We used faecal metabarcoding to study diets of birds inhabiting the ecotone between soybean fields and adjacent grasslands in a largely agricultural landscape in Illinois, USA, during the summer of 2017. Whereas previous studies have used faecal metabarcoding to compare bird diets among species or among capture sites, we analysed samples from multiple species within a community at replicate sites. We collected and sequenced DNA from 132 faecal samples from 25 bird species captured at six sites. We found that birds consumed an extremely large and varied diet that differed among both species and sites, suggesting that birds were consuming prey opportunistically as available at each site. Of the nine most commonly detected prey species, three are known pests of soybeans. Bird diets also contained significantly more species of herbivorous prey than natural enemies. Finally, we discovered that American Goldfinches Spinus tristis, a highly granivorous species, may consume arthropods more frequently than expected and thus may provide ecosystem services in agricultural landscapes. Our study demonstrates that birds within this system consume a large variety of prey, suggesting that they may be able to respond quickly to pest outbreaks and contribute to agricultural resiliency.

Pest consumption by generalist arthropod predators increases with crop stage in both organic and conventional farms

AbstractBiocontrol agents are critical for pest management in sustainable agriculture. Generalist arthropod predators may hold a great potential as biocontrol agents because they are ubiquitous and consume pests in agroecosystems. However, their diet composition over the entire crop season has rarely been quantified, which hinders our ability to assess their biocontrol potential in real field conditions that foster temporal dynamics of pest and alternative prey populations. To fill this knowledge gap, we surveyed arthropod communities over crop stages in organic and conventional rice farms (n = 7 each) and used stable isotope analysis (δ13C and δ15N) to quantify the diet composition of generalist arthropod predators over time. We aimed to (1) examine the resource partitioning (trophic niches) in these predators, (2) quantify these predators’ diet composition from potential prey sources (rice herbivores, tourist herbivores, and detritivores), and (3) investigate the effects of farm type (organic/conventional) and crop stage (tillering/flowering/ripening stage) on pest (rice herbivore) consumption by the predators. The results show that generalist predators in both organic and conventional farms shifted trophic niches over the crop season and consumed a higher percentage of rice herbivores at late than at early crop stages (e.g., 90–93% at ripening vs. 34–55% at tillering), suggesting an increasing biocontrol value over time regardless of farm type. Surprisingly, generalist predators consumed higher proportions of rice herbivores in conventional than organic farms at tillering and flowering stages, highlighting their underappreciated potential as biocontrol agents in conventional farms. These results demonstrate that although generalist arthropod predators do consume non‐pest alternative prey, they have a high biocontrol potential (per capita pest consumption) in both organic and conventional rice farms. We encourage modern agriculture to develop techniques to support robust populations of these predators and the ecosystem services that they provide.

Winter cover crops shape early‐season predator communities and trophic interactions

AbstractDespite the dynamic nature of annual cropping systems, few studies have investigated how the structure of predator communities and their interactions with prey corresponds with crop seasonality. Adding winter habitat, such as cover crops, improves soil health and likely contributes seasonal habitat availability for arthropod communities. Stable habitat may lead to functionally diverse predatory communities and their associated ecosystem services, such as biological control. Here, we estimated predatory community functional changes based on foraging traits determined by molecular gut–content analysis (MGCA) in response to winter cover crops (rye and crimson clover) in a cotton agroecosystem. Predators were collected from replicated 1‐ha experimental field plots during each major stage of crop development in 2017 and 2018, and MGCA was used to estimate predator roles and responses to cover crop treatments. Cotton planted into a rye cover crop residue promoted unique predator communities in the early and mid‐season as compared to no‐cover fields. Correspondingly, we observed dissimilar prey consumption among cover crop treatments. Winter cover crops led to an increase in consumption of alternative prey and incidental pests by natural enemies on seedling cotton and encouraged high predator diversity that aligns temporally with potential early‐season pest outbreaks. Therefore, cover crops commonly employed for soil health and erosion benefits also contribute to pest management by providing habitat and alternative prey resources that boost early‐season predatory arthropod communities.

Consumption of insects by birds in guava orchards (Psidium guajava L.)

The consumption of insect pests by birds can result in benefits for the farmer. In this sense, the present study aimed to investigate the consumption of insects by wild birds within guava orchards in the upper Sertão Sergipe. The records were conducted from 15 to 30 November 2018, using the direct observation method. 98 feeding events were recorded for 21 bird species. Among the insects consumed by birds, we highlight the caterpillars and bedbugs of the genus Leptoglossus, considered insects harmful to guava. It is possible that birds can reduce the populations of these insects and help with pest control. However, we recommend that experimental studies be performed for confirmation. The results of this research can also be used to change farmers' perceptions of birds, who normally see birds only as animals harmful to crops.

Effect of irrigation level and nitrogen fertilizer on water consumption and faba bean growth

A field experiment was conducted in Babil governorate to find out the effect of water tightening with different irrigation levels and fertilization with different urea levels on water consumption of pests and some of its characteristics. Agricultural land was selected and prepared for cultivation and the field was divided. It was treated with three levels of irrigation, which are (30, 50, 70) % of the ready water, and three levels of urea, which are (0, 50, 100) kg urea.After the end of the experiment, the actual water consumption, the reference water consumption and the yield factor were calculated. The water consumption was (562, 482, 382) mm for each of the levels of irrigation (30, 50, 70)% of the prepared water, respectively.As for the characteristics of the plant, it was found that the best treatment that achieved good productive and vegetative characteristics is the treatment of depletion of 30% and the level of urea 100 kg, as the values reached (75.3, 83.2, 20, 5284) for each of the plant height, dry weight, number of branches and seed yield respectively.. The water stress reduces plant productivity due to water stress, as well as the high level of urea, which helped improve plant properties.