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Fire is a major ecological and evolutionary factor promoting biodiversity and maintaining functioning of naturally fire-prone ecosystems. In tropical savannas, plant communities show a set of fire-adapted traits and both flowering and pollination services have the potential to rapidly regenerate after fire, but fire-suppression policies may disrupt this adaptability following potential woody encroachment. Understanding the effects of fire on plant–pollinator interactions are required to advance conservation of biodiversity and ecosystem functioning. We evaluated the dynamics of plant community assemblage, flower availability, composition of flower functional traits associated with attractiveness to pollinators, and activity and diversity of insect pollinator guilds over ten post-fire stand ages along a 14-year chronosequence in a naturally burned region in the Cerrado, a megadiverse savanna in Brazil. We expect to find a high resilience of plant-pollinator communities and a steady decline in the successional recovery as time-since-fire proceeds. Along the post-fire chronosequence, vegetation was dominated by subshrubs with tubular, white, and nectar flowers arranged in inflorescences, while bees were the predominant pollinators. Plant assemblage and flower number showed an initial significant increase but monotonically declined after 7–9 years after fire. Accordingly, pollinator richness and abundance significantly reached highest peaks in interim periods and a steady decline over time. In contrast, the frequency of community-wide plant-life form, flower functional traits, and pollinator diversity remained unaltered over the post-fire chronosequence. We added compelling evidence of a high post-fire resilience of plant-pollinator communities and further understanding of how fire-suppression policies may affect pollination in the Cerrado. [ABSTRACT FROM AUTHOR]

Globally, insect pollinators that are linked to increased yields in many crops have experienced severe population declines. Crop diversification is often proposed as an effective conservation measure to boost pollinator populations. Here, we investigate the potential benefits of mixed oilseed rape/milk vetch cultivation for wild pollinator communities by comparing it with oilseed rape monocultures. Studying 8 mixed and 10 monocropping fields positioned along a gradient of increasing semi‐natural habitat coverage in mountainous agricultural landscapes, we found that agricultural landscapes with mixed cultivation harboured higher wild pollinator diversity than oilseed rape monocropping landscapes. This positive effect was observed irrespective of the proportion of semi‐natural habitat. Meanwhile, the pollinator community composition in mixed cultivation landscapes was similar to that of oilseed rape monoculture landscapes, and, contrary to expectations, mixed cultivation did not benefit specific pollinator trait groups like cavity‐nesting bees. Overall, we believe the higher pollinator diversity linked to mixed cultivation can increase insect‐pollinated crop yields, and mixed oilseed rape‐milk vetch cultivation might represent a potential mitigation measure for the negative impacts agricultural intensification has on wild pollinator communities. [ABSTRACT FROM AUTHOR]

Purpose: Insects constitute an important pollinator resource, and they are a key driver for both the fruit yield and the quality. It contributes in ensuring complete pollination and reproductive success of strawberries. However, the comprehensive benefits of insect pollinators in strawberry yield and fruit qualities through pollination are not quantified through empirical evidences. Therefore, this study quantifies the influence of pollinators on strawberry production. Research Method: The experiment was set up with two treatments (i.e., T1 - Open plots of strawberry, T2 - Mesh screen caged plot) arranged in a randomized complete block design with four replications per treatment. Opportunistic visual encounter and observational plot methods were followed to collect the insect pollinators sample. Further, the complete enumeration sampling was applied to collect strawberry plants sample. Findings: The results showed that during strawberry blossom, Tetramorium sp. was the prominent visitor (n = 506) followed by Apis cerana (n = 322). Based on the insects' foraging behavior, insect abundance and visit frequency, Apis cerana, Apis laboriosa, Xylocopa acutipennis, Bombus sp. and Junonia almana were recorded to be an effective Camarosa pollinator. The exclusion of pollinators in Camarosa resulted in smaller-sized and deformed fruits with inferior fruit quality attributes (color, shape and total soluble solids) compared to open plot fruits. The fruit quality attributes were significantly affected by pollination. Originality/Value: This study is the first of its kind to record the insect pollinators visiting Camarosa cultivar and study reported Tetramorium sp. as a successful pollinator in strawberries for the first time. [ABSTRACT FROM AUTHOR]

Onion (Allium cepa L.) is a highly cross pollinated crop that needs insect pollination (entomophily) for optimum seed set. In the present study, more than 120 insect species were noted to visit onion flowers, out of which fifty-nine species were collected through in-situ sampling technique and identified up to species level. The Indian bee (Apis cerana indica) was the most abundant insect pollinator visiting onion flowers in the study location. The pollination behaviour and foraging activity of A. c. indica were assessed, and the pollen foragers were observed to be swift flyers visiting a significantly higher number of flowers per minute during the peak flowering period and spending less time per flower (3 seconds) to collect nectar from deep seated nectaries of the flowers. The seed yield enhancement assessed through entomophily and artificial pollination methods showed that the open pollinated flowers recorded the highest yield statistically, followed by A. c. indica and A. mellifera pollinated flowers. However in artificial pollination treatments, sponge puff pollinated flowers recorded significantly high seed yield per hectare and percentage seed set per umbel, followed by camel brush, hand gloves (cloth) and hand gloves (rubber). In conclusion, all the cross pollination treatments were statistically significant on the closed pollination treatment concerning to the entire yield parameters calculated. [ABSTRACT FROM AUTHOR]

This study on pollinator diversity and abundance of frequent floral visitors was conducted during on coriander during rabi 2019-20 in Lalapuram village of Kallikudi block, Madurai district. Coriander flowers were observed to be visited by 25 pollinators. Among the visitors, four species were hymenopterans belonging to Apis (16%) and six from Non- Apis spp. (24%) Four belonged to Lepidoptera and Diptera (16%), three from Hemiptera and Coleoptera (12%) and one from Araneae (4%). Among all these, Apis florea was the most dominant one among Apis spp. followed by Apis cerana indica and Tetragonula iridipennis. The foraging activity and Shannon- Weiner's diversity index (2.78) was observed to be maximum during 1000- 1200 hrs. [ABSTRACT FROM AUTHOR]

Pollinating insects provide pollination services to many crop species, including sweet cherry (Prunus avium L.), and this can be delivered by both managed and wild pollinators. Managed pollinators are often used to pollinate a range of fruit crops, but increasingly the role of wild insects is being studied. However, the importance of pollinator species depends on their relative abundance and pollination effectiveness, which depends on their foraging activity and their variability throughout the day. In this study, insect visitors of blossoms were observed in commercial sweet cherry orchards to explore abundance, diversity and pollination foraging behaviour of different insect pollinator groups throughout the day. A total of 1,174 pollinators from 31 different species were recorded visiting cherry blossoms over 2 years, of which 71.0% of total visits were by managed pollinators (western honeybee, Apis mellifera L. and buff‐tailed bumblebee, Bombus terrestris L.) compared to 29.0% by wild pollinators. On average, solitary bees visited a sweet cherry blossom for the longest duration (20.7 (±2.0 SE) seconds), whereas wild queen bumblebees visited the greatest number of flowers per minute (mean of 19.0 (±1.3 SE)). As both these pollinator groups contacted cherry stigmas more often and moved more frequently between tree rows than managed bees and hoverflies, they are more likely to facilitate cross‐pollination. The different pollinator groups also showed variation in behavioural parameters throughout the day, but less variation was recorded when all pollinator groups were considered altogether. This suggests diverse pollinator communities might be expected to provide a more stable pollination service to sweet cherry. This study demonstrates that whilst cherry blossoms were more frequently visited by managed pollinators, wild solitary bee and bumblebee behaviours are likely to be more effective at enhancing pollination in sweet cherry orchards, which, in turn, might lead to increased yields. [ABSTRACT FROM AUTHOR]

Studying pollinator diversity and their abundance is essential to analyze the health of the agroecosystem. This study undertook observations on the number of pollinators visiting the flowers/m2 for 5 min at randomly selected ten spots in the agroecosystems in West Bengal. The diversity index was measured by Simpson's Index of Diversity. A total number of 55 individuals of insect pollinators belonging to 19 families and four orders were observed of which Hymenoptera were maximum (47.25%) followed by: Coleoptera (24.68%), Lepidoptera (11.26%) and Diptera (8.29%). Simpson's index ranged from 0 to 1. and maximum species richness was found in Lower Bongbasti, Kalimpong (0.995) and the least at ABBlock farm BCKV Kalyani (0.751). Among the surveyed areas, species evenness was found maximum in Khelia North 24 Parganas (1.34) and the least in Jhanti Pahari Bankura (0.14). So far as pollinator species richness is concerned, it was maximum in hilly terrains of Kalimpong followed by North 24 Parganas, Bankura and Nadia. [ABSTRACT FROM AUTHOR]

To increase the resilience of our food system, we must better understand how ecosystem services such as pest control and pollination provided by a diverse insect community contribute to crop yield. We examined how landscape heterogeneity relates to insect and pollinator diversity, and how insect and pollinator diversity relates to yield of Brassica carinata, a new biofuel crop within common farming practices. Over two years, we planted 35 × 1 acre sites in a roughly 1000‐km2 area near Brookings, South Dakota, in the Prairie Coteau. We randomly assigned each site to a combination of three common farming practices: tilling (yes/no), added honey bee hives (yes/no), and treatment with systemic neonicotinoids (yes/no). Insect and pollinator diversity and the heterogeneity of the surrounding landscape at multiple spatial scales were calculated. We observed a significant positive relationship between insect (and pollinator) diversity and yield when fields were untreated, without hives, nor seed treatments. All farming practices within this study increase yield. However, farming practices alter the relationship between yield and insect (and pollinator) diversity. The addition of seed treatment or tillage negates the relationship between insect (and pollinator) diversity with yield. There was no relationship between seed treatment, diversity, and yield for all insects, and the application of seed treatment resulted in lower pollinator diversity. Increased landscape heterogeneity was correlated with more insect diversity at the 1000‐m scale and pollinator diversity at the 3000‐m scale. Our results show that increasing large‐scale landscape heterogeneity increases insect diversity, which serves as a substitute for common farming practices such as application of pesticides, tilling, or bee hives. Increased landscape heterogeneity could increase farmers' net profitability by replacing input costs associated with tillage and seed treatments. [ABSTRACT FROM AUTHOR]

Pollinators are rewarding for many wild and agricultural crop plants. The experiments were conducted in the agricultural field of Karad tehsil, Maharashtra, India. The present study concentrated on the diversity and species richness of nocturnal insect pollinators on Ridge gourd Luffa acutangula belonging to the family Cucurbitaceae. The Ridge gourd plant is monoecious with a bunch of male flowers and solitary female flower. Anthesis happened in late evening hours (17.00-19.00) and flowers remained for 13 to 14 hours. A total of 830 insect pollinators were sampled from June 2020 to November 2020. Altogether 17 species of insect pollinators belonging to 7 families under 6 orders were recorded. Among the total number of species, the Lepidoptera was the dominant order comprising 11 species belonging to the single family Crambidae followed by Blattodea comprising 2 species belonging to 2 families Ectobiidae and Blattidae. Hymenoptera comprised 1 species belonging to family Formicidae, followed by order Orthoptera comprising 1 species belonging to family Gryllidae, order Diptera comprising 1 species belonging to the family Culicidae, followed by the order Coleoptera comprising 1 species belonging to the family Chrysomelidae. The Diaphnia hyalinata belonging to family Crambidae of the order Lepidoptera was the most dominant species and was followed by Chabula acamasalis. The nocturnal species imparted pollination services to agricultural crops. The study also observed fundamental mechanisms of plant and nocturnal insect pollinator interaction as well as floral scent and visual signals. The study can be baseline data for conserving and managing the best pollinators for increasing the yield of Ridge gourd. [ABSTRACT FROM AUTHOR]

Declines in pollinating invertebrates across intensively cultivated landscapes linked to reductions in flower‐rich habitats constitute a key threat to biodiversity conservation and the provision of ecosystem services. Over recent decades, many ponds in agricultural landscapes have become overgrown with woody vegetation, resulting in heavily shaded, flower‐poor pond basins and margins. Restoration of farmland ponds through removal of sediment and encroaching woody vegetation (canopy management) from pond margins greatly enhances freshwater biodiversity. Nevertheless, the consequences of pond management for pond‐margin plants and pollinating insects remain poorly understood. Here, we studied these effects for ponds in Norfolk, eastern England.We compared richness, abundance and composition of pollinating insects (hymenopterans and syrphids) and insect‐pollinated plant communities between open‐canopy pond systems subjected to either (i) long‐term regular management of woody vegetation or (ii) recent restoration by woody vegetation and sediment removal with those communities at (iii) ponds dominated by woody vegetation.Canopy management increased the richness and abundance of pollinators and insect‐pollinated plants. Pollinator richness and abundance was best explained by improvements in flower resources at open‐canopy ponds. Management most strongly influenced hymenopteran communities.Ponds represent important semi‐natural habitats for insect‐pollinated plant and pollinator communities in farmland. To enhance food resources, diversity and abundance of diurnal pollinators, conservation management at ponds should aim for mosaics of ponds at different successional stages with a high proportion of early successional open‐canopy ponds. Agricultural ponds are emerging as important habitats not only for aquatic biodiversity, but also for terrestrial species, thus warranting their prioritisation in future agri‐environment schemes. [ABSTRACT FROM AUTHOR]

White clover (Trifolium repens L.) seed crops require insects for pollination. Apis mellifera Linnaeus, 1758 are normally placed within fields but other insects might also be contributing additional pollination. To understand their potential contribution, we evaluated abundances across fields during peak flower; measured loose body pollen on four bee and two fly species and compared the rate of movement between inflorescences and florets for A. mellifera and B. terrestris (Linnaeus, 1758). A. mellifera were the most abundant verified flower visitor, although B. terrestris and long-tongued Bombus species also visited fields. Other insects recorded included Lasioglossum bees and two hover fly species, but these were considered ineffective pollinators (either low abundances or carried few pollen grains). B. terrestris were considered a more efficient pollinator than A. mellifera moving faster between florets but were less effective due to low abundances. Many Bombus spp. will forage under weather conditions unfavourable to A. mellifera, therefore, providing complimentary pollination. [ABSTRACT FROM AUTHOR]

A wide variety of insect species provide pollination services in natural and agricultural ecosystems, but in order to quantify their contribution it is necessary to evaluate their effectiveness. An important component of this is to determine their ability to transfer pollen to stigmas which typically requires observers to wait for insects to visit focal flowers (static approach); a time-consuming process not amenable to obtaining measures for pollinating species of low local abundance. An alternative method (active approach) is to detach test flowers and present them to the targeted flower visitor. This offers a number of advantages ( e.g. increased speed and flexibility), but may alter insect behaviour. We compared pollen deposition within flowering onion crops using three bee (Apoidea) and three fly (Diptera) species. The two approaches resulted in similar numbers of pollen grains being deposited onto stigmas for each insect species, thereby supporting the validity of the active as an alternative to the static approach in our test crop. The ability to rapidly assess stigmatic pollen deposition of a broad range of insects using the active approach can greatly assist assessments of pollinator contribution within plant pollinator assemblages. [ABSTRACT FROM AUTHOR]

Different pollinators may vary in their temporal flower-visitation patterns within crops, potentially extending the period pollination may occur. To assess whether this could be the case in kiwifruit, we conducted standardised observational surveys of insects visiting kiwifruit flowers within 31 orchards at three times: 10:00-11:00, 12:00-13:00 and 14:00-15:00 hr. Honey bees (Apis mellifera) represented 92% of visitations (n=5474), but temporal abundances were uneven (predicted abundances were lower at 14:00-15:00 hr). Predatory hover flies (Melangyna, Melonostoma, Allograpta spp.) also showed an uneven temporal pattern. There were no significant differences in the temporal abundances for buff-tailed bumble bees (Bombus terrestris), rattailed hover flies (Eristalis, Helophilus spp.), March flies (Dilophis nigrostigma), flower longhorn beetles (Zorion guttigerum) or the native bees (Leioproctus and Lasioglossum spp.) although, in some cases, low numbers may have masked potential unevenness trends. Variation in diurnal flower-visitation patterns among insects suggests the potential for complementarity between different pollinators. [ABSTRACT FROM AUTHOR]

Insect pollination is key to ensuring adequate fruit yields within avocado orchards. Various bee and non-bee insect species have been considered as potential pollinators of avocado worldwide, but in New Zealand there has been little research into which insect species visit avocado flowers. In the Bay of Plenty, an important avocado production area, flower visitor abundance and diversity data were obtained by conducting observational surveys in four orchards in November 2015. Honey bees were the dominant flower visitors in all orchards surveyed, representing 92.9% of all insects recorded, but there was high variation in numbers among sites. Other common insects observed included the beetle, Zorion guttigerum (3.4%), and bumblebees Bombus spp. (1.6%). A better understanding of the interaction between honey bee stocking rates and flower visitor abundances within orchards could assist in improving pollination recommendations. [ABSTRACT FROM AUTHOR]

Present study was carried out to determine pollinators' diversity and their efficiency with modular approach; foraging behaviour, number of loose pollen adhered on their body and number of pollen deposited on the stigma. The observations explicitly indicate that Megachile spp., Xylocopa tenuiscopa, Amegilla zonata and Nomia sp. were true pollinators and out of these, Megachile spp. were key pollinators of pigeonpea. Among megachilids, Megachile lanata was the most efficient pollinator. Sufficient pollination meticulously accomplished in pigeonpea by true pollinators under this agro-ecological region. [ABSTRACT FROM AUTHOR]