Diversity Of Flower-visiting Insects Research Articles

Taxonomic and Functional Diversity of Flower-Visiting Insects in Coffee Crops.

Despite the important role that flower-visiting insects play in agricultural production, none of the previous studies of coffee pollinators in Colombia have incorporated functional diversity into their analysis. Therefore, this study aimed to quantify the abundance, richness, and functional diversity of insects that visit flowers in coffee crops. Twenty-eight plots were selected among five sites in the north, center, and south of Colombia. In each plot, coffee flower insect visitors were collected and recorded on 90 trees at eight-minute intervals per tree, at three different times over three days. All sampling was carried out during two flowering events per year, over three years, resulting in a total of 1240 h of observations. Subsequently, the insects were taxonomically identified, and the number of individuals and species, as well as the diversity of the order q, were estimated. Functional diversity was also characterized in the bee community. The results: (a) 23,735 individuals belonging to 566 species were recorded; of them, 90 were bees, with the native species being the most abundant during 10:30 and 13:00 h; (b) bees formed five functional groups, with corbiculate and long-tongued non-corbiculate bees being the most abundant and occupying the largest regions of functional space; (c) potential pollinators in coffee crops are Apis mellifera, Nannotrigona gaboi, Tetragonisca angustula, Geotrigona cf. tellurica, and Partamona cf. peckolti. Coffee crops host a wide diversity of flower visitors, especially bees, which could be beneficial for productivity and contribute to the maintenance of plant species that accompany coffee cultivation.

A study of abundance and diversity of flower-visiting insects on marigold (Tagetes erecta L.) and sunflower (Helianthus annuus L.) at Rajshahi University Campus, Rajshahi, Bangladesh

A study of abundance and diversity of flower-visiting insects on marigold (Tagetes erecta L.) and sunflower (Helianthus annuus L.) at Rajshahi University Campus, Rajshahi, Bangladesh

A Systematic review of flower-visiting insect community research on agricultural crops in Indonesia

Evolutionary forces have developed many types of insect-plant interactions over millennia, ranging from herbivory, which causes damage, to mutualism between plant pollinators. Pollinators are a very important part of the natural history of plant evolution. Plants have evolved distinguished characteristics of flowers that attract many types of insects. Other than pollinators, flower-visiting insects also consist of various insect groups. The aim of this research was to assess the breadth and depths of research on flower-visiting insects. The research was conducted using secondary data derived from various databases for the past 20 years that were accessed and searched with keywords related to flower-visiting insects. Overall, 135 articles were screened from various databases. Over 42% of research was done by focusing on the diversity of flower-visiting insects, while 19% focused on effectiveness toward productivity, 14% on the landscape, and the rest focused on behavior, pesticide, etc. Fifty-two percent of the research was mostly done on horticultural crops such as tomatoes and cucumbers, while 44% was done on plantation plants-mostly dominated by oil palm research. From the biodiversity aspect, there were 8 orders of flower-visiting insects consisting of 54 families, 186 genera, and 186 species of insects. The flower-visiting insects that were found mostly belong to Hymenoptera and Lepidoptera. Over 50% of flower-visiting insects are pollinators, while the rest are herbivores, predators, and parasitoids. Forty-eight percent of the pollinators studied are hymenopterans. Our results also found that 35 genera of pollinators are identified as generalist pollinators, while 3 genera are specialist pollinators, such as Elaeidobius (oil palm), Forcipomyia (cocoa), and Nodocnemis (snake fruit). Data analysis showed that pollinators are positively correlated with productivity and quality of crops. Increase in productivity due to pollinators range from 27% in coffee to 1900% in zucchini.

If You Grow It, They Will Come: Ornamental Plants Impact the Abundance and Diversity of Pollinators and Other Flower-Visiting Insects in Gardens

Gardening for pollinators and other flower-visiting insects, where ornamental landscaping plants are added to provide habitats and foraging resources, may provide substantial benefits to declining insect populations. However, plant recommendations often lack empirical grounding or are limited geographically. Here, we created a pollinator garden, replicated across two sites, that contained 25 ornamental landscape plants that were either native or non-native to mid-Atlantic states and perennial or annual. Our objective was to determine the plants that would bring insect abundance and diversity to gardens. We surveyed the number and taxonomy of insects visiting the plants for two summers. We found a significant effect of plant species on both the abundance and diversity of flower-visiting insects. Insects were 42 times more abundant on our most visited plant (black-eyed Susan, Rudbeckia fulgida) versus our least visited plant (petunia, Petunia sp.). There was more than one diversity point difference in the Shannon index between the plant with the most (purple coneflower, Echinacea purpurea) and least (verbena, Verbena bonariensis) diverse visitors. Across our plants, honey bee (Apis mellifera) abundance positively correlated with other insect pollinators, although not specifically with wild bee abundance. Native perennials outperformed non-native perennials and non-native annuals in insect abundance, and both non-native and native perennials attracted more diversity than non-native annuals. Across plants, diversity scores quadratically related to insect abundance, where the highest diversity was seen on the plants with medium abundance. Lastly, we present the weighted sums of all insect visitors per plant, which will allow future gardeners to make informed landscaping decisions. Overall, we have shown that gardening schemes could benefit from a data-driven approach to better support abundant and diverse insect populations within ornamental landscape gardens.

Small floral patches are resistant reservoirs of wild floral visitor insects and the pollination service in agricultural landscapes

Small floral patches that coexist with crops in agricultural landscapes can function as biodiversity reservoirs. However, the influence of the landscape context and agricultural management on the capacity of these small green infrastructures to support diversity is poorly understood. Here, we evaluate the effect of landscape simplification, agricultural intensification in the neighbourhood, and quality of the floral habitats on the success of these patches to support flower-visiting insect communities as well as the pollination service they provide.To this aim, we sampled floral patches located in 18 paired olive farms with contrasting herb cover management (intensive vs. low-intensity), distributed along a wide gradient of landscape complexity at the regional scale of South Spain. We conducted surveys of flower-visiting insects in 36 multi-floral stands and 36 mono-floral stands of Sinapis alba Linnaeus (1753) within these floral patches. Mono-floral stands were used to evaluate variations in the pollination service through number of viable seeds and seed set.Results revealed that the abundance and diversity of flower-visiting insects respond to the quality of the floral patch (diversity of flowers) but not to landscape context nor agricultural management around it. Moreover, the pollination service was similar and high (seed set ca. 100 %) in all floral patches regardless of their context.Our findings highlight the importance of even small floral patches that function as reservoirs of diversity of flower-visiting insects and the pollination service. They also show the high resistance of these patches to agricultural intensification and simplification in olive grove landscapes.

Flower-visiting insects to Coffea arabica flower at different temperatures and the production of the fruit of arabica coffee

Temperature change may affect insect activity, including flower-visiting insects. Flower-visiting insects, particularly pollinators, have an impact on the fruits produced. This research aimed to study the relationships of flower-visiting insects at different temperatures and coffee production. The gauze experiment was carried out on the coffee plantation that consists of two sites, shaded and unshaded. The study involved 30 arabica inflorescences. The number of flower-visiting insects was recorded and captured. The results showed that the diversity of flower-visiting insects was related to the temperature differences. The flower-visiting insect on the unshaded site was more diverse than the shaded site. The formation of peaberries and the productivity of coffee fruit were also different. Peaberry production was lower (6.24 %) while the fruit mass was heavier (0.15±0.096 g/cherry) in unshaded than shaded sites. However, at the unshaded, the percentage of coffee beans defect was 0.56 % greater than the shaded one. According to these findings, more flower-visiting insects lead to the lower peaberry formation, the heavier fruit mass but potentially causing higher defective coffee beans. The increase in temperature due to climate change can be detrimental because these phenomena will increase the number of coffee fruit defects and insect pests.

Powerline right-of-way management and flower-visiting insects: How vegetation management can promote pollinator diversity.

Loss in the availability of early successional habitat is a threat to pollinator populations. Given that powerline rights-of-way (ROW) must be managed to maintain early successional habitat, preventing vegetation from interfering with electrical lines, they have the potential to provide conservation benefits for wild pollinators. Moreover, it is possible to provide conservation benefits with no additional cost to land managers. We surveyed flower-visiting insects over two years in different vegetation management treatments in a long-term research ROW to determine which best promoted pollinator abundance and species richness. We found that the ROW had stabilized in an early successional state soon after its establishment and that this early successional state could be maintained with low levels of periodic maintenance. We collected a high diversity of flower-visiting insects (126 bee species and 179 non-bee morphospecies) in six ROW plots. Higher levels of herbicide application had a negative effect on bee species richness, but low levels of herbicide application were compatible with a high abundance and species richness of flower-visiting insects, including several rare species. Moreover, this effect was seen only in the bee community, and not in non-bee flower-visiting insects. Our results suggest further research into the conservation value of ROW for pollinators is warranted. We demonstrate that there is substantial potential for pollinator conservation in ROW, compatible with low-cost vegetation management.

Higher richness and abundance of flower-visiting insects close to natural vegetation provide contrasting effects on mustard yields

The conservation of pollinating insects in agriculture is a global concern since the diversity of such organisms may affect the productivity of pollination-dependent crops. In this study, we assessed (i) how distances from natural vegetation affect the diversity (guilds, richness, abundance) of flower-visiting insects within mustard crops in Nepal, (ii) how insect richness and abundance are related to mustard yields (weight of seeds) and (iii) the contribution of flower-visiting insects to mustard pollination by conducting pollinator exclusion experiments. To analyse these data, we carried out (i) hierarchical clustering followed by a Procrustes analysis as well as a generalized linear mixed model and (ii), (iii) linear mixed models. We found that the guild composition was not similar near and far from natural vegetation, indicating a tendency for Apis bees to displace in opposite directions relative to non-Apis bees. Nevertheless, while both richness and abundance were higher nearer natural vegetation, the former showed a stronger and more positive effect on mustard yields than the latter. Furthermore, we found that mustard flowers have a significant requirement for insect pollination since productivity increased by ~70% with insect visitation. Overall, our data suggest that the diversity of flower-visiting insects enlarges nearer to natural vegetation. However, the results indicate that species richness may be more relevant than abundance to mustard production. As such, we suggest that the maintenance of natural vegetation could be considered a strategy for ensuring the presence of multiple pollinator species within mustard fields to promote its long-term sustainability in Nepal.

Impact of hiking trails on the diversity of flower-visiting insects in Wadi Telah, St. Katherine protectorate, Egypt

BackgroundA hiking trail is one of the major recreational activities that have critical impacts on wildlife. Wadi Telah in Saint Katherine Protectorate (South Sinai, Egypt) (N 28.568539 and E 33.932816) is an important spot for biodiversity. It was surveyed for spatial variation in the diversity of flower-visiting insects at different distances from the hiking trail. The current study aimed at assessing the impact of some anthropogenic activities along the main hiking trail passing through W. Telah on the diversity of flower-visiting insects. Field monitoring of flower visitors across the hiking trail passing through W. Telah was carried out at different distances (~ 0, 20, 40, and 60 m) along both sides of the hiking trail. As a control, monitoring was performed at 120 m from the hiking trail.ResultsA total of 542 individuals belonging to 34 species of flower visitors, 16 families, from three orders were recorded within the study localities in W. Telah. Floral resources in Wadi Telah can be a limiting factor for the populations of flower visitors. There was a significant difference in the distribution of the flower visitors’ species richness among different distances from the hiking trail in W. Telah. Species richness and abundance of flower visitors and their associated floral resources were significantly positively correlated to the distance from the hiking trail. There were no significant differences in the diversity of flower-visiting insects among different distances from the trail, perhaps due to their mobility.ConclusionsThe present study showed that the hiking trail had a negative impact on flower visitors and their associated floral resources in Wadi Telah. The investigation on how different biodiversity elements respond to hiking trails allows greater insight for protectorate managers. The study can contribute to effective management decisions for current and future protectorates.

Mustard plants distant from forest fragments receive a lower diversity of flower-visiting insects

Mustard fields (Brassica campestris: Brassicaceae) are mass flowering crops attracting a wide diversity of flower-visiting insects. Many studies have shown that the diversity of insects is higher near forest fragments than farther away from the forest edge and that Apis-bees numerically dominate such ecosystems. In this study, we investigated how insect diversity changes with distance from the forest edge (100 m, 1100 m, 2100 m) in mustard crop fields in Nepal. The effects of distance on both the abundance and richness of insects were evaluated using generalized linear mixed models, while Hill numbers were used to describe species diversity. We performed ordination analysis and PERMANOVA to examine the dissimilarity between insect communities at different distances. Finally, percent similarity was used to describe which insect species contributed most to the dissimilarity among distances. Our findings suggest that richness and abundance of the flower-visiting insects differed between distances of 100 m and 2.1 km from forest fragments. We found that values of all diversity measures were higher nearer to the forest fragments and moderately distant from the fragments. Accordingly, the ordination analysis corroborated the GLMMs, showing that insect community composition near to and moderately far from the forest fragments differed from that farther in the field. Additionally, we detected that solitary bee species (Andrena spp., Halictus spp. and Megachile lanata) outnumbered Apis-bees, greatly contributing to community discrimination among distances. Overall, we demonstrated that insect diversity within mustard crops is not homogeneous in Nepal. Cultivated plants farther from forest fragments are facing a deficit of diversity of flower-visiting insects. Furthermore, the role and the nesting habitat of solitary bees sampled here should be investigated, as they may contribute to mustard pollination in Nepal.

Quantifying the attractiveness of garden flowers for pollinators

There is great interest in planting urban areas to benefit pollinating insects, with the potential that urban areas and gardens could act as an extensive network of pollinator-friendly habitats. However, there are a great many different plant cultivars available to the gardener, and a paucity of evidence-based advice as to which plants are truly most attractive to flower-visiting insects. Here, we report insect visitation to metre square plots of 111 different ornamental plant cultivars at a site in central UK. Data were collected over 5 years, and comprise over 9000 insect observations, which were identified to species (for honeybees and bumblebees) or as ‘solitary bees’, Syrphidae, Lepidoptera and ‘others’. Unlike some previous studies, we found no difference in numbers of insects attracted to native or non-native species, or according to whether plants were annuals, biennials or perennials, but we did find that native plants attracted a significantly higher diversity of flower-visiting insects. Overall, the most-visited plants were Calamintha nepeta, Helenium autumnale and Geranium rozanne. However, patterns of visitation were quite different for every insect taxa examined. For example, different species of short-tongued bumblebees showed little overlap in their most-preferred plant cultivars. Interestingly, very similar plant cultivars often attracted different insect communities; for example, 72% of visitors to Aster novi belgii were honeybees or bumblebees, while the related Anthemis tinctoria, which also has daisy-like flowers, did not attract a single honeybee or bumblebee but was popular with solitary bees, hoverflies, and ‘other’ pollinators. Some plant cultivars such as Eryngium planum and Myosotis arvensis were attractive to a broad range of insects, while others attracted only a few species but sometimes in large numbers, such as Veronicastrum virginicum and Helenium autumnale which were both visited predominantly by honey bees. It is clear that we do not yet fully understand what factors drive insect flower preferences. Recommendations are made as to which flower cultivars could be combined to provide forage for a diversity of pollinator groups over the season from early spring to autumn, though it must be born in mind that some plants are likely to perform differently when grown in different environmental conditions.

Effects of natural pyrethrum and synthetic pyrethroids on the tiger mosquito, Aedes albopictus (skuse) and non-target flower-visiting insects in urban green areas of Padua, Italy

The tiger mosquito is a key vector of several human diseases and is considered a public health concern worldwide. The implementation of strategies aimed at maximizing mosquito control without affecting non-target insect groups is of major importance. In a field trial, we tested the efficiency of a natural pyrethrum-based vs. a synthetic pyrethroid-based insecticide in reducing tiger mosquito population and how they affect the diversity of non-target flower-visiting insects in green urban areas. Only the pyrethroid insecticide was effective in reducing mosquito abundance, although its effects disappeared nine days after application. The two adulticides did not significantly affect the diversity of flower-visiting insects, probably because of their large body size and the difference in flying and foraging activity. To effectively control mosquito populations while preventing intoxication of non-target flower-visiting insects, adulticide applications should be applied early in the morning and only on bushes and trees. Results from our small-scale applications cannot be extrapolate when larger areas are treated.

Keanekaragaman serangga pengunjung bunga pada tanaman tumpang sari kedelai dengan tanaman orok-orok (Crotalaria juncea)

Tumbuhan berbunga dapat meningkatkan populasi serangga polinator, yang sekaligus berperan penting dalam meningkatkan hasil tanaman. Tujuan penelitian ini untuk mengetahui pengaruh tumpang sari Crotalaria juncea dengan kedelai terhadap keanekaragaman serangga pengunjung bunga dan polinator alami terhadap hasil kedelai. Penelitian dirancang pada petak tunggal, dengan perlakuan: tanpa C. juncea (kontrol), penanaman C. juncea mengelilingi lahan kedelai, penanaman C. juncea setiap 5 baris kedelai, dan penanaman C. juncea setiap 10 baris kedelai. Pengaruh polinator alami terhadap hasil kedelai diamati melalui penyungkupan tanaman dengan jaring serangga. Hasil penelitian menunjukan, bahwa penanaman C. juncea dapat meningkatkan keanekaragaman serangga pengunjung bunga. Indeks keanekaragaman tertinggi 2,37 tercatat pada petak penanaman C. juncea setiap 10 baris kedelai. Keanekaragaman serangga pengunjung bunga terbanyak, yaitu 18 spesies ditemukan pada perlakuan penanaman C. juncea setiap 5 baris kedelai. Serangga pengunjung bunga yang dominan adalah Coccinella transversalis, Apis mellifera, Xylocopa virginica, Megachile parientina, Megachile relativa, Ropalidia fasciata, dan Vespa sp. Polinator alami (tanpa sungkup) dapat meningkatkan jumlah polong 30,11%, jumlah biji 44,63%, dan berat biji per tanaman 15,44% sehingga berperanan penting pada hasil kedelai.

Pollinator gardens more than triple in visitation rate and diversity of flower-visiting insects than other ornamental plantings in Kingston, Ontario

In this study I determined the effectiveness of pollinator gardens by testing if visitation rate and diversity of flower-visiting insects is higher in pollinator gardens compared to other ornamental plantings. I observed pollinator visitation for individual plant taxa, per unit area, in three different pollinator gardens, eight ornamental gardens and eight ornamental planters on the Queen’s University campus in Kingston, Ontario, Canada. Visitation was about 4- times higher in pollinator gardens compared to the other two ornamental garden types and visitor richness (the number of types of pollinators) in pollinator gardens was about 6- times higher compared to ornamental gardens, and about 3- times higher compared toornamental planters. The results of this study conclude that the planting of pollinator gardens is an effective way of supporting pollinator populations in urban areas.

Does Landscape Complexity and Semi-Natural Habitat Structure Affect Diversity of Flower-Visiting Insects in Cucumber Fields?

Presence of insects in agricultural habitat is affected by the surrounding circumstances such as the complexity and structure of landscape. Landscape structure is often formed as a consequence of the fragmentation of semi-natural habitat, which can negatively affect species richness and abundance of insects. This study was aimed to study the effect of complexity and structure of landscape on the diversity, abundance and traits of flower-visiting insects in cucumber fields. This study was conducted in cucumber fields surrounded by other agricultural crops, shrubs, semi-natural habitat and housing area, in Bogor, Cianjur and Sukabumi regencies, West Java, Indonesia. In a total of 16 agricultural areas, complexity and parameter of landscape especially class area (CA), number of patches (NumP), mean patch size (MPS), total edge (TE), and mean shape index (MSI) of seminatural habitats were measured. Sampling of flower-visiting insects was conducted using scan sampling methods. The result showed that landscape complexity affected species richness (but not abundance and trait) of flower-visiting insects both for mobile and less-mobile insects. Flower-visiting insects also responded differently to landscape structure. Species richness, abundance and variation of body size of mobile insects were affected by structure of semi-natural habitat.

Alpha and Beta Diversity of Flower-visiting Insects in Different Land Use Types

Alpha and Beta Diversity of Flower-visiting Insects in Different Land Use Types

Potensi serangga pengunjung bunga sebagai vektor penyakit darah bakteri (Ralstonia solanacearum Phylotipe IV) pada pisang di Sumatera Barat

Blood diseases caused by Ralstonia solancearum Phylotype IV is a major cause of production loss of banana in Indonesia, particularly for areas in West Sumatera. Currently there is a lack of information on blood diseases. The objective of this study was to obtain data of insect diversity and its potential as a dissemination agent of R. solanacearum Phylotype IV in West Sumatera. This research was conducted with a purposive sampling method in the Tabek Panjang highlands, District of Baso, Agam Regency and Pasar Usang lowland, district of Batang Anai, Pariaman Regency, West Sumatera. The results showed that banana plants infected by R. solanacearum Phylotype IV have a high diversity of flower-visiting insects. The diversity of insects in the lowlands is higher than that in highland and mainly are dominated by Trigona spp. (Hymenoptera: Apidae), Drosophila sp. (Diptera: Drosophilidae). To test the potential of both insect as vector of the blood diseases, isolated and identification of the bacteria using triphenyl tetrazolium medium chlorid (TTC) was used. Result showed that bacteria isolated from both insect are R. solanacearum hence providing evidence of the insect as vector of the blood diseases. Both insects have the potential to be vector of R. solanacearum Phylotype IV in West Sumatera. The identification of the bacteria that causes the disease. The identification of bacteria that is spread by flower visitors insects are R.solanacearum Phylotipe IV.

Is there a benefit of excluding sheep from pastures at flowering peak on flower-visiting insect diversity?

Permanent grasslands are an important habitat for insect communities, including pollinator populations which are in pan-European decline. Here, we investigated the benefits of temporarily excluding sheep from pastures on butterfly (Lepidoptera: Rhopalocera and Zygaenidae) and bumblebee (Hymenoptera: Bombidae) communities in two semi-natural grasslands differing in soil fertility and surrounding landscapes. We compared the impact of continuous grazing against rotational grazing (RG) at the same stocking rate but in which a subplot was excluded from the rotation during the main flowering period. We predicted that the diversity of flower-visiting insect community would be improved by RG due to the preservation of flower-rich patches and the maintenance of sward heterogeneity. Benefits of RG management were mainly evidenced on bumblebee density and species richness, with some additional effects on local density of butterflies during the subplot-exclusion period. Temporarily excluding sheep from pastures during peak flowering could thus offer an opportunity to preserve the diversity of flower-visiting insects, in spite of weaker benefits than could have been expected from previous surveys with cattle.

Diversity and abundance of flower-visiting insects in Bt and non-Bt cotton fields of Maputaland (KwaZulu Natal Province, South Africa)

We studied the abundance and diversity of flower-visiting insects on Bt and non-Bt cotton plants in the Makhathini Flats region of South Africa during the 2003/2004 and 2004/2005 crop seasons to detect any impact of the Bt toxin (Cry1Ac). Bt cotton cultivars produced more flowers than non-Bt cultivars regardless of the cropping conditions (farmers’ fields or research station), probably due to the fact that Bt cotton is not susceptible to flower bud pests. The results obtained in both crop seasons highlighted the prevalence of honeybees (Apis mellifera L.), various Nitidulidae and a unique Meloidae species (Mylabris oculata Thunberg) as flower visiting insects in this area. No impact of the Bt phenotype on insect abundance and diversity could be drawn on the basis of our comparative results on Bt and non-Bt cotton plants, and no direct effect of these transgenic plants was actually noted. The potential role of some of the inventoried insects, especially M. oculata, in the dispersal of transgenic pollen is discussed.

Food for insect pollinators on farmland: insect visits to flowers of annual seed mixtures

Intensification of agriculture in recent decades has impoverished farmland for insect pollinators by removing their food plants. Arable farmland can be enhanced as a habitat for these insects by growing annual nectar- and pollen-producing herbaceous plants for them in non-cropped areas such as set-aside and field margins. In 1996 and 1997, observations were made in Hertfordshire, UK, on the flowering phenology and flower-attractiveness to visiting Hymenoptera, Diptera and Lepidoptera of plots sown to mixtures of six annual flowering plant species: borage (Borago officinalis), buckwheat (Fagopyrum esculentum), cornflower (Centaurea cyanus), mallow (Malva sylvestris), marigold (Calendula officinalis) and phacelia (Phacelia tanacetifolia) in different proportions. The mixtures had good agronomic and biological properties. They established and flowered well from a range of seed rates and sowing-dates. They attracted a diversity of flower-visiting insects, including the honey bee and eightspecies of bumble bee amongst 16 species of aculeate Hymenoptera, 17 species of Diptera, mostly syrphids, and six species of Lepidoptera. Sequential sowings provided nectar and pollen from early summer to late autumn during the period after arable crops had finished flowering and food for pollinators was scarce. Different insect species were favoured by different sowing-dates and plant species