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NUGROHO, ARI, TRI ATMOWIDI e SIH KAHONO. "Diversitas Serangga Penyerbuk dan Pembentukkan Buah Tanaman Kakao (Theobroma cacao L.)". Jurnal Sumberdaya Hayati 5, n. 1 (24 giugno 2019): 11–17. http://dx.doi.org/10.29244/jsdh.5.1.11-17.
Testo completoAbstract (sommario):
Cocoa (Theobroma cacao L.) is an entomophilous plant which is need insects for pollination. Pollinator insects increase cocoa’s fruit set. The aim of this research were to study diversity of pollinator insects, visiting activity of fly, Forcipomyia (Diptera), and fruit set of cocoa. Observation of pollinator insects was conducted by scan sampling method. Visiting activity of Forcipomyia were observed based on duration visit per flower, number of flowers visited per minute, and duration of activity on flowers. Pollen load on body of Forcipomyia were measured. Pollination effectiveness of insect were measured from the number and size of the cocoa fruit. Result showed that 19 species of insects visitors on cocoa flowers were observed. Nine species are pollinator of cocoa’s plants i.e. Forcipomyia, Cecidomyia, Stilobezzia, Drosophila, Orimarga, Dolichoderus, Pheidole, Megachile, and Nomia. Cocoa pollination by insects produced 3% fruit higher than flowers without insect pollination. Pollination by insects produced size and weight of fruit, and number of seed per fruit were higher than pollination without insects.
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Kusuma, Ramadhani Mahendra, e Wiwin Windriyanti. "Effective Behavior of Insects Pollinators of Flowers in Gadung Mango Clone 21 Variety". Jurnal Ilmu Pertanian Indonesia 27, n. 4 (25 ottobre 2022): 596–605. http://dx.doi.org/10.18343/jipi.27.4.596.
Testo completoAbstract (sommario):
Pollinating insects are referred as support services, namely services by the processes in the ecosystems that support human well-being by maintaining or enhancing ecosystem services. The availability of flowers, diversity, and behavior of visiting pollinator insects affect the effectiveness of pollination to increase the formation of fruit sets of mango plants. The purpose of this study is to observe the behavior of pollinator insects visiting the mango gadung clone 21 varieties and their effectiveness in increasing the formation of fruit sets. Research has been carried out on two flower seasons: March-May (Off season) and July-September (On season) 2020. Visiting behaviors observed were the number of visits per minute (foraging rate) and the length of visit per flower (flower handling time). Pollination effectiveness was measured from the number of fruit sets formed from the open flower panicles and confined with a tangerine gauze. The results of the study obtained seven species including Apis sp., Trigona sp., Xylocopa sp., Polistes sp. 1, Polistes sp. 2, Chrysomya sp., and Eristalis sp. Visits of pollinating insects on the highest number of mango panicle flowers were (31.69 ± 7.69) flowers / 60 seconds by Trigona sp insects, and the lowest numbers were (2.70 ± 0.67) flowers / 60 seconds by Eristalis sp. insects. The longest visits of pollinator insects on mango flowers were obtained by Eristalis sp for (25.3 ± 8.50) sec/individual/flower and the shortest visits were by Trigona sp for (1.8 ± 0.63) seconds/individual/flower. Insect pollination increases fruit formation by 267.5%.
Keywords: insect visits, pollinating insects, fruit formation, gadung 21 varieties mango
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Alfawwaz, Muhammad Dzaky, Agus Dana Permana e Ramadhani Eka Putra. "Diversity and Abundance of Insects Pollinator of Chayote (Sechium edule (Jacq.) Swartz". Jurnal Biodjati 7, n. 1 (30 maggio 2022): 36–44. http://dx.doi.org/10.15575/biodjati.v7i1.13881.
Testo completoAbstract (sommario):
Chayote plants (Sechium edule) with monoecious characters require a pollination process. The pollination process requires pollinating agents to increase its productivity, one of which is insects. This research aimed to determine the diversity and abundance of insects pollinator on chayote plants. Observation of diversity and abundance used a scan sampling method. Pollinator insects observations were carried out in 3 time periods, morning, afternoon, and evening on male and female flowers. We measured environmental parameters such as temperature, humidity, wind speed, and light intensity. Eight species of wild insects pollinated chayote flowers, Apis cerana, Apis dorsata, Lasioglossum leucozonium, Polistes sagittarius, Phimenes flavopictus, Campsomeriella annulata, Lucilia sericata, and Musca domestica. The insect pollinators community had moderate diversity (1.23), a relatively dynamic community (0.59), and moderate dominance (0.62), with A. cerana, which had been the dominant insect pollinator with a relative abundance of 61.63%. Musca domestica and L. sericata were (0,58%) the least dominant insect pollinator with a relative abundance of 0.58%. This research concludes that the insects pollinator of chayote has a moderate level of diversity, relatively dynamic community, and average dominance.
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Wayo, Kanuengnit, Chama Phankaew, Alyssa B. Stewart e Sara Bumrungsri. "Bees are supplementary pollinators of self-compatible chiropterophilous durian". Journal of Tropical Ecology 34, n. 1 (gennaio 2018): 41–52. http://dx.doi.org/10.1017/s0266467418000019.
Testo completoAbstract (sommario):
Abstract:Nocturnally foraging insects may be supplementary pollinators to chiropterophilous plant species when bats are scarce. Given that insects are much smaller than bats, they may be more effective at transferring pollen for plant species with similar stamen and pistil lengths, such as the ‘Monthong’ durian cultivar. The present study clarifies the role of insects in pollinating the ‘Monthong’ cultivar by examining the floral biology, conducting pollination treatments on 19 trees and observing floral visitors in southern Thailand. Stigmas were receptive by 17h00, and over 50% of ‘Monthong’ anthers had dehisced by 17h30. Several bee species began foraging on flowers during the late afternoon, and the giant honey bee (Apis dorsata) continued to visit throughout the night. Our results show that at 4 wk after pollination, the highest fruit set occurred from hand-crossed pollination (13.5%), followed by open pollination (5.5%), insect pollination (3.3%) and automatic autogamy (2.0%), indicating that this cultivar is highly self-incompatible. Moreover, insects appear to be important pollinators of ‘Monthong’ durian in areas where nectar bats visit infrequently. One bee species in particular,Apis dorsata, commonly foraged on flowers at dusk and appears to be the most effective insect pollinator of durian. Our findings highlight that nocturnally foraging bees are capable of securing pollination for night-blooming plant taxa, even those typically considered to be bat-pollinated.
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Allifah AF, Asyik Nur, Farida Bahalwan e Nur Alim Natsir. "Keanekaragaman Dan Kelimpahan Serangga Polinator Pada Perkebunan Mentimun (Cucumis sativus L) Desa Waiheru Ambon". Biosel: Biology Science and Education 9, n. 1 (31 maggio 2020): 26. http://dx.doi.org/10.33477/bs.v9i1.1314.
Testo completoAbstract (sommario):
Pollinator insects are insects that play a role in pollination, namely intermediaries pollinating plants. The purpose of this study was to determine the abundance and diversity of insects pollinators in the Cucumber (Cucumis sativus L) Plantation of Waiheru Village, Baguala District, Ambon City. Sampling was done by purposive sampling using a yellow glue trap (Yellow sticky trap). The customer observations are made in visual control. Observation starts at 07.00 WIT until 18.00 WIT which is divided into 3 time periods, namely: 07.00-10.00 WIT, 11.00-14.00 WIT and 15.00-18.00 WIT. The data obtained were analyzed using the diversity index (H ') according to Shannon and Wiener. The results showed that the total abundance of pollinator insects in vegetable plantations was 1220 individuals, consisting of 3 orders and 5 families. Insect families that play a role in the process of pollination are Family Apidae, Formicidae, Syrpidae, Muscidae and Papilionidae. The highest abundance of insects is dominated by the Formicidae Family while the lowest abundance is the Papilionidae Family. Value insect pollinator diversity found among the sites that H '= 1.21 which indicates that the level of diversity of insect pollinators on plantations Cucumber (Cucumis sativus L) in the Waiheru Village, Baguala District, Ambon City in the medium category.
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Vaz, Carlos G., Domingos de Oliveira e Orlando S. Ohashi. "Pollinator Contribution to the Production of Cowpea in the Amazon". HortScience 33, n. 7 (dicembre 1998): 1157–59. http://dx.doi.org/10.21273/hortsci.33.7.1157.
Testo completoAbstract (sommario):
Cowpea, Vigna unguiculata (L.) Walp., is a very important legume in the diet of the population of the Amazon. Although it is autogamous, this species has a cross-pollination rate of ≈10%. Over several years, the mean productivity of cowpea has declined. We suggest that this is linked to a decrease in or an absence of pollinating insects in the fields. The objective of this study is to ascertain the pollinator contribution to cowpea production, as well as to determine the pollination type of the `BR3-Tracuateua' cultivar. In an experimental design, four treatments were compared: no pollination, with flowers in cages to prevent insect visits; open-pollination, with flowers exposed to all visiting insects; self-pollination, with flowers pollinated with their own pollen; and cross-pollination, with emasculated flowers being pollinated manually with pollen from another plant. We observed higher fruit set in the presence of pollinators (83%) than in their absence (77%, caged flowers). However, cross-pollination reduced both the number of seeds per pod and fruit set relative to self-pollination. This result suggests that pollinators have a complementary role in the yield of cowpea, by creating a mixed pollination system where self-pollination dominates.
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SITOMPUL, AIDA FITRIANI, ELIDA HAFNI SIREGAR, DEWI IMELDA ROESMA, DAHELMI DAHELMI e EKO PRASETYA. "Molecular identification of coffee (Coffea arabica) pollinator insects in North Sumatra, Indonesia based on designed COI primers". Biodiversitas Journal of Biological Diversity 19, n. 5 (21 settembre 2018): 1876–83. http://dx.doi.org/10.13057/biodiv/d190540.
Testo completoAbstract (sommario):
Sitompul F, Siregar EH, Roesma DI, Dahelmi, Prasetya E. 2018. Molecular identification of coffee (Coffea arabica) pollinator insects in North Sumatra, Indonesia based on designed COI primers. Biodiversitas 19: 1877-1883. Coffee (Coffea arabica L.) is one of the most important economic commodities in the province of North Sumatra, Indonesia. Insects associated with pollination of C. arabica are one of the key factors for successful cultivation of C. arabica, but, the research regarding of these was still limited. The population of coffee plant is scattered across the highlands of Indonesia and the pollination of C. arabica is strongly believed linked to a diverse group of pollinating insects. However, lack of taxonomic identification of insects pollinating these plants has become one of constraints to succeed the cultivation of C. Arabica. This study aimed to analyze types and variations of pollinating insects of C. arabica in the province of North Sumatra, Indonesia, using DNA barcoding. DNA barcoding is now considered an alternative method of molecular identification. Sixteen of C. arabica flower visitors were captured in different planting location in North Sumatra province. Using mtDNA markers, the cytochrome oxidase subunit sequence I (COI), about 12 pollinator insect species were identified based on the COI sequence i.e Amegilla cingulata, Apis dorsata, Apis cerana, Trigona chanchamayoensis, Idiella divisa, Dolichopodidae sp., Allactoneura sp., Stomorhina discolor, Phytomia erratica, Rhiniidae sp., Melipona bicolor, and Hymenoptera sp.
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Li, Nannan, Yizhao Huang, Wei Li e Shufa Xu. "Virome Analysis Reveals Diverse and Divergent RNA Viruses in Wild Insect Pollinators in Beijing, China". Viruses 14, n. 2 (24 gennaio 2022): 227. http://dx.doi.org/10.3390/v14020227.
Testo completoAbstract (sommario):
Insect pollinators provide major pollination services for wild plants and crops. Honeybee viruses can cause serious damage to honeybee colonies. However, viruses of other wild pollinating insects have yet to be fully explored. In the present study, we used RNA sequencing to investigate the viral diversity of 50 species of wild pollinating insects. A total of 3 pathogenic honeybee viruses, 8 previously reported viruses, and 26 novel viruses were identified in sequenced samples. Among these, 7 novel viruses were shown to be closely related to honeybee pathogenic viruses, and 4 were determined to have potential pathogenicity for their hosts. The viruses detected in wild insect pollinators were mainly from the order Picornavirales and the families Orthomyxoviridae, Sinhaliviridae, Rhabdoviridae, and Flaviviridae. Our study expanded the species range of known insect pollinator viruses, contributing to future efforts to protect economic honeybees and wild pollinating insects.
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Labandeira, Conrad C. "The Paleobiology of Pollination and its Precursors". Paleontological Society Papers 6 (novembre 2000): 233–70. http://dx.doi.org/10.1017/s1089332600000784.
Testo completoAbstract (sommario):
Perhaps the most conspicuous of associations between insects and plants is pollination. Pollinating insects are typically the first and most obvious of interactions between insects and plants when one encounters a montane meadow or a tropical woodland. The complex ecological structure of insect pollinators and their host plants is a central focus within the ever-expanding discipline of plant-insect interactions. The relationships between plants and insects have provided the empirical documentation of many case-studies that have resulted in the formulation of biological principles and construction of theoretical models, such as the role of foraging strategy on optimal plant-resource use, the advantages of specialized versus generalized host preferences as viable feeding strategies, and whether “pollination syndromes” are meaningful descriptions that relate flower type to insect mouthpart structure and behavior (Roubik, 1989; Ollerton, 1996; Waser et al., 1996; Johnson and Steiner, 2000). Much of the recent extensive discussion of plant-insect associations has centered on understanding the origin, maintenance, and evolutionary change in plant/pollinator associations at ecological time scales and increasingly at longer-term macroevolutionary time intervals (Armbruster, 1992; Pellmyr and Leebens-Mack, 1999). Such classical plant-insect association studies—cycads and cycad weevils, figs and fig wasps, and yuccas and yucca moths—were explored at modern time scales and currently are being examined through a long-term geologic component that involves colonization models based on cladogenetic events of plant and insect associates, buttressed by the fossil record (Farrell, 1998; Pellmyr and Leebens-Mack, 1999; A. Herre,pers. comm.). In addition to tracing modern pollination to the earlier Cenozoic and later Mesozoic, there is a resurgence in understanding the evolutionary history of earlier palynivore taxa (spore, prepollen and pollen consumers), which led toward pollination as a mutualism (Scott et al., 1992).
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Eeraerts, Maxime, Lieve Borremans, Guy Smagghe e Ivan Meeus. "A Growers’ Perspective on Crop Pollination and Measures to Manage the Pollination Service of Wild Pollinators in Sweet Cherry Cultivation". Insects 11, n. 6 (15 giugno 2020): 372. http://dx.doi.org/10.3390/insects11060372.
Testo completoAbstract (sommario):
Recent declines in insect pollinators and the increasing dependence on insect pollination in agriculture present major challenges to ensuring future food production. As part of the effort to deal with this challenge, there is a pressing need to understand growers’ perceptions with regard to pollinator diversity and crop pollination management. At present, many growers are dependent on domesticated honey bees (Apis mellifera), however, targeted management strategies involving naturally occurring pollinator species might be necessary to ensure future crop pollination. In this study we used semi-structured interviews to explore growers’ knowledge about crop pollination and current practices to manage insect pollination in sweet cherry cultivation. Our findings suggest that growers have a clear understanding of the importance of pollination and its determining factors. However, with respect to their current pollination management, growers depend mainly on honey bees and only apply measures to enhance wild pollinator communities to a limited extent. Our study highlights the gap between the growers’ perception of the contribution of wild pollinators to crop pollination, and their efforts to manage these species. We conclude that this is due to a lack of communication of recent scientific findings on the contribution of pollinating insects to crop pollination through the information channels that are being used by growers today. It is therefore crucial that scientists, government and other stakeholders work together with growers and communicate scientific evidence as well as practical guidelines to growers.
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Mangla, Yash, e Rajesh Tandon. "Insects facilitate wind pollination in pollen-limited Crateva adansonii (Capparaceae)". Australian Journal of Botany 59, n. 1 (2011): 61. http://dx.doi.org/10.1071/bt10174.
Testo completoAbstract (sommario):
Low fruit-set in obligately outbreeding plant species is attributed to a variety of reasons that can be ascertained from reproductive studies. In the present work, the causes of poor natural fruit-set in Crateva adansonii DC. were investigated. Floral biology, the role of wind and insects in pollination and the breeding system of the species were studied in two natural populations for three consecutive seasons (2006–08). The flowers exhibited traits conducive to a mixture of wind and insect pollination (ambophily). Although a variety of insects visited the flowers, they were ineffective in pollinating. Nevertheless, active foraging by the honeybees (Apis dorsata, A. mellifera and A. cerana indica) facilitated enhanced pollen dispersal in the air and resulted in indirect pollination by wind. Airborne pollen grains pollinated the plants only up to 10 m. Fruit-set from open pollination was comparable to wind-pollinated flowers. Supplemental pollination treatments established the occurrence of strong self-incompatibility (SI) (index of SI = 0.14). Spontaneous autogamy was prevented by pronounced herkogamy. Low natural fecundity in C. adansonii is due to pollination failure, pollen limitation (pollen limitation index = 0.98) and the sparse distribution of the conspecifics; partial SI may partly ensure reproductive assurance through geitonogamy. In the absence of a pollinator wind appears to act as a secondary mode of pollination.
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Freitas, B. M., e R. J. Paxton. "The role of wind and insects in cashew (Anacardium occidentale) pollination in NE Brazil". Journal of Agricultural Science 126, n. 3 (maggio 1996): 319–26. http://dx.doi.org/10.1017/s0021859600074876.
Testo completoAbstract (sommario):
SUMMARYThe pollination requirements of cashew (Anacardium occidentale L.), an andromonoecious tree, were studied in NE Brazil, where cashew is indigenous. It was shown through the use of bagging and caging experiments, controlled hand-pollination and emasculation of flowers, that the wind plays little role in cashew pollination and that cashew is self-fertile, although only pollen from the large stamen, either male or hermaphrodite-derived, can effect pollination. Insects appear to be the major pollinators of cashew, in agreement with the pollination syndrome suggested by the morphology of its flowers. Direct observations of insects visiting flowers and counts of pollen grains adhering to such insects suggest that the honey bee (Apis mellifera L.), although a non-native insect, is the major pollinator of commercially grown cashew in NE Brazil.
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Hall, John A., e Gimme H. Walter. "Pollination of the Australian cycad Cycas ophiolitica (Cycadaceae): the limited role of wind pollination in a cycad with beetle pollinator mutualists, and its ecological significance". Journal of Tropical Ecology 34, n. 2 (marzo 2018): 121–34. http://dx.doi.org/10.1017/s0266467418000111.
Testo completoAbstract (sommario):
Abstract:Cycads in the Zamiaceae are well known for their host-specific insect pollination mutualisms. Pollination of Cycas in the sister family Cycadaceae is less well-documented, with beetle pollination possibly coexisting with a limited potential for wind pollination, a hypothesis we tested for C. ophiolitica in Central Queensland, Australia. Cones were associated with three species of beetle: an undescribed weevil (Curculionidae), Hapalips sp. (Erotylidae) and Ulomoides sp. (Tenebrionidae). Pollination-vector exclusion experiments compared the pollination success (quantified as % ovules pollinated per cone) of control cones against bagged or netted cones that excluded wind or insects respectively (n = 10 for all treatments). Insects do pollinate C. ophiolitica in the absence of wind, the median (first quartile-third quartile) pollination success of control plants being 83.7% (60.8–87.2%) while bagged cones, from which wind, but not insects, were excluded, pollinated at 52.9% (19.5–74.8%). For netted cones, (excluding insects but not wind), pollination fell to 12.6% (10.9–45.9%). Airborne pollen (as quantified by capture on a series of adhesive pollen traps) decreased rapidly with distance from male cones, potentially becoming ineffective for wind pollination at ~5 m. Airborne pollen load in the vicinity of female cones, and distance of females from neighbouring males, suggests wind pollination may occur sporadically, but only at high spatial densities. Although Cycas appears to be primarily insect pollinated, this limited potential for ambophily may be significant given the history of dispersal and pollinator host shifts among these cycads.
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Cunningham, Saul A., Frances FitzGibbon e Tim A. Heard. "The future of pollinators for Australian agriculture". Australian Journal of Agricultural Research 53, n. 8 (2002): 893. http://dx.doi.org/10.1071/ar01186.
Testo completoAbstract (sommario):
Agriculture in Australia is highly dependent on insect pollination, in particular from the introduced western honeybee, Apis mellifera. Most agricultural pollination is provided as an unpaid service by feral A. mellifera and native insects. A smaller proportion of agricultural pollination is provided as a paid service by beekeepers. Insect pollination is threatened by misuse of insecticides and the loss of remnant vegetation, but most potently by the likelihood that the honeybee mite, Varroa destructor, will enter the country. Now is the time to prepare for the effect of these changes, and international experience with pollinator decline should serve as a guide. We need to protect and manage our remnant vegetation to protect wild pollinators. Insurance against declining A. mellifera will come through the development of management practices for alternative pollinator species. By developing native insects as pollinators we can avoid the risks associated with the importation of additional introduced species.
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Kleiman, Blaire M., Suzanne Koptur e Krishnaswamy Jayachandran. "Weeds Enhance Pollinator Diversity and Fruit Yield in Mango". Insects 12, n. 12 (13 dicembre 2021): 1114. http://dx.doi.org/10.3390/insects12121114.
Testo completoAbstract (sommario):
Agriculture is dependent on insect pollination, yet in areas of intensive production agriculture, there is often a decline in plant and insect diversity. As native habitats and plants are replaced, often only the weeds or unwanted vegetation persist. This study compared insect diversity on mango, Mangifera indica, a tropical fruit tree dependent on insect pollination, when weeds were present in cultivation versus when they were removed mechanically. The pollinating insects on both weeds and mango trees were examined as well as fruit set and yield in both the weed-free and weedy treatment in South Florida. There were significantly more pollinators and key pollinator families on the weedy mango trees, as well as significantly greater fruit yield in the weedy treatment compared to the weed-free treatment. Utilizing weeds, especially native species, as insectary plants can help ensure sufficient pollination of mango and increase biodiversity across crop monocropping systems.
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Howard, Scarlett R., Malika Nisal Ratnayake, Adrian G. Dyer, Jair E. Garcia e Alan Dorin. "Towards precision apiculture: Traditional and technological insect monitoring methods in strawberry and raspberry crop polytunnels tell different pollination stories". PLOS ONE 16, n. 5 (14 maggio 2021): e0251572. http://dx.doi.org/10.1371/journal.pone.0251572.
Testo completoAbstract (sommario):
Over one third of crops are animal pollinated, with insects being the largest group. In some crops, including strawberries, fruit yield, weight, quality, aesthetics and shelf life increase with insect pollination. Many crops are protected from extreme weather in polytunnels, but the impacts of polytunnels on insects are poorly understood. Polytunnels could reduce pollination services, especially if insects have access issues. Here we examine the distribution and activity of honeybees and non-honeybee wild insects on a commercial fruit farm. We evaluated whether insect distributions are impacted by flower type (strawberry; raspberry; weed), or distance from polytunnel edges. We compared passive pan-trapping and active quadrat observations to establish their suitability for monitoring insect distribution and behaviour on a farm. To understand the relative value of honeybees compared to other insects for strawberry pollination, the primary crop at the site, we enhanced our observations with video data analysed using insect tracking software to document the time spent by insects on flowers. The results show honeybees strongly prefer raspberry and weed flowers over strawberry flowers and that location within the polytunnel impacts insect distributions. Consistent with recent studies, we also show that pan-traps are ineffective to sample honeybee numbers. While the pan-traps and quadrat observations tend to suggest that investment in managed honeybees for strawberry pollination might be ineffective due to consistent low numbers within the crop, the camera data provides contrary evidence. Although honeybees were relatively scarce among strawberry crops, camera data shows they spent more time visiting flowers than other insects. Our results demonstrate that a commercial fruit farm is a complex ecosystem influencing pollinator diversity and abundance through a range of factors. We show that monitoring methods may differ in their valuation of relative contributions of insects to crop pollination.
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Rosa, Annelise de Souza, Betina Blochtein e Diego Kweco Lima. "Honey bee contribution to canola pollination in Southern Brazil". Scientia Agricola 68, n. 2 (aprile 2011): 255–59. http://dx.doi.org/10.1590/s0103-90162011000200018.
Testo completoAbstract (sommario):
Although canola, (Brassica napus L.), is considered a self-pollinating crop, researchers have indicated that crop productivity increases as a result of honey bee Apis mellifera L. pollination. Given this crop's growing importance in Rio Grande do Sul State, Brazil, this work evaluated the increase in pod and seed productivity with respect to interactions with anthophilous insects and manual pollination tests. The visiting frequency of A. mellifera was correlated with the crop's blooming progression, and productivity comparisons were made between plants visited by insects, manually pollinated plants (geitonogamy and xenogamy) and plants without pollination induction. Pod set and seed production per plant were determined for each treatment. Among the 8,624 recorded flower-visiting insects, Hymenoptera representatives were the most prevalent (92.3%), among which 99.8% were A. mellifera. The correlation between these bees and blooming progression was positive (r = 0.87; p = 0.002). Pollination induction increased seed productivity from 28.4% (autogamy) to 50.4% with insect visitations, as well as to 48.7 (geitonogamy) and to 55.1% (xenogamy) through manual pollination.
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Barda, Myrto, Filitsa Karamaouna, Vaya Kati e Dionysios Perdikis. "Do Patches of Flowering Plants Enhance Insect Pollinators in Apple Orchards?" Insects 14, n. 2 (19 febbraio 2023): 208. http://dx.doi.org/10.3390/insects14020208.
Testo completoAbstract (sommario):
Apples depend on insect pollination but intensification of agriculture jeopardizes pollination services in agroecosystems. Concerns about the dependency of crop pollination exclusively on honey bees increase the interest in agricultural practices that safeguard wild pollinators in agroecosystems. The purpose of the study was to assess the potential of floral resource provision in apple orchards to enhance the conservation of hymenopterous pollinating insects and potentially the pollination service to the crop. For this reason, flowering plant mixtures sown in patches inside apple orchards were tested against wild plant patches. Pollinator taxa recorded on the sown and wild plant patches were honey bees, wild bees (Andrena, Anthophora, Eucera, Halictus, Lasioglossum, Megachilidae on both; Systropha only on wild plants; Bombus, Hylaeus, Sphecodes, Nomada, Xylocopa only on sown mixture), syrphids, bee flies. The most abundant pollinator of apple was A. mellifera but wild bees were also recorded (Andrena, Anthophora, Bombus, Xylocopa, Lasioglossum, Megachilidae). The sown mixture attracted a more diverse taxa of pollinators and in greater numbers compared to the weed flora, but it did not have an effect on pollinators visiting apple flowers. Groundcover management with patches of suitable flowering mixtures can enhance pollinator conservation in apple orchards.
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Thalwitzer, Liezl, Dave Kelly, Rob D. Smissen, Ruth Butler, David M. Suckling e Ashraf El-Sayed. "Species-specific male pollinators found for three native New Zealand greenhood orchids (Pterostylis spp.) suggest pollination by sexual deception". Australian Journal of Botany 66, n. 3 (2018): 243. http://dx.doi.org/10.1071/bt17111.
Testo completoAbstract (sommario):
Many orchids achieve pollination by deceptive means. Sexually deceptive orchids are pollinated by male insects, which are lured to flowers that mimic the sex pheromones and/or appearance of their female conspecifics. This specialised pollination strategy was recently confirmed for the first time in a Pterostylis species in Australia. We investigated whether this pollination strategy may also be operating in Pterostylis species in New Zealand where generalised plant–insect pollination strategies are most commonly documented. The breeding systems of Pterostylis oliveri Petrie and Pterostylis irsoniana Hatch were investigated in the field with pollination treatments. Sticky traps were set up over flowering P. oliveri, P. irsoniana and Pterostylis venosa Colenso to catch potential pollinators of the flowers. Insects caught carrying orchid pollinia were identified, and the pollinia were identified to plant species with nuclear rDNA internal transcribed spacer (nrDNA ITS) sequences. Both P. oliveri and P. irsoniana were found to be self-compatible, but dependent on insects for pollination. Pollinia from each of the three Pterostylis spp. were found to be carried species-specifically by male fungus gnats (Diptera: Mycetophilidae): only Mycetophila latifascia fungus gnats carried the pollinia of P. oliveri, Morganiella fusca gnats carried the pollinia of P. irsoniana, and Tetragoneura sp. carried the pollinia of P. venosa. The pollinator specificity indicates that each of the male fungus gnat species was attracted to the flowers of a specific Pterostylis orchid. This strongly suggests that each of the orchid species emit a specific floral volatile, most probably resembling the sex pheromones of the female conspecifics, to lure their male pollinators. These are the first documented cases of highly specialised sexually deceptive pollination in New Zealand orchids, which were thought to be predominantly self-pollinating.
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Tarigan, Rasiska, Susilawati Barus, Rina C. Hutabarat, Perdinanta Sembiring, Dorkas Parhusip, Bagus Kukuh Udiarto e Dewi Sartika Aryani. "Keanekaragaman dan aktivitas serangga pengunjung pada bunga wortel". Jurnal Entomologi Indonesia 19, n. 3 (7 dicembre 2022): 214–22. http://dx.doi.org/10.5994/jei.19.3.214.
Testo completoAbstract (sommario):
Pollinating insects act as agents for transferring pollen to the pistil that leads to the increase of quality seed production. Since carrot is propagation through seed, insect pollination are important in the reproduction of the crop. The purpose of this study was to observe the diversity and activity of pollinating insects on carrot flowers in the Experimental Garden of the Agricultural Technology Research and Assessment Installation (IP2TP) Berastagi. Scan sampling method was applied to record the pollinator diversity, while the foraging behaviour of the insects was observed using focal sampling. The number of insects were recorded, collected and preserved in ethanol 70%. Insect identification guideline book was used to identify the insects by comparing their morphology and physiology. The results showed that there were 8 insect species visiting the carrot flowers: Amegilla sp., Polyrachis sp., Coccinella sp., Rhagonycha sp., Muscidae sp., Chrysomya sp., Nephrotoma sp. and Tabanus sp. Amegilla sp. was found to have the highest intensity visiting the carrot flowers (21.6 ± 10.06)% while the lowest was demonstrated by Polyrachis sp. (12.6 ± 4.12)%. Also, Amegilla sp. was recorded to be the most active insect (11.84 ± 1.46 seconds/flower) with the number of flowers visited was 5,06 ± 1,46 flowers/minute. Polyrachis sp. has been revealed to have the longest stay on the flowers visited (49.24 ± 3.89 seconds/flower) with the number of flowers visited 1.21 ± 3.90 flowers/minute. The diversity of pollinating insect was found to be in intermediate level (H’ = 1.89).
21
Scaven, Victoria L., e Nicole E. Rafferty. "Physiological effects of climate warming on flowering plants and insect pollinators and potential consequences for their interactions". Current Zoology 59, n. 3 (1 giugno 2013): 418–26. http://dx.doi.org/10.1093/czoolo/59.3.418.
Testo completoAbstract (sommario):
Abstract Growing concern about the influence of climate change on flowering plants, pollinators, and the mutualistic interactions between them has led to a recent surge in research. Much of this research has addressed the consequences of warming for phenological and distributional shifts. In contrast, relatively little is known about the physiological responses of plants and insect pollinators to climate warming and, in particular, how these responses might affect plant-pollinator interactions. Here, we summarize the direct physiological effects of temperature on flowering plants and pollinating insects to highlight ways in which plant and pollinator responses could affect floral resources for pollinators, and pollination success for plants, respectively. We also consider the overall effects of these responses on plant-pollinator interaction networks. Plant responses to warming, which include altered flower, nectar, and pollen production, could modify floral resource availability and reproductive output of pollinating insects. Similarly, pollinator responses, such as altered foraging activity, body size, and life span, could affect patterns of pollen flow and pollination success of flowering plants. As a result, network structure could be altered as interactions are gained and lost, weakened and strengthened, even without the gain or loss of species or temporal overlap. Future research that addresses not only how plant and pollinator physiology are affected by warming but also how responses scale up to affect interactions and networks should allow us to better understand and predict the effects of climate change on this important ecosystem service.
22
BAĞRIAÇIK, Nil. "Pollinator Insects and Global Pollination Crisis". Journal of the Institute of Science and Technology 7, n. 4 (27 novembre 2017): 37–41. http://dx.doi.org/10.21597/jist.2017.195.
Testo completo
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Elisante, Filemon, Patrick Ndakidemi, Sarah E. J. Arnold, Steven R. Belmain, Geoff M. Gurr, Iain Darbyshire, Gang Xie e Philip C. Stevenson. "Insect pollination is important in a smallholder bean farming system". PeerJ 8 (20 ottobre 2020): e10102. http://dx.doi.org/10.7717/peerj.10102.
Testo completoAbstract (sommario):
Background Many crops are dependent on pollination by insects. Habitat management in agricultural landscapes can support pollinator services and even augment crop production. Common bean (Phaseolus vulgaris L.) is an important legume for the livelihoods of smallholder farmers in many low-income countries, particularly so in East Africa. While this crop is autogamous, it is frequently visited by pollinating insects that could improve yields. However, the value of pollination services to common beans (Kariasii) yield is not known. Methods We carried out pollinator-exclusion experiments to determine the contribution of insect pollinators to bean yields. We also carried out a fluorescent-dye experiment to evaluate the role of field margins as refuge for flower-visitors. Results Significantly higher yields, based on pods per plant and seeds per pod, were recorded from open-pollinated and hand-pollinated flowers compared to plants from which pollinators had been excluded indicating that flower visitors contribute significantly to bean yields. Similarly, open and hand-pollinated plants recorded the highest mean seed weight. Extrapolation of yield data to field scale indicated a potential increase per hectare from 681 kg in self-pollinated beans to 1,478 kg in open-pollinated beans indicating that flower visitors contributed significantly to crop yield of beans. Our marking study indicated that flower-visiting insects including bees, flies and lepidopterans moved from the field margin flowers into the bean crop. Overall, these results show that insect pollinators are important for optimising bean yields and an important food security consideration on smallholder farms. Field margin vegetation also provides habitat for flower-visiting insects that pollinate beans. Hence, non-crop habitats merit further research focusing on establishing which field margin species are most important and their capacity to support other ecosystem services such as natural pest regulation or even pests.
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Luo, Shi-Xiao, Lian-Jie Zhang, Shuai Yuan, Zhong-Hui Ma, Dian-Xiang Zhang e Susanne S. Renner. "The largest early-diverging angiosperm family is mostly pollinated by ovipositing insects and so are most surviving lineages of early angiosperms". Proceedings of the Royal Society B: Biological Sciences 285, n. 1870 (3 gennaio 2018): 20172365. http://dx.doi.org/10.1098/rspb.2017.2365.
Testo completoAbstract (sommario):
Insect pollination in basal angiosperms is assumed to mostly involve ‘generalized' insects looking for food, but direct observations of ANITA grade (283 species) pollinators are sparse. We present new data for numerous Schisandraceae, the largest ANITA family, from fieldwork, nocturnal filming, electron microscopy, barcoding and molecular clocks to infer pollinator/plant interactions over multiple years at sites throughout China to test the extent of pollinator specificity. Schisandraceae are pollinated by nocturnal gall midges that lay eggs in the flowers and whose larvae then feed on floral exudates. At least three Schisandraceae have shifted to beetle pollination. Pollination by a single midge species predominates, but one species was pollinated by different species at three locations and one by two at the same location. Based on molecular clocks, gall midges and Schisandraceae may have interacted since at least the Early Miocene. Combining these findings with a review of all published ANITA pollination data shows that ovipositing flies are the most common pollinators of living representatives of the ANITA grade. Compared to food reward-based pollination, oviposition-based systems are less wasteful of plant gametes because (i) none are eaten and (ii) female insects with herbivorous larvae reliably visit conspecific flowers.
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Mandal, Eeshita, Md Ruhul Amin, Habibur Rahman e Abdul Mannan Akanda. "Abundance and foraging behavior of native insect pollinators and their effect on mustard (Brassica juncea L.)". Bangladesh Journal of Zoology 46, n. 2 (1 dicembre 2018): 117–23. http://dx.doi.org/10.3329/bjz.v46i2.39045.
Testo completoAbstract (sommario):
A field experiment was carried out in Gazipur, Bangladesh to find out the abundance and behavior of native insect pollinators and their impact on the yield and seed quality of mustard (Brassica juncea L.). Total 8 species of insects under 8 different families in 3 orders were found as pollinator and their abundance ranged from 0.5 to 6.6/30 sweeps. The pollinator insects revealed statistically higher abundance compared to pest, predator and other category. The pollinators were most abundant at 11.0 hrs of the day and differed in their landing duration on flower. Ant and cabbage butterfly stayed statistically similar and longer time (24.1 and 23.5 sec., respectively). The highest yield (994.3 kg/ha) was obtained from insect managed pollination treatment followed by open (759.7 kg/ha) and enclosed condition (272.3 kg/ha). Insect pollination revealed higher percentage of germination, t100-seed weight, per cent oil and protein content but the results did not differ statistically.
Bangladesh J. Zool. 46(2): 117-123, 2018
26
Sharma, Manju V., e Kundaranahalli R. Shivanna. "Pollinators, pollination efficiency and fruiting success in a wild nutmeg, Myristica dactyloides". Journal of Tropical Ecology 27, n. 4 (31 maggio 2011): 405–12. http://dx.doi.org/10.1017/s0266467411000174.
Testo completoAbstract (sommario):
Abstract:We investigated the pollinator assemblage in Myristica dactyloides, a dioecious tree species occupying the intermediate canopy stratum of the mid- and high-elevation wet evergreen forests and endemic to Sri Lanka and the Western Ghats of India. We surveyed two populations and, in one of them, marked four male and three female trees for observations on floral display and insect foraging, and two female trees for experimental pollination. Yellow sticky traps were used to sample insects in the canopy during the flowering season of December 2007 in addition to direct observations of insect activity in 2006. Myristicaceae members from other tropical areas have been reported to be specialized to beetle pollination, but our observations provide evidence of a generalist pollination system in M. dactyloides, composed of small, diverse insects: thysanopterans (thrips), coleopterans (beetles), halictid bees and dipterans (syrphid and phorid flies). Quantifying floral display, we found that female inflorescences were smaller, offered no reward and attracted significantly fewer pollinators in comparison to male inflorescences. Fruit set was low and could be attributed to a 29% flower abscission and abortion of young fruits, but a reasonably high natural pollination efficiency combined with pollination experiments established that there was no pollination limitation in the study population.
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Thapa, RB. "Honeybees and other Insect Pollinators of Cultivated Plants: A Review". Journal of the Institute of Agriculture and Animal Science 27 (1 maggio 2006): 1–23. http://dx.doi.org/10.3126/jiaas.v27i0.691.
Testo completoAbstract (sommario):
Insects are viewed from the harmful perspectives and aimed at killing them through several means including indiscriminate use of deadly chemicals. If good judgment made keeping views on sustainable crop production, natural balance and pollution free environment, they are important component of the ecosystem and their beneficial aspects are immense. One of them is that insects provide pollination service to plants. The study showed that over 50 species of insects visited flowers of 17 different species of selected crops during flowering periods. The visiting preferences of insects to flowers of different crops differed among the crop species and insect species as well. In fact, of the total pollination activities, over 80% is performed by insects and bees contribute nearly 80% of the total insect pollination, and therefore, they are considered the best pollinators. The manmade agro-ecosystem exerted pressure and forced to decline pollinators and their diversity, which resulted in reduced agricultural productivity again threatening biodiversity. Management of wide diversities of honeybees and other beneficial insects and flowering plant species occurring in Nepal help to maintain diversity of flora and bee fauna, pollination and reward hive products in the service of mankind. This paper covers honeybees and other insect species visiting various crop flowers.
Key words : Pollination, honeybees, insect, flower visitors
J. Inst. Agric. Anim. Sci. 27:1-23 (2006)
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Oriani, Aline, Paulo T. Sano e Vera L. Scatena. "Pollination biology of Syngonanthus elegans (Eriocaulaceae - Poales)". Australian Journal of Botany 57, n. 2 (2009): 94. http://dx.doi.org/10.1071/bt08119.
Testo completoAbstract (sommario):
Studies on the pollination biology of Eriocaulaceae are scarce although particularly interesting because of its inclusion in the Poales, a predominantly wind-pollinated order. The pollination biology of Syngonanthus elegans (Bong.) Ruhland was studied during two annual flowering periods to test the hypothesis that insect pollination was its primary pollination system. A field study was carried out, including observations of the morphology and biology of the flowers, insect visits and pollinator behaviour. We also evaluated seed set, seed germination and seedling development for different pollination modes. Although seeds were produced by self-pollination, pollination by small insects contributed most effectively to the reproductive success of S. elegans, resulting in the greatest seed set, with the highest germination percentage and optimum seedling vigour. The floral resources used by flower visitors were pollen and nectar that was produced by staminate and pistillate flowers. Self-pollination played a minor role and its consequence was inbreeding depression.
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Prabowo, Muhammad Amin, Tris Haris Ramadhan e Edi Syahputra. "POPULASI ELAEDOBIUS KAMERUNICUS PADA TANAMAN KELAPA SAWIT YANG BERBEDA UMUR DI KECAMATAN RASAU JAYA, KABUPATEN KUBU RAYA". Perkebunan dan Lahan Tropika 11, n. 2 (1 dicembre 2021): 90. http://dx.doi.org/10.26418/plt.v11i2.61202.
Testo completoAbstract (sommario):
Pollination in oil palm is generally carried out by insects. The beetle Elaeidobius kamerunicus is one of the effective pollinating insects for oil palm. This beetle breeds well on male flowers, this beetle can also reach female flowers located in the inner bunch, so this condition causes more perfect pollination. This study aims to determine the population of oil palm pollinating insects E. kamerunicus at several ages of oil palm plants which will be associated with environmental factors and ways of oil palm cultivation, both application of pesticides and fertilizers in Rasau Jaya District, Kubu Raya Regency. Insect sampling in this study used a purposive sampling method (determined sample), which used 3 plant blocks with different age groups of 4, 6, and 9 years respectively. The method used is the observation method, namely observing the population of oil palm pollinating insects directly on oil palm flowers. Observations were made on the population of E. kamerunicus by counting the number of E. kamerunicus visiting blooming oil palm flowers obtained from yellow sticky traps with a size of 20x30 cm placed near oil palm flowers. The results of the study concluded that the older the age of the oil palm plant, the greater the number of spikelets and the population of E. kamerunicus insects increased.
30
Mahy, Grégory, Jacques De Sloover e Anne-Laure Jacquemart. "The generalist pollination system and reproductive success of Calluna vulgaris in the Upper Ardenne". Canadian Journal of Botany 76, n. 11 (1 novembre 1998): 1843–51. http://dx.doi.org/10.1139/b98-133.
Testo completoAbstract (sommario):
Although specialist pollination systems are often thought to be the outcome of selection, wide evidence exists for generalization within plant-pollinator interactions. We studied the pollination system and reproductive success of Calluna vulgaris (L.) Hull over 3 years in an Upper Ardennes site in Belgium. A wide variety of insect visitors was recorded including Hymenoptera, Diptera, and Lepidoptera. Relative abundance of families and species of visitors varied markedly among years except for bees. Bumblebees and honeybees were the most efficient pollinators at the study site. Syrphid flies, mainly large ones, acted as important co-pollinators because of their high relative frequency. Calluna pollen was also dispersed by wind, and insect-exclusion experiments demonstrated that wind pollination contributed to reproductive success. Following open pollination, fruit set was high, ranging from 82.0 to 97.2% and independent of sampling location. Mean seed number per fruit was less than maximum potential seed number and varied strongly among sampling locations. We discuss this pollination system (generalist insect and wind) in terms of the ecological and geographical success of the species.Key words: Calluna vulgaris, pollinator visitation, insects, wind pollination, reproductive success.
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Cook, Brynn, Alexander Haverkamp, Bill S. Hansson, T’ai Roulston, Manuel Lerdau e Markus Knaden. "Pollination in the Anthropocene: a Moth Can Learn Ozone-Altered Floral Blends". Journal of Chemical Ecology 46, n. 10 (2 settembre 2020): 987–96. http://dx.doi.org/10.1007/s10886-020-01211-4.
Testo completoAbstract (sommario):
Abstract Insect pollination is essential to many unmanaged and agricultural systems and as such is a key element in food production. However, floral scents that pollinating insects rely on to locate host plants may be altered by atmospheric oxidants, such as ozone, potentially making these cues less attractive or unrecognizable to foraging insects and decreasing pollinator efficacy. We demonstrate that levels of tropospheric ozone commonly found in many rural areas are sufficient to disrupt the innate attraction of the tobacco hawkmoth Manduca sexta to the odor of one of its preferred flowers, Nicotiana alata. However, we further find that visual navigation together with associative learning can offset this disruption. Foraging moths that initially find an ozone-altered floral scent unattractive can target an artificial flower using visual cues and associate the ozone-altered floral blend with a nectar reward. The ability to learn ozone-altered floral odors may enable pollinators to maintain communication with their co-evolutionary partners and reduce the negative impacts that anthropogenically elevated oxidants may have on plant-pollinator systems.
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Otieno, Mark, Neelendra Joshi e Benjamin Rutschmann. "Flower visitors of Streptocarpus teitensis: implications for conservation of a critically endangered African violet species in Kenya". PeerJ 9 (26 gennaio 2021): e10473. http://dx.doi.org/10.7717/peerj.10473.
Testo completoAbstract (sommario):
Background The African violets are endangered plant species restricted mainly to the Eastern Arc Mountains biodiversity hotspots in Kenya and Tanzania. These plants grow well in shaded environments with high humidity. Given their restricted geographical range and published evidence of dependance on insect vectors to facilitate sexual reproduction, understanding their pollination biology is vital for their survival. Methods We conducted an empirical study using flower visitor observations, pan trapping and bagging experiments to establish the role of flower visitors in the fruit set of a locally endemic and critically endangered species of African violet in Taita Hills, Kenya, Streptocarpus teitensis. Results The study found that fruit set is increased by 47.8% in S. teitensis when flowers are visited by insects. However, it is important to note the presence of putative autogamy suggesting S. teitensis could have a mixed breeding system involving self-pollination and cross-pollination since bagged flowers produced 26.9% fruit set. Conclusions Insects appear to be essential flower visitors necessary for increased fruit set in S. teitensis. However, there is evidence of a mixed breeding system involving putative self-pollination and cross-pollination suggesting that S. teitensis is somewhat shielded from the negative effects of pollinator losses. Consequently, S. teitensis appears to be protected to a degree from the risks such as reproduction failure associated with pollinator losses by the presence of a safety net in putative self-pollination.
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Rydin, Catarina, e Kristina Bolinder. "Moonlight pollination in the gymnosperm Ephedra (Gnetales)". Biology Letters 11, n. 4 (aprile 2015): 20140993. http://dx.doi.org/10.1098/rsbl.2014.0993.
Testo completoAbstract (sommario):
Most gymnosperms are wind-pollinated, but some are insect-pollinated, and in Ephedra (Gnetales), both wind pollination and insect pollination occur. Little is, however, known about mechanisms and evolution of pollination syndromes in gymnosperms. Based on four seasons of field studies, we show an unexpected correlation between pollination and the phases of the moon in one of our studied species, Ephedra foeminea . It is pollinated by dipterans and lepidopterans, most of them nocturnal, and its pollination coincides with the full moon of July. This may be adaptive in two ways. Many nocturnal insects navigate using the moon. Further, the spectacular reflection of the full-moonlight in the pollination drops is the only apparent means of nocturnal attraction of insects in these plants. In the sympatric but wind-pollinated Ephedra distachya , pollination is not correlated to the full moon but occurs at approximately the same dates every year. The lunar correlation has probably been lost in most species of Ephedra subsequent an evolutionary shift to wind pollination in the clade. When the services of insects are no longer needed for successful pollination, the adaptive value of correlating pollination with the full moon is lost, and conceivably also the trait.
34
Larcenaire, Craig, Fumin Wang, Ida Holásková, Richard Turcotte, Michael Gutensohn e Yong-Lak Park. "Characterization of the Insect Assemblage and Associated Floral Volatiles of Black Cherry (Prunus serotina)". Plants 10, n. 10 (15 ottobre 2021): 2195. http://dx.doi.org/10.3390/plants10102195.
Testo completoAbstract (sommario):
Black cherry is an ecologically important high-value wood. A decline of its regeneration has been reported in the USA, which could be associated with a lack of pollination. This study was conducted to identify insects visiting black cherry flowers, to determine whether insects captured on the flowers carry black cherry pollen and to identify the volatile organic compounds (VOCs) emitted by flowers of black cherry. A two-year insect survey was conducted before, during and after the black cherry bloom. A total of 9533 insects were captured in traps and Diptera was the most abundant (64.1%). Significantly more insects in Diptera, Lepidoptera and Thysanoptera were captured in the traps installed in the canopy than those on the ground, and Anthalia bulbosa (Diptera: Hybotidae) was the dominant species. Electron microscopy analyses demonstrated that insects captured in the canopy indeed carried black cherry pollen. Black cherry flowers emitted a VOC blend that is composed of 34 compounds and dominated by β-ocimene and several phenylpropanoids/benzenoids. This floral VOC profile is similar to that of other pollinator-dependent Prunus species. This study reports pollinator insects and associated VOCs, for the first time, that could play a significant role in the pollination and regeneration of black cherry.
35
Goodman, RD, e BP Oldroyd. "Honeybee pollination of strawberries (Fragaria x ananassa Duchesne)". Australian Journal of Experimental Agriculture 28, n. 3 (1988): 435. http://dx.doi.org/10.1071/ea9880435.
Testo completoAbstract (sommario):
The pollination requirements of strawberries (Fragaria x ananassa Duchesne cv. Tioga) were examined in a planting in southern Victoria. Plots that were accessible to honeybees (Apis mellifera L.) had 20.8% marketable berries (well shaped, > 10 g fresh weight), whereas plots that were not accessible had only 4.5% marketable berries. The total numbers of fruit (marketable and unmarketable) were not affected by the presence of pollinating insects. Honeybees were considered to be the main pollinators of this crop. They comprised 58.9% of insect visitors to the flowers. The behaviour patterns of other insects were such that they would effect little or no pollination. We conclude that the presence of an adequate population of honeybees increases the proportion of well shaped (marketable) berries.
36
Krakos, Kyra N., Gary M. Booth e Peter Bernhardt. "Mechanical vs. Beetle-mediated Self-pollination in Gossypium Tomentosum (Malvaceae), an Endangered Shrub". International Journal of Insect Science 2 (gennaio 2010): IJIS.S4801. http://dx.doi.org/10.4137/ijis.s4801.
Testo completoAbstract (sommario):
Experimental hand pollinations of the endangered, Hawaiian, endemic, Gossypium tomentosum Nutt. Ex. (Malvaceae) showed that it was self-compatible, but self-pollination resulted in reduced reproductive output. Field observations and pollen tube analyses using fluorescence microscopy showed that mechanical self-pollination in this species included a mechanism known as bending stigmas. A receptive stigma bent backwards and contacted dehiscent anthers in 7% of flowers found on 17 G. tomentosum plants. The yellow flowers were nectarless and were not visited by most anthophilous insects in situ except for the introduced, nitidulid beetle, Aethina concolor Macleay. Collections and insect GI-tract dissections showed that A. concolor carried and ate the pollen of the host flower. Field observations recorded regular contact between beetles and stigma lobes as these insects exited the flowers effecting self-pollination. Behavioral experiments showed that the beetles responded positively to a yellow visual cue. Under some circumstances, an introduced pollen vector may help maintain a low level of reproductive success in an insular endemic.
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Tamburini, Giovanni, Francesco Lami e Lorenzo Marini. "Pollination benefits are maximized at intermediate nutrient levels". Proceedings of the Royal Society B: Biological Sciences 284, n. 1860 (9 agosto 2017): 20170729. http://dx.doi.org/10.1098/rspb.2017.0729.
Testo completoAbstract (sommario):
Yield production in flowering crops depends on both nutrient availability and pollination, but their relative roles and potential interactions are poorly understood. We measured pollination benefits to yield in sunflower, combining a gradient in insect pollination (0, 25, 50, 100%) with a continuous gradient in nitrogen (N) fertilization (from 0 to 150 kg N ha −1 ) in an experiment under realistic soil field conditions. We found that pollination benefits to yield were maximized at intermediate levels of N availability, bolstering yield by approximately 25% compared with complete pollinator exclusion. Interestingly, we found little decrease in yield when insect visits were reduced by 50%, indicating that the incremental contribution of pollination by insects to yield is greater when the baseline pollination service provision is very low. Our findings provide strong evidence for interactive, nonlinear effects of pollination and resource availability on seed production. Our results support ecological intensification as a promising strategy for sustainable management of agroecosystems. In particular, we found optimal level of pollination to potentially compensate for lower N applications.
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Nakonechnaya, Olga V., Olga G. Koren, Vasilii S. Sidorenko, Sergey A. Shabalin, Tatyana O. Markova e Alexander V. Kalachev. "Poor fruit set due to lack of pollinators in Aristolochia manshuriensis (Aristolochiaceae)". Plant Ecology and Evolution 154, n. 1 (23 marzo 2021): 39–48. http://dx.doi.org/10.5091/plecevo.2021.1747.
Testo completoAbstract (sommario):
Background and aims – Interactions of insects with trap flowers of Aristolochia manshuriensis, a relic woody liana with fragmented natural populations from south-eastern Russia, were studied. Pollination experiments were conducted to identify the causes of the poor fruit set in this plant.Material and methods – The study was carried out at two ex situ sites within the natural range of A. manshuriensis in the suburban zone of the city of Vladivostok (Russia). The floral morphology was examined to verify how it may affect the process of pollination in this species. To test for a probability of self-pollination, randomly selected flowers at the female phase of anthesis (day 1 of limb opening) were hand-pollinated with pollen from the same plant. The daily insect visitation was studied. The pollen limitation coefficient and the number of visitors to the flowers were determined. To identify insects that lay eggs on the flowers, the insects were reared from eggs collected from fallen flowers. Both caught and reared insects were identified.Key results – The floral morphology and the colour pattern of A. manshuriensis are adapted to temporarily trap insects of a certain size. The hand-pollination experiment showed that flowers of this plant are capable of self-pollination by geitonogamy and require a pollinator for successful pollination. The positive value (2.64) for the pollen limitation coefficient indicates a higher fruit set after hand-pollination compared to the control without pollination. The number of visitors to the flowers was low (0.17 visitors per flower per day). Insects from three orders were observed on the flowers: Diptera (up to 90.9%), Coleoptera (8.3%), and Hymenoptera (0.8%). Four species of flies (Scaptomyza pallida, Drosophila transversa (Drosophilidae), Botanophila fugax, and Botanophila sp. 1 (Anthomyiidae)) are capable of transferring up to 2500–4000 pollen grains on their bodies and can be considered as pollinators of A. manshuriensis. Data of the rearing experiment indicate that flies of the families Drosophilidae (S. pallida, D. transversa), Chloropidae (Elachiptera tuberculifera, E. sibirica, and Conioscinella divitis), and Anthomyiidae (B. fugax, B. sp. 1) use A. manshuriensis flowers to lay eggs. Beetles were also collected from the flowers, but they were probably not involved in pollination, because no pollen grains were observed on them during our study.Conclusions – Pollinators of A. manshuriensis include mainly Diptera that lay eggs on the flowers. The poor fruit set (2%) in A. manshuriensis is associated with pollen limitation due to the lack of pollinators, as the number of visitors to flowers was extremely low. This may be due to the fact that the flowers of this species are highly specialized on insects of a certain size for pollination.
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Robinson, Richard W. "Breeding Tomatoes for Attractiveness to Pollinating Insects". HortScience 30, n. 4 (luglio 1995): 797C—797. http://dx.doi.org/10.21273/hortsci.30.4.797c.
Testo completoAbstract (sommario):
Bumblebees are commercially used to improve fruit set of greenhouse tomatoes, but they seldom pollinate tomatoes outdoors if not confined in a no-choice situation. Bumblebees frequently pollinated L. peruvianum and other self-incompatible (SI) Lycopersicon species, but not tomato plants, in the field at Geneva, N.Y. Bumblebees were very efficient pollinators of Sl Lycopersicon species, averaging only 5 s to pollinate one flower and fly to the next. Transfer of this attractiveness to pollinating insects to the tomato could improve fruit set of tomatoes grown in greenhouses with introduced bumblebees. It could also improve fruit set in the field, especially when conditions are poor for pollination. It has potential use for producing F1 hybrid seed, but associated problems make hybrid tomato seed production by insect pollination impractical now. Attractiveness to pollinating insects is being introgressed from L. peruvianum, L. hirsutum, and L. pennellii in the tomato breeding program at Geneva, N.Y. Several floral characteristics were found to be of importance for attracting pollinators, including the reaction to ultraviolet light. Flowers of SI species absorbed UV, whereas tomato flowers reflected UV light.
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Dorin, Alan, Tim Taylor e Adrian G. Dyer. "Goldilocks’ quarter-hectare urban farm: An agent-based model for improved pollination of community gardens and small-holder farms". PLOS Sustainability and Transformation 1, n. 7 (15 luglio 2022): e0000021. http://dx.doi.org/10.1371/journal.pstr.0000021.
Testo completoAbstract (sommario):
Industrial agriculture’s expansive monocultures contrast against community farms of diverse crops in small allotments constrained by urban regulations. These human-controlled differences in scale, arrangement and crop diversity, may differently impact insect foraging and pollination. The relationship between human management and insect pollination is under-explored, especially regarding the implications of insect flower constancy–the tendency of insects to favour visits to a single rewarding flower species during a foraging bout. Although high flower-constancy is associated with reliable pollen transport, its impact on pollination depends also on planting regimes, the vicinity of neighbouring crops, weeds and wildflowers. This study explores the potential pollination impacts of insect flower constancy, heterospecific pollen transfer, and human-dictated crop patch size, using an agent-based model of insect pollinators foraging from two flowering plant species. Highly constant pollinators were most effective in the smallest patches when heterospecific pollen transfer was an issue. As patch size increased, pollination rates improved overall, but less constant insects produced better pollination rates for intermediate sized areas because they rapidly switched preferences between flower species. As patch size increased further, the influence of flower constancy on pollination rates was reduced. Study results suggest that typical community farms containing small single-crop patches operated by independent growers within an allotment, may be better pollinated if operated collaboratively to increase single-crop patch size. Crop patches needn’t be large homogeneous agricultural monocultures, but neither should they be so small and heterogeneous as to inhibit pollination. We found a “Goldilocks zone” around 11m x 11m to be a good compromise for pollination, regardless of the level of flower constancy in local insects. As climate and human land use increasingly impact insect populations, the relationships between pollination systems, growers and policy makers must be continually examined to safeguard food supplies and native ecosystems.
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Tiusanen, Mikko, Paul D. N. Hebert, Niels Martin Schmidt e Tomas Roslin. "One fly to rule them all—muscid flies are the key pollinators in the Arctic". Proceedings of the Royal Society B: Biological Sciences 283, n. 1839 (28 settembre 2016): 20161271. http://dx.doi.org/10.1098/rspb.2016.1271.
Testo completoAbstract (sommario):
Global change is causing drastic changes in the pollinator communities of the Arctic. While arctic flowers are visited by a wide range of insects, flies in family Muscidae have been proposed as a pollinator group of particular importance. To understand the functional outcome of current changes in pollinator community composition, we examined the role of muscids in the pollination of a key plant species, the mountain avens ( Dryas ). We monitored the seed set of Dryas across 15 sites at Zackenberg, northeast Greenland, and used sticky flower mimics and DNA barcoding to describe the flower-visiting community at each site. To evaluate the consequences of shifts in pollinator phenology under climate change, we compared the flower visitors between the early and the late season. Our approach revealed a diverse community of insects visiting Dryas , including two-thirds of all insect species known from the area. Even against this diverse background, the abundance of muscid flies emerged as a key predictor for seed set in Dryas , whereas overall insect abundance and species richness had little or no effect. With muscid flies as the main drivers of the pollinating function in the High Arctic, a recently observed decline in their abundances offers cause for concern.
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WITHANINGSIH, SUSANTI, CLARISA DITY ANDARI, PARIKESIT PARIKESIT e NURULLIA FITRIANI. "The effect of understory plants on pollinators visitation in coffee plantations: Case study of coffee plantations in West Bandung District, West Java, Indonesia". Biodiversitas Journal of Biological Diversity 19, n. 2 (1 marzo 2018): 554–62. http://dx.doi.org/10.13057/biodiv/d190231.
Testo completoAbstract (sommario):
Withaningsih S, Andari CD, Parikesit, Fitriani N. 2018. The effect of understory plants on pollinators visitation in coffee plantations: Case study of coffee plantations in West Bandung District, West Java, Indonesia. Biodiversitas 19: 554-562. West Java is one of the excellent producers of the most expensive coffee in the world (Kopi Luwak). Coffee (Coffea spp.) is one of the crops that require insect pollination for fruit formation. Coffee production in Indonesia is declining in recent years despite the expansion of coffee cultivation area that increases by 2-5 times. The decline in coffee production has been associated with fewer visitations of pollinator insects. Visitations of pollinator insects can improve the quality and quantity of coffee, mainly from the abundance and diversity of pollinator insect. Abundance and diversity of pollinator insects can be improved by to providing them with flowering plants such as understory plants. This study aimed to prove the effect of the existence of flowering plants on the visitation of pollinator insects. Pollinator insects visiting coffee flowers were observed with an observation method in two observation units. The first unit was the location with understory plants while the second was the location without understory plants. The results showed that the abundance of pollinator insects visiting coffee flowers in unit 1 was significantly (P<0.05) higher than that in unit 2. However, the diversity of pollinator insects between the two locations did not differ significantly (P> 0.05).
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Kevan, Peter G., E. Ann Clark e Vernon G. Thomas. "Insect pollinators and sustainable agriculture". American Journal of Alternative Agriculture 5, n. 1 (marzo 1990): 13–22. http://dx.doi.org/10.1017/s0889189300003179.
Testo completoAbstract (sommario):
AbstractUnderestimation of the pivotal role played by managed and native insect pollinators is a key constraint to the sustainability of contemporary agricultural practices. The economic value of such insects to pollination, seed set, and fruit formation greatly outweighs that suggested by more conventional indices, such as the value of honey and wax produced by honeybees. Although the European honeybee has been widely regarded as the single most important pollinating species, the increasing spread of trachael and Varroa mites and Africanized bees threatens the distribution and magnitude of traditional honeybeekeeping enterprises in North America. A number of other bee and insect pollinators, such as orchard bees, bumblebees, and squash bees, which are not affected by either the mites or the Africanized bees, are considered as likely candidates for management and use in commercial agriculture. An additional role can be played by native or wild pollinators, provided that attention is given to curtailing of population losses caused by both inadvertent insecticide poisoning and habitat destruction. To ensure a reliable source of pollinators, both managed and native, a more comprehensive strategy for management of crop pollination is needed. Elements of this strategy include an increased understanding of the biology and ecology of pollinating insects, as well as providing appropriate nesting habitat, and ensuring the availability of alternative sources of “forage” to sustain populations when the target crops are not in bloom. Examples are discussed to illustrate how private initiatives and changes to public policy can enhance pollinator habitat, and ultimately, agricultural productivity.
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Bożek, Małgorzata. "The Effect of Pollinating Insects on Fruiting of Two Cultivars of Lonicera caerulea L." Journal of Apicultural Science 56, n. 2 (1 dicembre 2012): 5–11. http://dx.doi.org/10.2478/v10289-012-0018-6.
Testo completoAbstract (sommario):
Abstract In 2004 and 2006-2008, a study was conducted on the effect of pollinating insects on the fruit, seed set, and development of two cultivars of blue honeysuckle Lonicera caerulea (Sevast.) Pojark.: "Atut" and "Duet". The experiment was carried out in south-eastern Poland, at the Experimental Farm of the University of Life Sciences in Lublin, Poland. Flowers accessible to pollinating insects throughout the whole flowering period, set fruit at a very high percentage. The study average was 90.57% for "Duet" and 88.08% for "Atut". During self-pollination under isolation, on the other hand, the percentage of fruit-bearing flowers was low. In the case of "Atut" the average was 9.37%, whereas for "Duet" it was 23.85%. Multiple fruits formed from isolated flowers had a 45-50% lower weight, on average, than those developed from flowers accessible to pollinating insects. The pollination mode was found to have a significant effect on the number of seeds produced in the multiple fruit. Flowers which were isolated to prevent insect foraging did develop multiple fruits, characterized by a significantly lower number of seeds. The recent studies confirm that several cultivars should be planted on honeysuckle acreage. The presence of managed pollinators can increase quantity and improve quality of fruit yield in honeysuckle.
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Martins Junior, Edivaldo Rodrigues, Ana Carolina Galindo da Costa, Paulo Milet-Pinheiro, Daniela Navarro, William Wayt Thomas, Ana Maria Giulietti e Isabel Cristina Machado. "Mixed pollination system and floral signals of Paepalanthus (Eriocaulaceae): insects and geitonogamy ensure high reproductive success". Annals of Botany 129, n. 4 (17 gennaio 2022): 473–84. http://dx.doi.org/10.1093/aob/mcac008.
Testo completoAbstract (sommario):
Abstract Background and Aims Eriocaulaceae exhibit a great variety of floral traits associated with insect (e.g. nectariferous structures) and wind pollination (unisexual flowers, exposed sexual organs and small pollen grains), as well as the ‘selfing syndrome’ (small flowers, short distance between stigma and anthers, and temporal overlap of male and female phases). Paepalanthus bifidus, P. subtilis and P. tortilis are related species that differ in form, size and colour of floral structures. We aimed to investigate the pollination and reproductive biology of these three species. Methods We analysed the floral biology, floral visitors, pollinator behaviour, and the contribution of insects, wind and spontaneous geitonogamy to fruit set. We also evaluated the floral colour and scent of the species. Colour reflectance of capitula of each species was measured and plotted in models of insect vision. Floral scent samples were extracted and the compounds were compared to vegetative scent samples. Key Results In all species, the staminate and pistillate flowers are arranged in alternating cycles with a temporal overlap between these phases. Ants were the most frequent floral visitors and were effective pollinators in P. bifidus and P. tortilis, while flies were occasional pollinators in P. tortilis. Floral visitors were not observed in P. subtilis. In all species, fruits were produced by spontaneous geitonogamy, with no evidence of wind pollination. According to the models of insect vision, the colours of the capitula of P. bifidus and P. subtilis are the most inconspicuous for ants and flies. We found no difference between the emission of volatiles of inflorescences and vegetative structures. Conclusions This study suggests that ant pollination might be more widespread in Eriocaulaceae than currently assumed. Furthermore, for small monocarpic plants, mixed mating strategies are most favourable, by ensuring reproduction either by outcrossing when pollinators are abundant or by spontaneous geitonogamy when pollinations are scarce/absent.
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Hayata, Hayata, Nasamsir Nasamsir e Prasetyo Hady Saputro. "Populasi dan Keanekaragaman Serangga Penyerbuk di Kebun Kelapa Sawit Desa Rantau Kapas Bukit Paku Kabupaten Batanghari". Jurnal Media Pertanian 7, n. 2 (21 ottobre 2022): 132. http://dx.doi.org/10.33087/jagro.v7i2.161.
Testo completoAbstract (sommario):
The presence of pollinatting insect is an unseparated part in oil palm cultivation. The insect population and its diversity will affect the pollination process that will produce a good fruit. This study aimed to determine and study the population as well as the species diversity of pollinating insects on smallhoulder oil palm plantations in Rantau Kapas Bukit Paku Village, Batanghari Regency. Unformated Trials was carried out as the experimental design and the location was porpusively chosen because there were plants under study and were uniform in that location.The method used was a descriptive survey method, which deal with observing the types and numbers of pollinating insects caught at the sample locations in smallholder oil palm plantations aged 6 years. Catching pollinating insects used Kairomix pheromone traps. The results of the study showed that there were 18,301 species of E kamerunicus and 478 species of Thrips hawaiiensis pollinated insects were caught, while 378 non-pollinated insects were caught in the oil palm plantation area in the Bukit Paku area. The general morphology of the fruit was Tenera fruit type, with the average of Fresh Fruit Bunch (FFB) weight as 9.4 kg.
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Silveira, Rodrigo Santtanna, Rodrigo Bustos Singer e Viviane Gianluppi Ferro. "Pollination in Epidendrum densiflorum Hook. (Orchidaceae: Laeliinae): Fraudulent Trap-Flowers, Self-Incompatibility, and a Possible New Type of Mimicry". Plants 12, n. 3 (3 febbraio 2023): 679. http://dx.doi.org/10.3390/plants12030679.
Testo completoAbstract (sommario):
The pollination and the breeding system of Epidendrum densiflorum (Orchidaceae: Laeliinae) were studied through fieldwork and controlled pollinations in cultivated plants. Pollination is exclusively promoted by males of diurnal Lepidoptera: five species of Arctiinae and four of Ithomiinae were recorded as pollinators. These male insects are known to obtain alkaloids (through the nectar) in flowers of Asteraceae and Boraginaceae. However, the flowers of E. densiflorum are nectarless, despite presenting a cuniculus (a likely nectariferous cavity). Pollinators insert their proboscides into the flowers and remove or deposit the pollinaria while searching for nectar. The floral tube is very narrow, and insects struggle for up to 75 min to get rid of the flowers. Plants are pollinator-dependent and nearly fully self-incompatible. Pollinarium removal, pollination, and fruiting success (2.85%) were very low; facts that are consistent with the patterns globally observed in deceptive (rewardless) orchids. Nilsson’s male efficiency factor (0.245) was also low, indicating pollen loss in the system. Based on our field observations, we suggest that the fragrance of E. densiflorum likely mimics these plants that are normally used as a source of alkaloids by male Lepidoptera, a hypothesis that we intend to test in the future.
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Mahmoud, Farag. "Insects associated with sesame (Sesamun indicum L.) and the impact of insect pollinators on crop production". Pesticidi i fitomedicina 27, n. 2 (2012): 117–29. http://dx.doi.org/10.2298/pif1202117m.
Testo completoAbstract (sommario):
A survey of insects associated with sesame, Sesamun indicum L. (Pedaliaceae) was conducted at the Agriculture Research Farm of The Faculty of Agriculture, University of Suez Canal during the growing seasons 2010 and 2011. All different insect species found on the experimental site were collected for identification. Sampling was done once a week and three times a day. Three methods were used to collect insects from the sesame plants (a sweep net, pitfall traps, digital camera and eye observation). A total of 31 insect species were collected and properly identified during the survey. Insects recorded on the plants were divided into four groups, true pollinators (Hymenoptera), other pollinators (Diptera, Coleoptera and Lepidoptera), pests (Orthoptera, Odonata, Hemiptera and Homoptera) and natural enemies (Coleoptera, Hymenoptera, Neuroptera and Dictyoptera). For studying the impact of insect pollination on sesame production, the experiment was divided in two: opened and non-opened pollination of sesame. 50 plants from nonopened pollination were covered with a perforated paper bag to allow the air to pass through and to prevent insects from approaching the plants. Quantitative and qualitative parameters were measured as follows: pod weight, number of seeds in each pod, weight of 1000 seeds, germination (%), seedlings vigour and oil content (%). Results clearly demonstrate that the opened pollination improved the crop production.
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Nuortila, Carolin, Juha Tuomi e Kari Laine. "Inter-parent distance affects reproductive success in two clonal dwarf shrubs, Vaccinium myrtillus and Vaccinium vitis-idaea (Ericaceae)". Canadian Journal of Botany 80, n. 8 (1 agosto 2002): 875–84. http://dx.doi.org/10.1139/b02-079.
Testo completoAbstract (sommario):
Clonal propagation and limited dispersal of seeds lead to genetic population structures in which most potential mates are relatives. If the species suffers from inbreeding depression or is self-incompatible, the number of seeds matured per fruit may be limited by the lack of outcrossing by unrelated pollen. We tested for distance-related genetic structure by hand-pollinating plants at increasing distances and measuring fruit set (berries/pollinated flowers) and seed number per fruit in natural populations of bilberry (Vaccinium myrtillus L.) and lingonberry (Vaccinium vitis-idaea L.). Bagging of the flower buds without natural (pollination by insects) or hand-pollination yielded almost no fruit or seed, suggesting that the species are obligately insect pollinated. Self-pollination led to a significant reduction in seed number per fruit and increased seed abortion compared with cross-pollination. Moreover, seed number increased with increasing distance between the pollen donor and pollen recipient. Flight distances of bumblebees were estimated for bilberry by monitoring between-flower and, for lingonberry, between-inflorescence flight distances. About 90% of all flights were at distances of less than 1 m. At this distance, we observed less than the maximum seed number per fruit in hand-pollinations in both study species. Consequently, clonal growth is likely to be an important factor that constrains fruit and seed number in these species.Key words: bumblebee forage distance, clonal, hand-pollination, inter-parent distance, reproductive success, Vaccinium.
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Hall, John A., Gimme H. Walter, Dana M. Bergstrom e Peter Machin. "Pollination ecology of the Australian cycad Lepidozamia peroffskyana (Zamiaceae)". Australian Journal of Botany 52, n. 3 (2004): 333. http://dx.doi.org/10.1071/bt03159.
Testo completoAbstract (sommario):
Experiments carried out to investigate the reproductive ecology of the Australian cycad Lepidozamia peroffskyana (Regal, Bull. Soc. Imp. Nat. Mosc. 1857, 1: 184) revealed that this species is pollinated exclusively by host-specific Tranes weevils (Pascoe 1875). The weevils carry out their life cycle within the tissues of the male cones but also visit the female cones in large numbers. Female cones from which insects (but not wind) was excluded had a pollination rate that was essentially zero. In contrast, female cones from which wind (but not insects) were excluded had a pollination rate comparable with naturally pollinated cones. Assessment of Tranes weevil pollen load indicated that they are effective pollen-carriers. No other potential insect pollinators were observed on cones of L. peroffskyana. Sampling of airborne loads of cycad pollen indicated that wind-dispersed grains were not consistently recorded beyond a 2-m radius surrounding pollen-shedding male cones. The airborne load of cycad pollen in the vicinity of pollination-receptive female cones was minimal, and the spatial distribution of the coning population indicated that receptive female cones did not usually occur close enough to pollen-shedding male cones for airborne transfer of pollen to explain observed natural rates of seed set. These multiple lines of evidence suggest that wind–once considered the only pollination vector for cycads and other gymnosperms–plays only a minimal role in the pollination of L. peroffskyana, if any at all. The global diversity of insects associated with cycads suggests that some lineages of pollinating beetles may have been associated with cycad cones since Mesozoic times.