And Host Plants of the Jean Lorougnon Guede Site (Daloa, Côte D'ivoire)
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Journal of Global Biosciences Peer Reviewed, Refereed, Open-Access Journal ISSN 2320-1355 Volume 9, Number 9, 2020, pp. 7937-7953 Website: www.mutagens.co.in URL: www.mutagens.co.in/jgb/vol.09/09/090905.pdf Research Paper DIVERSITY OF LORANTHACEAE (GUIS) AND HOST PLANTS OF THE JEAN LOROUGNON GUEDE SITE (DALOA, CÔTE D'IVOIRE) AMON Anoh Denis-Esdras, KOULIBALY Annick Victoire and MRANKPA Agnero Stephane UFR Agroforesterie, Université Jean Lorougnon Guedé, BP 150 Daloa, Côte d’Ivoire. Abstract Plant formations are an important natural source of products of interest to populations. However, these formations are subject to constant anthropogenic disturbances and parasitic pressures due to attacks in particular of the hemiparasitic vascular plants of the Loranthaceae family which weaken their ecological equilibrium. The present study was carried out in order to inventory the different species of Loranthaceae and their woody host plants on the site of the Jean Lorougnon Guédé University. Itinerant surveys and direct observation methods were used for data collection. In total, 4 species of Loranthaceae have been inventoried. These are: Globimetula braunii (Engl.) Van Tiegh., Phragmanthera capitata (Spreng.) Ballé, Tapinanthus bangwensis (Engl. and K. Krause) Danser and T. globiferus (A. Rich.). The taxonomic diversity of hosts is 43 distributed in 36 genera and 20 families. The families richest in parasitized taxa are Fabaceae (18.60%), Apocynaceae, Mavalceae and Rutaceae, each with 9.30% of host taxa. Among the parasitic species, T. bangwensis and P. capitata are the parasites with broad host spectra. The pairs of infestation values (rate and intensity) of the host plants increase numerically according to their Diameter Breast Height (DBH). The average infestation rate for all host plants is 46.92% and the intensity of infestation is 7.52 tufts/plant. Key words: Loranthaceae; host plants; rate and intensity; Jean Lorougnon Guédé University; Côte d'Ivoire; West Africa. INTRODUCTION Tropical regions are the most diverse biological areas in the world (Myers et al., 2000). In West Africa and Côte d'Ivoire in particular, plant formations are an important natural source of products of interest to people (IPGRI, 1999). Indeed, they provide fertile land for cultivation, firewood, timber and products with food, commercial, medicinal and Author(s) agree that this article remains permanently open access under the terms of the Creative Commons Attribution License 4.0 International License Journal of Global Biosciences Vol. 9(9), 2020 pp. 7937-7953 ISSN 2320-1355 cultural value (Piba et al., 2011). However, these formations subjected to considerable anthropogenic disturbances which weaken their ecological balance (Koulibaly et al., 2016). In addition, parasite pressures due to attacks by vascular plants, chlorophyll hemiparasites of the Loranthaceae family which parasitize many spontaneous woody species and other cultivated plants (Amon, 2006). These hemiparasitic plants in the form of small shrubs live and thrive in abundance on many spontaneous woody species and other cultivated plants which they parasitize with variable intensities, within the same population of woody species (Traoré et al., 2003; Amon, 2014). According to Boussim (2002), these hemiparasitic plants, once implanted on the branches of their hosts, negatively affect the growth, lifespan and production of parasitized subjects. They divert to the harm of the host, using a sucker, water and mineral salts for its development (Salle, 2004). However, according to Soro et al. (2009), any effective struggling to be waged against these plant parasites, a prerequisite to knowing the manifestation of their infestation on their different hosts. In addition, few studies have been carried out on Loranthaceae and host plants in the Central-West of Côte d'Ivoire (Mrankpa, 2019). It therefore appeared appropriate to conduct this study on the site of the Jean Lorougnon Guédé University, where several plantations are infested with Loranthaceae. This study is a contribution to a better knowledge of Loranthaceae and woody host plants. Specifically, it will involve: (1) identifying the species of Loranthaceae, (2) inventorying the woody plants hosting the parasites and (3) evaluating the state of infestation (rate and intensity) of the woody plants. MATERIAL AND METHODS Study area The study was carried out in the Department of Daloa with geographical coordinates 6°27′00'' north Latitude and 5°56'00'' west Longitude, precisely on the site of the Jean Lorougnon Guédé University (Fig. 1), in the Central-West of Côte d'Ivoire, located 408 km from Abidjan. The climate is equatorial with 2 rainy seasons which alternate with two dry seasons. Average annual rainfall over the past 30 years has been 1 550 mm. The vegetation belongs to the mesophilic sector of the Guinean domain (Guillaumet and Adjanohoun, 1971), consisting of forest mosaics and Guinean savannas. www.mutagens.co.in 7938 Journal of Global Biosciences Vol. 9(9), 2020 pp. 7937-7953 ISSN 2320-1355 Fig. 1 : Location of study site in Daloa MATERIALS The biological material composed of Loranthaceae and woody plants on the site. The technical equipment consists of a geographic positioning device (GPS), a digital camera, a pair of binoculars, a tape measure, survey plugs, pruning shears and twine. METHODS The inventory of Loranthaceae species and woody plants was done using the itinerant urvey method associated with that of direct observations after a field visit. The itinerant surveys were carried out for more exhaustive data. It consisted of covering the plantations in all directions, through tracks, development trails, layouts for monitoring anthropogenic activities and other routes created according to the circumstances to identify the plants parasitized, those not parasitized and to collect the measurements Diameter Breast Height (DBH) at 1.30 m from these woody plants. Also, by direct observations, the count of tufts of parasites on the host species. For the enumerating of tufts, it consisted in counting all the tufts of the species or parasite species. The www.mutagens.co.in 7939 Journal of Global Biosciences Vol. 9(9), 2020 pp. 7937-7953 ISSN 2320-1355 identification of Loranthaceae species was made by comparison with the samples of Loranthaceae kept at the Herbarium of the National Floristic Center (CNF) in Abidjan and those listed by certain authors (Traoré et al., 2003; Soro, 2010; Amon, 2014). For the determination of the host plants of Loranthaceae, it was made using of Aké-Assi (2002), Biodiversity of West Africa Forest (Bongers et al., 2005) and by comparing the Flora of the 'Herbarium of the National Floristic Center (CNF) and the Jean Lorougnon Guédé University. The data collected made it possible to calculate: - Infestation rate (Txi): with Txi - Infestation rate; Nip - Number of individuals infected; Nti - Total number of individuals identified; - Intensity of infestation (Ii) : with Ii - Intensity of infestation; Nt - Total number of tufts of Loranthaceae; Ntii - Total number of infested individuals identified; - Parasite specificity rate (Psr) according to Hoffmann (1994): Parasite specificity is high if a substantial number of hosts are parasitized and weak if a small number of species are parasitized. The parasites have been classified as follows: very strong parasitic specificity: [0 to 5 %], average parasitic specificity: ] 5 to 10%] and weak parasitic specificity: > 10%; - Parasitic sensitivity of fruit species It was assessed by the number of parasites per host subject: not very sensitive (1 to 2 parasites), sensitive (3 to 4 parasites) and highly sensitive (5 to 6 parasites). The results of the calculations were analyzed by variance using SPSS 11.0 software. The Tukey test at the 5% threshold was carried out to distinguish the statistical groups at the 5% threshold. www.mutagens.co.in 7940 Journal of Global Biosciences Vol. 9(9), 2020 pp. 7937-7953 ISSN 2320-1355 RESULTS Diversity of Loranthaceae A total, 4 Loranthaceae species have been iventoried and identified on the Jean Lorougnon Guédé University site. These are: Globimetula braunii (Engl.) Van Tiegh. (Fig. 2a), Phragmanthera capitata (Spreng.) Ballé (Fig. 2b), Tapinanthus bangwensis (Engl. and K. Krause) Danser (Fig. 2c) and T. globiferus (A. Rich.) Fig. (2d). They are divided into 3 genera namely Globimetula, Phragmanthera and Tapinanthus. The Tapinanthus genus contains 2 species, either 50% of the parasites inventoried. It is the most important genre. The other two genera are monospecific with each a species (25% parasites). Fig. 2: Loranthaceae species: leafy twigs and inflorescences of G. braunii (a), Inflorescences of P. capitata (b), Inflorescences of T. bangwensis (c) and leafy twig of T. globiferus (d) Diversity of host woody plants Forty-three (43) woody host species of Loranthaceae are listed on the Jean Lorougnon Guédé University site (Table 1). They are divided into 36 genera and 20 botanical families. The family richest in parasitized species is Fabaceae with 8 species, or 18.60% (Fig. 3). Next come the Apocynaceae, Malvaceae and Rutaceae, each with 4 species (9.30%). They are followed by Anacardiaceae, Annonaceae, Bignoniaceae, Lamiaceae, Meliaceae, Moraceae and Rubiaceae with each 2 species (4.65%). Albizia and Citrus with 4 species each (11.11%) are the most diverse genera. They are followed by the genus Annona with 2 taxa (5.56%). The thirty-three (33) other genera each have a taxon (2.78%). These include Alstonia, Bombax, Ceiba, Cola, Ficus, Gmelina,