Open access journal: http://periodicos.uefs.br/ojs/index.php/sociobiology ISSN: 0361-6525 DOI: 10.13102/sociobiology.v67i4.5023Sociobiology 67(4): 593-598 (December, 2020) Pollinator insects in agricultural landscapes are dwindling over the years due to the use of agrochemicals, diseases, land fragmentation and rapid urbanization (Biesmeijer et al., 2006; Potts et al., 2010). The intensive agricultural practices make the pollinators and natural enemies devoid of nectar, pollen, shelter, and nesting sites (Cane 2008, Pywell et al., 2011). The easiest and feasible way for conservation of these pollinators could be the maintenance of flora attractive to pollinators such as small patches of pollinator gardens in urban and farmlands, which support them with food and shelter over time. The consequence of such efforts would be the resulting enhancement of pollination service to our food crops. These gardens not only serve as a reservoir of both pollinators and biological control agents like predators and parasitoids but also help in educating the public and enhancing the aesthetic value of the urban and farm ecosystems (Kells et al., 2001; Sheffield et al., 2008). Planting Abstract Pollinators are important providers of ecosystem services through plant and crop pollination. However, pollinator population/colony decline has raised concern for their conservation in farm lands as well as in urban areas. Given the need for conservation of these pollinators, we developed a pollinator garden at Yelahanka Campus of ICAR-National Bureau of Agricultural Insect Resources in an area of one acre by planting over 50 plant species. Thirty-nine species of bees were documented from the flora of the pollinator garden. Out of the thirty-nine species of bees, nineteen species of bees belong to non-Apis families viz., Megachilidae and Halictidae. Apart from foraging on the flowers, the solitary bees like Megachile sp. were found nesting in the stems, fallen dried flowers in the pollinator garden. The bees were found year-round foraging upon the flora in the pollinator garden. Pollinator garden is a way to provide in-situ conservation of native bees while sustaining the valuable pollination service in various crop plants. Sociobiology An international journal on social insects TM Shivalingaswamy, U Amala, A Gupta, A Raghavendra Article History Edited by Evandro Nascimento Silva, UEFS, Brazil Received 24 February 2020 Initial acceptance 15 October 2020 Final acceptance 26 October 2020 Publication date 28 December 2020 Keywords Bees, Conservation, In-situ, Non-Apis bees, Pollinator garden, Pollen, Shelter. Corresponding author Udayakumar Amala https://orcid.org/0000-0002-2394-259X Scientist (Entomology), Division of Germplasm Conservation and Utilization, ICAR-National Bureau of Agricultural Insect Resources H A Farm Post, PB No 2491, Bengaluru 560024, Karnataka, India. E-Mail: amala.uday@gmail.com diverse flowering plants in the pollinator garden supports both bee diversity and density in addition to the provision of food and nesting sources for the native bees (Kremen et al., 2002). An effort has been made to develop two patches (approximately one-acre area) of pollinator gardens in ICAR- NBAIR-Yelahanka Campus. The campus is spread over 8.5 ha area in the North of Bengaluru city (13° 5’ 48.8724’’ N 77° 33’ 59.7168’’ E). Over 50 species of plants belonging to diverse families (trees, shrubs, herbs and climbers) were brought from a local state recognized scientific nursery and planted during 2012 and nurtured and observed for their flowering and attractiveness to pollinator insects, especially bees. We studied forty-six species of plants in the established pollinator gardens. Observations were made on the visitation of different species of bees at 15 days interval over a period of three years (2013-2015). The bees were collected using sweep nets and killed using ethyl acetate. The killed specimens Division of Germplasm Conservation and Utilization, ICAR-National Bureau of Agricultural Insect Resources, Bengaluru, Karnataka, India Non-Apis bee diversity in an experimental pollinator garden in Bengaluru – a Silicon Valley of India SHORT NOTE TM Shivalingaswamy, U Amala, A Gupta and A Raghavendra – Pollinator garden to conserve diversity of bees594 were relaxed and dry mounted for taxonomic identification. Some of the bee specimens were identified using taxonomic keys and others were identified by experts whose names are acknowledged in this publication elsewhere. The plant species were ranked into different categories based on the number of bee species attracted (Table 1, Fig 2) The reward (nectar or pollen) and other nest building materials collected by each species of the bees were recorded. Thirty-nine species of bees were documented from different species of plants maintained in the pollinator garden (Table 2 & Fig 1). The major plant families attracting the bees in the increasing order of attraction were Lamiaceae (Ocimum basilicum and O. gratissimum), Convolvulaceae (Argyreia cuneata and Jacquemontia violacea), Acanthaceae (Asystasia gangetica), Asteraceae (Gaillardia pulchella), Passifloraceae (Passiflora edulis) and Lythraceae (Woodfordia fruticosa). Fig 1. Diverse species of pollinators observed in the pollinator garden. Argyreia cuneata (Convolvulaceae) was recorded to bloom between April to October, exhibiting attractive purple flowers. The bee activity on this plant was recorded from 0800 hrs to 1500 hrs, between May to October. There was a reduction in its population coinciding with the reduction in the blooming of A. cuneata. Tetralonia (Thygatina) macroceps (Anthophorinae: Apidae) was found to forage only on this species. Another congener, Argyreia nervosa, was found to be visited by Xylocopa sp. (Xylocopinae: Apidae) and Lithurgus sp. (Lithurginae: Megachilidae) but not by Tetralonia. The presence and absence of target flora as a determining factor for bee frequencies was reported by Frankie et al. (2009). This behavior shows the floral constancy of the bees. Tetralonia (Thygatina) sp. was reported to prefer the herbaceous plant A. populifolia (Convolvulaceae) (Inoka et al., 2002). Bees belonging to the genus Thyreus were recorded to frequently visit Asystasia gangetica (Acanthaceae). The tubular flowers present in this plant were found to attract long tongued bees as they have typical landing platform for the bees to rest and collect the reward. Carpenter bees belonging to the genus Xylocopa were found to forage on Calotropis gigantea (Apocynaceae), performing nectar robbing activity, a common behavior of carpenter bees according to Zhang et al. (2007). Woodfordia fruticosa (Lyrthaceae) was found to attract leaf cutting species Megachile anthracina, which was observed employing leaf bits as resources for nest construction. The nectar rich flowers of W. fruticosa were found to be actively foraged upon by the little bees Apis florea and A. cerana. Apis florea was found to build its nest in the branches of W. fruticosa with the ideal proximity of rich nectar source in the Sociobiology 67(4): 593-598 (December, 2020) 595 Fig 2. Ranking of plants based on number of bees visited.   a  b c d e f  g  h  i j  k  l m n o p q r Rank IV: a. Scaveola taccada, b. Adhatoda zeylanica, c. Hedychium coronaria, d. Asclepias curassavica, e. Citharexylum substratum, f. Aristolochia ringens, g. Woodfordia fruticosa, h. Sauropus androgynus, i. Calotropis gigantea, j. Budleja asiática, k. Cestrum diurnum, l. Quisqualis indica, m. Crotolaria retusa, n. Alpinia sp., o. Chrysophyllum cainito, p. Hamelia patens, q. Mansoa Alliacea, r. Clerodendrum infortunatum Fig 2. Ranking of plants based on number of bees visited.  a  b  Rank I : a. Ocimum basilicum, b. Argyreia cuneata a  Rank II : a. Asystasia gangetica, b. Adhatoda zeylanica b  b ca  Rank III : a. Antigonon leptopus, b. Gaillardia pulchella, c. Ruta graveolans TM Shivalingaswamy, U Amala, A Gupta and A Raghavendra – Pollinator garden to conserve diversity of bees596 Table 1. Different plant species in the Pollinator garden along with ranking based on the number of bees visited. Family Plant Species Rank Lamiaceae Ocimum basilicum* Ocimum gratissimum Strobilanthus barbatus Strobilanthus hamiltoniana I Convolvulaceae Argyreia nervosa Argyreia cuneata* Ipomoea pescaprae Jacquemontia violacea I Acanthaceae Adhatoda zeylanica Andrographis paniculata Asystasia gangetica* II Polygonaceae Antigonon leptopus* III Asteraceae Gaillardia pulchella III Passifloraceae Passiflora edulis III Rutaceae Ruta graveolans III Verbenaceae Citharexylum substratum Clerodendrum viscosum* Vitex negundo IV Elaeocarpaceae Elaeocarpus floribundus*Elaeocarpus sphaericus IV Bignoniaceae Mansoa alliacea Tecoma capensis* IV Solanaceae Cestrum diurnum*Cestrum nocturnum IV Zingiberaceae Alpinia calcarata IV Amaranthaceae Alternanthera sessilis IV Aristolochiaceae Aristolochia ringens IV Annonaceae Artabotrys odoratissimus* Cananga odorata IV Apocynaceae Asclepias curassavica IV Plantaginaceae Bacopa moniera IV Scrophulariaceae Budleja asiatica IV Fabaceae Butea monospermaCrotolaria retusa* IV Apocynaceae Calotropis gigantea IV Sapotaceae Chrysophyllum cainito IV Vitaceae Cissus quadrangularis IV Mimosaceae Adenanthera pavonina IV Rubiaceae Hamelia patens IV Zingiberaceae Hedychium coronaria IV Malpighiaceae Hiptage benghalensis IV Lythraceae Lagerstromia indicaWoodfordia fruticosa* IV Oleaceae Nyctanthes arbor-tristes IV Phyllanthaceae Sauropus androgynus IV Goodeniceae Scaevola taccada IV Malpighiaceae Tristellateia australasiae IV Ranking: I- 15-20 species of bees attracted to the plant, II- 10-15, III- 5-10 and IV-0-5 * The plant species which was more attractive compared with other species in the same families flowers of the plant. The flowers of W. fruticosa are a major source of nectar and pollen visited by Apis cerana and A. mellifera in Shiwalik hills (Kaur & Mattu, 2016). The pithy stems of Clerodendrum viscosum (Verbenaceae) was utilized by small carpenter bee, Ceratina hieroglypica for nest building activity. The destructive sampling of C. viscosum revealed the brood nests of the small carpenter bee C. hieroglyphica harbouring its life stages of pollen food. Pithy stems of Caesalpinia pulcherrima after pruning the branches were reported to be natural nesting sites of small carpenter bee, C. binghami (Amala & Shivalingaswamy, 2019). Continuous availability of flowers in the pollinator garden was found to sustain different species of bees from Spring to Summer. Plants like Asystasia sp. (Acanthaceae) and Hamelia patens (Rubiaceae) were found to have long blooming periods supporting the bee fauna with pollen and nectar rewards. Similar observations were recorded by Wojcik et al. (2008) and reported that flowers with long blooming periods sustained different species of bees in a seasonal sequence. The plant Tristellateia australasiae (Malpighiaceae) was found to be foraged upon by little bee A. florea in large numbers. The composite flowers of Gaillardia pulchella (Asteraceae) was found to be foraged by different species of halictid bees viz., Nomia curvipes, Seladonia propinqua in search for pollen. Blue banded bees Amegilla zonata (Anthphorinae: Apidae) and Sweat bees Hoplonomia westwoodi (Nominae: Halictidae) were recorded as some of the buzz pollinators of tomato and eggplant present in the pollinator garden. Six different aromatic plants belonging to the family Lamiaceae were reported to attract and support many species of bees and hover flies (Barbir et al., 2016). Raju (2005) reported that three species of bees viz., Apis cerana indica, Trigona iridipennis and Ceratina simillima visited the flowers of Woodfordia floribunda Salisb. (Lythraceae) for the collection of pollen and nectar. Plants belonging to the family Convolvulaceae viz., Argyreia populifolia, Ipomoea cairica, I. mauritiana and I. pescaprae attracted five species of solitary bees Lithurgus atratus, Lasioglossum halictoides, L. serenum, Systropha tropicalis and Tetralonia sp.1 in Sri Lanka (Karunaratne et al., 2005). The flowers of the family Asteraceae with typical daisy like flower was reported to attract solitary bees, hoverflies, and ‘other’ flower-visiting insects (Rollings & Goulson, 2019). Peters (2014) reported that Trigona fulviventris, Halictids, Ceratina sp and Bombus pullatus visited the flowers of Hamelia patens (Rubiaceae) for pollen and nectar collection. The flowers of plant, Asystasia chelonoides (Acanthaceae) were reported to be visited by four different species of bees viz., Amegilla comberi, A. puttalama, A. scintillans and Apis cerana (Karunaratne et al., 2005). Xylocopa latipes and X. pubescens as a floral visitor and pollinator of Calotropis gigantea and C. procera was reported by Zafar et al. (2018). Holistically, the plants and the flora in the pollinator garden were found to attract a diverse assemblage of bee Sociobiology 67(4): 593-598 (December, 2020) 597 Table 2. Non-Apis bee and scolid wasp species recorded in the pollinator garden. S. No. Bee species Family 1 Amegilla confusa (Smith, 1854) Apidae 2 Amegilla violacea (Lepeletier, 1841) Apidae 3 Amegilla sp. (zonata group): Apidae 4 Apis cerana Fabricius, 1793 Apidae 5 Apis dorsata Fabricius, 1793 Apidae 6 Apis florea Fabricius, 1787 Apidae 7 Braunsapis sp. Halictidae 8 Ceratina binghami Cockerell, 1908 Apidae 9 Ceratina hieroglyphica Smith, 1854 Apidae 10 Ceratina smaragdula (Fabricius, 1787) Apidae 11 Ceratina sp.1 Apidae 12 Ceratina sp.2 Apidae 13 Coelioxys basalis Smith, 1875 Megachilidae 14 Coelioxys confusus Smith, 1854 Megachilidae 15 Coelioxys sp. Megachilidae 16 Hoplonomia westwoodi (Gribodo, 1894) Halictidae 17 Lasioglossum (Ctenonomia) sp. 1 Halictidae 18 Lasioglossum sp. 2 Halictidae 19 Lithurgus atratus Smith, 1853 Megachilidae 20 Megachile anthracina Smith, 1853 Megachilidae 21 Megachile bicolor (Fabricius, 1781) Megachilidae 22 Megachile cephalotes Smith, 1853 Megachilidae 23 Megachile disjuncta (Fabricius, 1781) Megachilidae 24 Megachile lanata (Fabricius, 1775) Megachilidae 25 Megachile sp.1 Megachilidae 26 Megachile sp.2 Megachilidae 27 Nomia curvipes (Fabricius, 1793) Halictidae 28 Pachynomia sp. Halictidae 29 Scolia affinis Guérin-Méneville, 1830 Halictidae 30 Seladonia propinqua (Smith, 1853) Halictidae 31 Seladonia sp. Halictidae 32 Tetralonia (Thygatina) macroceps (Engel & Baker,2006) Apidae 33 Thyreus histrio (Fabricius, 1775) Apidae 34 Thyreus massuri (Radoszkowski, 1893) Apidae 35 Thyreus sp. Apidae 36 Xylocopa aestuans (Linnaeus, 1758) Apidae 37 Xylocopa amethystina (Fabricius, 1793) Apidae 38 Xylocopa latipes (Drury, 1773) Apidae 39 Xylocopa sp. Apidae species belonging to the families Apidae, Megachilidae, and Halictidae. Plants belonging to the family Lamiaceae and Convolvulaceae could be ideally used to conserve native Apis/ non-Apis bees. The concept of pollinator garden is a vital tool to conserve the native pollinators by providing them food source (nectar and pollen) and habitat (nests construction). Pollinator gardens could be encouraged in urban habitats to enhance the aesthetic value, educative tool for school children and finally to sustain the ecosystem services provided by the pollinators. Acknowledgements The authors are thankful to Dr. C. A. Viraktamath, Emeritus Professor, Principal Investigator, ICAR Network Project on Biosystematics, University of Agricultural Sciences, GKVK Bangalore. Dr. K. D. 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