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International Journal of Current Advanced Research ISSN: O: 2319-6475, ISSN: P: 2319-6505, Impact Factor: 6.614 Available Online at www.journalijcar.org Volume 8; Issue 04 (F); April 2019; Page No.18462-18468 DOI: http://dx.doi.org/10.24327/ijcar.2019.18468.3530 Research Article AN INTRODUCTORY STUDY ON A FOLIICOLOUS LICHEN FOUND ON COMMON TREES IN KERALA, INDIA: CHARACTERIZATION OF ITS SYMBIOTIC PARTNERS Reshma. R. S* and Joseph Job Department of Botany, St. Berchman’s College, Changanacherry, Kottayam, Kerala - 686 101, India ARTICLE INFO ABSTRACT Article History: Lichens are composite living organisms formed by the symbiotic relationship between the Received 10th January, 2019 photobiont and the mycobiont. Foliicolous or epiphyllous lichens are those that grow on the Received in revised form 2nd leaves of vascular plants. In the present study we investigated the formation and February, 2019 reproduction of a Phyllophiale like foliicolous lichen which inhabited the leaves of almost Accepted 26th February, 2019 all common trees in Kerala, India, especially Mangifera indica, Ixora coccinea, Mesua Published online 28th April, 2019 ferrea, Syzygium cumini and Garcinia mangostana. Morphological examination of the lichen peels revealed Phycopeltis as the major photobiont. Trebouxia cells were also found Key words: to be associating with the lichen. The study showed the presence of a fungal associate in all the collected lichen samples. We could culture the fungus in vitro. DNA barcoding using Lichen, Phycobiont, Mycobiont, Phycopeltis, primers of ITS showed that fungal associate may be a member of Botryosphaeriaceae. In Phyllophiale, Trebouxia vitro culture of lichen seemed to produce many structures which were not observed during their natural development. The study also attempted to investigate the effect of the foliicolous lichen on the rate of photosynthesis of the host plant and found that that the presence of the lichen on the leaf surface has no retarding effect on the rate of photosynthesis. Copyright©2019 Reshma. R. S and Joseph Job. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. INTRODUCTION Several members of the Trentepohliales, including the genera Cephaleuros, Trentepohlia, Phycopeltis, Physolinum and Lichen is a beautiful example of mutualistic symbiosis Printzina are other common phycobionts in lichens. The most between fungi and algae or cyanobacteria. The fungal and commonly occurring genus of symbiotic cyanobacteria were algal partners were called mycobiont and photobiont Nostoc and Scytonema. Almost all these phycobionts were respectively. The algal and/or cyanobacterial partners were capable of free living in the absence of a suitable fungal photosynthetic. They provided carbohydrates and vitamins to partner. About 99 % of lichen mycobionts reported were the fungus. Cyanobacteria could fix atmospheric nitrogen. The ascomycetes, whereas basidiomycetes comprised only less fungus, in turn, protects its partners from desiccation and than 1 % (Brodo, 2001). shades them from strong sunlight. Foliicolous or epiphyllous lichens were those that grew on the Development of new thallus takes place only when the leaves of vascular plants. Such lichens were widespread and environment is favorable. Even under such conditions, lichen were especially common in the tropical areas where the thallus could develop only if both symbionts were present in atmospheric humidity was high. Many lichenologists have the neighborhood. Lichens commonly reproduced when attempted to culture whole lichens and the separate or fragments of both algal and fungal tissues dispersed and grew recombined symbionts (Ahmadjian, 1967, 1973; Galun, 1988). to form a new lichen thallus (Brodo, 2001). In many lichens In most cases, lichen tissue culture and cultures derived by vegetative propagules such as soredia, isidia and thallus recombining symbionts that have been cultured separately fragments were the major means of reproduction. Often the remained as undifferentiated cell aggregates, but such mycobiont was dispersed by means of ascospore, basidiospore, aggregates are very useful for many biological experiments conidia or gemmae. The new mycelium developing from such (Ahmadjian, 1973). The impact of foliicolous lichens on the propagules has to come across a suitable free living rate of photosynthesis of the host plant was a point of debate. alga/cyanobacterium to initiate lichenization. Although several lichen identification keys were available, About 90% of all known lichens had a green alga as a there were several unidentified foliicolous lichens. In the symbiont. Among these, Trebouxia was reported to be the present study we made an attempt to investigate in detail most common genus, occurring in majority of lichens. widespread foliicolous lichen found distributed on all most all *Corresponding author: Reshma. R. S the common trees in Kerala, India and to characterize its Department of Botany, St. Berchman’s College, Changanacherry, symbiotic partners. Kottayam, Kerala - 686 101, India International Journal of Current Advanced Research Vol 8, Issue 04(F), pp 18462-18468, April 2019 MATERIALS AND METHODS Biosystems) using the Big Dye Terminator v3.1 Cycle sequencing Kit (Applied Biosystems, USA) following Plant Material manufactures protocol. The cleaned up air dried product was Leaves from different plants, Mesua ferrea, Mangifera indica, sequenced in ABI 3500 DNA Analyzer. The sequence quality Ixora coccinea, Syzygium cumini and Garcinia mangostana, was checked using Sequence Scanner Software v1 (Applied harboring the particular foliicolous lichen were collected and Biosystems). The sequence similarity was analyzed using the observed (Fig 1). alignment tool BLAST. Photosynthesis studies Photosynthesis was measured by monitoring gas exchange systems using Infrared gas analyzers (IRGAs). In IRGAs, the reduction in IR transmission is a function of the concentration of CO2. A leaf was enclosed in a chamber, sealed to avoid gas exchange with the atmosphere, and the rate at which the CO2 and H2O concentration changes in the chamber were Fig 1 Lichen infected leaves of A. Mesua ferrea, B. Mangifera indica, C. monitored. The sample and reference analyzers can be Ixora coccinea, D. Syzygium cumini and E. Garcinia mangostana matched, without altering conditions in the leaf chamber. Morphological observation RESULTS Microscopic observation Development of lichen in vivo A strip of transparent universal adhesive film was gently applied on the infected surface of the leaf. The adhesive tape Epidermal peels observed under microscope revealed the was then carefully pulled away from the surface, peeling away presence of algal cells, fungal hyphae and lichens at different the epiphyllous lichen from the epidermis. Adhesive tape with developmental stages. Two different types of algal cells were attached lichen was immediately transferred to a glass slide found to be associated with the lichen, discoid filamentous and observed under a microscope. The images were captured green alga Phycopeltis and unicellular green alga Trebouxia using Olympus CH-20i Microscope camera. (Fig 2A and B). Phycopeltis was found distributed abundantly in the free-living state (Fig 2C). Phyllophiale like lichen Alkaline treatment thallus, comprised of the phycobiont Phycopeltis, with a The developmental stages were determined by examining multicellular thallus of closely packed, tightly branched radial various discrete stages found in the field material. Leaf slices filaments forming a disc like structure covered by a network of containing lichens were soaked overnight in NaOH (0.6M). fungal hyphae were observed (Fig 2D). In some areas the Equal volume of HCl was used to neutralize the NaOH hyphae surrounding coccoidal green algal cells forming solution. From the treated leaves the lichen could be easily distinctive structures could be seen (Fig 2E). The hyphae grew stripped. The separated lichen thallus was repeatedly rinsed towards, between and around the filamentous branches of with sterile water. The morphological traits were observed Phycopeltis algal cells producing lichenized hyphal branches under microscope, with or without staining using lactophenol which form the mat like fungal network (Fig 2F). It was not cotton blue. The images were captured using Olympus CH-20i possible to find out the origin of association of lichenized Microscope camera. fungal hyphae and the algal partner. In vitro culture Sterilized Water agar medium and Bolds Basal media were used to culture the mycobiont and the lichen / photobiont respectively. Lichen thalli from the leaves were scraped using a sterile surgical blade and dissecting needle and inoculated onto the sterilized media. All the cultures were incubated under ambient conditions. The growth of culture aggregates was observed on every alternative day using a light microscope. DNA barcoding using universal primers of ITS DNA isolation was performed using NucleoSpin® Plant II Kit (Macherey-Nagel). The eluted DNA was stored at 4oC. The quality of the DNA isolated was checked using agarose gel electrophoresis. PCR Analysis was carried out with specific Fig 2A,B. Discoid filamentous green alga Phycopeltis and unicellular green ITSprimers (Forward ITS-1F: algal cells scattered singly or in groups near the ends of fungal hyphae. Fig2C. 5’TCCGTAGGTGAACCTGCGG3’ and Reverse ITS-4R: Phycopeltis