Journal of Threatened Taxa
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PLATINUM The Journal of Threatened Taxa (JoTT) is dedicated to building evidence for conservaton globally by publishing peer-reviewed artcles online OPEN ACCESS every month at a reasonably rapid rate at www.threatenedtaxa.org. All artcles published in JoTT are registered under Creatve Commons Atributon 4.0 Internatonal License unless otherwise mentoned. JoTT allows allows unrestricted use, reproducton, and distributon of artcles in any medium by providing adequate credit to the author(s) and the source of publicaton. Journal of Threatened Taxa Building evidence for conservaton globally www.threatenedtaxa.org ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print) Communication Pollination ecology of three ecologically valuable carpetweed herbs, Mollugo cerviana, M. nudicaulis and M. pentaphylla (Molluginaceae) Maddala Sulakshana & Aluri Jacob Solomon Raju 26 February 2019 | Vol. 11 | No. 3 | Pages: 13334–13349 DOI: 10.11609/jot.3999.11.3.13334-13349 For Focus, Scope, Aims, Policies, and Guidelines visit htps://threatenedtaxa.org/index.php/JoTT/about/editorialPolicies#custom-0 For Artcle Submission Guidelines, visit htps://threatenedtaxa.org/index.php/JoTT/about/submissions#onlineSubmissions For Policies against Scientfc Misconduct, visit htps://threatenedtaxa.org/index.php/JoTT/about/editorialPolicies#custom-2 For reprints, contact <[email protected]> The opinions expressed by the authors do not refect the views of the Journal of Threatened Taxa, Wildlife Informaton Liaison Development Society, Zoo Outreach Organizaton, or any of the partners. The journal, the publisher, the host, and the part- Publisher & Host ners are not responsible for the accuracy of the politcal boundaries shown in the maps by the authors. Partner Member Threatened Taxa Journal of Threatened Taxa | www.threatenedtaxa.org | 26 February 2019 | 11(3): 13334–13349 Pollination ecology of three ecologically valuable Communication carpetweed herbs, Mollugo cerviana, M. nudicaulis and ISSN 0974-7907 (Online) M. pentaphylla (Molluginaceae) ISSN 0974-7893 (Print) Maddala Sulakshana 1 & Aluri Jacob Solomon Raju 2 PLATINUM OPEN ACCESS 1 Department of Botany, 2 Department of Environmental Sciences, Andhra University, Visakhapatnam, Andhra Pradesh 530003, India. 1 [email protected]; [email protected] (corresponding author) Abstract: Mollugo cerviana, M. nudicaulis and M. pentaphylla are annual herbs which usually grow in open dry sandy and sandy/loamy soils, and also occur in moist habitats, especially cultvated lands. The fowers possess fve tepals, functonal stamens and 3-carpelled ovary with several ovules and three stgmas. M. nudicaulis and M. pentaphylla are pollinated by insects. Haplothrips uses the fowers for breeding and feeding, which afects pollinaton. These species have specialized foral structural and functonal behaviours for self-induced and spontaneous autogamy while keeping the optons open for insect pollinaton afer anthesis. They are facultatve autogamous, which is refected in pollen-ovule ratos and natural fruit and seed set rates. Seed dispersal modes include anemochory, ombrohydrochory and hydrochory. The seeds germinate immediately afer their dispersal, and soil moisture is important in rupturing the seed coat. These species are best adapted to survive in open dry habitats as they take advantage of any sign of temporary humidity to complete their life cycle quickly. Keywords: Anemochory, facultatve autogamy, hydrochory, insect-pollinaton, ombrohydrochory, soil binder. DOI: htps://doi.org/10.11609/jot.3999.11.3.13334-13349 Editor: Kannan C.S. Warrier, Insttute of Forest Genetcs and Tree Breeding, Coimbatore, India. Date of publicaton: 26 February 2019 (online & print) Manuscript details: #3999 | Received 04 January 2018 | Final received 06 February 2019 | Finally accepted 12 February 2019 Citaton: Sulakshana, M. & A.J.S. Raju (2019). Pollinaton ecology of three ecologically valuable carpetweed herbs, Mollugo cerviana, M. nudicaulis and M. penta- phylla (Molluginaceae). Journal of Threatened Taxa 11(3): 13334–13349; htps://doi.org/10.11609/jot.3999.11.3.13334-13349 Copyright: © Sulakshana & Raju 2019. Creatve Commons Atributon 4.0 Internatonal License. JoTT allows unrestricted use, reproducton, and distributon of this artcle in any medium by adequate credit to the author(s) and the source of publicaton Funding: Self-funded. Competng interests: The authors declare no competng interests. Author Details: Mrs. M. Sulakshana PhD, has published four research papers on pollinaton ecology. Prof. A.J. Solomon Raju is working in the Department of Environmental Sciences, Andhra University, Visakhapatnam. He is the recipient of several natonal and internatonal awards. He has more than 300 research papers in internatonal and natonal Journals. Author Contributon: Both the authors contributed equally overall. Acknowledgements: We are thankful to Andhra University, Visakhapatnam, for providing the physical facilites. 13334 Pollinaton ecology of Mollugo species Sulakshana & Raju INTRODUCTION MATERIALS AND METHODS Hutchinson (1926) recognized Molluginaceae Wild patches of Mollugo cerviana, M. nudicaulis as distnct from Aizoaceae. Molluginaceae genera and M. pentaphylla growing in open dry and semi-dry previously included in the larger family Aizoaceae have areas of Visakhapatnam and its surroundings (17.6860N been separated and treated under the Molluginaceae in & 83.2180E) were selected for study during March subsequent classifcatons of the Angiosperm Phylogeny 2015–May 2017. Field trips were conducted to record Group (APG) 1998, APG II of 2003, APG III of 2009 and phenological aspects. Ten inforescences which have APG IV of 2016. APG IV classifcaton is the modern not initated fowering on fve plants were tagged and molecular-based system of plant taxonomy for fowering followed to record anthesis schedule and the tming of plants (angiosperms). The genus Mollugo is distributed anther dehiscence. Twenty-fve fresh fowers were used in tropical to warm temperate parts of North and South to record the foral morphological details. Nectar could America, Europe, Africa and Asia. The generic name is not be measured and analyzed due to its secreton in derived from the Latn word “mollis” meaning sof (Short minute quantty which was further depleted by thrips 2002). M. cerviana is natve to India, Sri Lanka, Pakistan during mature bud and fower life. Twenty mature, and Bangladesh (Parvathamma & Shanthamma 2000). but un-dehisced anthers, two anthers each per fower/ M. nudicaulis is distributed throughout tropical Africa plant from ten plants were collected and examined for and Asia (Burrows & Willis 2005). M. cerviana is a C4 pollen output as per the protocol described in Dafni et species, M. nudicaulis C3-C4 species and M. pentaphylla al. (2005). The calculaton of pollen output per fower C3 species; the frst species is distributed in hot arid and pollen-ovule rato was done as per the formulas regions from pantropics to temperate regions while described in Cruden (1977). Ten fowers each from fve the other two species are distributed from pantropical individuals were used to test stgma receptvity. It was and subtropical regions (Christn et al. 2010). These tested with hydrogen peroxide from mature bud stage to three species are valuable in traditonal medicine for fower closure/drop as per Dafni et al. (2005). Seventy treatng diferent diseases and ailments (Parvathamma & inforescences were tagged prior to the initaton of Shanthamma 2000; Rajamanikandan et al. 2011; Sahu et their fowering and followed for three weeks to record al. 2012). fruit and seed set rate in open-pollinatons. The fruit Litle is known about the pollinaton ecology of and seed morphological characteristcs were observed Molluginaceae, where nectar secretng tssue is present in detail to evaluate their adaptatons for dispersal in almost all species. In several genera showy sepals by diferent means. Fields visits were made during or petals have evolved, both of which strongly suggest rainy season to note the aspects of seed germinaton entomophily (Watson & Dallwitz 1992; Kubitzki et and producton of new plants. Based on the tmings al. 1993). Mollugo vertcillata is pollinated by the of maturaton of anthers and receptvity of stgmas, syrphid fy Mesogramma marginata (Robertson 1928). the sexual system was defned and also elaborately The most widely spread, weedy species of Mollugo explained its functonality to achieve self-induced vertcillata, M. nudicaulis and M. cerviana are self- and autogamy, spontaneous autogamy, geitonogamy and insect-pollinated (Pax & Hofmann 1934; Bogle 1970). xenogamy. The positons of stamens and stgmas during In Taiwan, M. pentaphylla is a minor pollen source and afer anthesis were observed to evaluate as to how for Apis mellifera (Lin et al. 1993). In southern India, they facilitate spontaneous autogamy during anthesis honey bees use Mollugo species as pollen source and and fower closure. Further, observatons were also reciprocate the plants with pollinaton (Ponnuchamy et made to evaluate as to how these positons preclude al. 2014). The present study examines how M. cerviana, self-pollinaton when fowers stay open. M. nudicaulis and M. pentaphylla are able to reproduce Insects foraging at the fowers were observed in semi-dry and dry habitats where pollinators are from morning to evening on four diferent days for usually scarce. The principal objectve of this study is their mode of approach, landing, probing behavior to understand how foral biology, sexual and breeding and