Investigation of the Allelopathic Potential of Nephrolepis cordifolia (L.) C. Presl against Dicotyledonous and Monocotyledonous Plant Species

Invasions by non-native plants are considered a threat that decreases biodiversity and negatively affect the abundance of native plant species (Callaway and Ridenour, 2004). The ability of invasive plant species to grow earlier than neighboring native species, to spread swiftly, to have high potential for resource competition, and to create monocultures in invaded areas, may contribute to their successful colonization and establishment (Bais et al., 2003; Callaway et al., 2005; McGeoch et al., 2010; Guido et al., 2017). The natural phenomenon known as allelopathy has been suggested as a possible mechanism for the success of invasive species over native species (Prati and Bossdorf, 2004) because allelochemicals released from various parts of an invasive plant, transformed and decomposed during decay, can negatively affect the growth and/or development of surrounding native plants either directly or indirectly (Rice, 1984; Callaway and Ridenour, 2004). This ecological mechanism, therefore, has drawn the attention of researchers in the context of the utilization of plantplant interactions for controlling other plants, especially weed species, which could be useful for the improvement and development of sustainable agricultural management. Ferns are one of the most diverse groups of vascular plants in forest habitat. They are also very tolerant to environmental stresses and have the ability to adapt the changing environmental conditions, which helped some fern species to become naturalize and spread themselves into the native forest (Dixit, 2000; Mehltreter et al., 2010; Watkins and Cardelús, 2012; Kamrul-Haque et al., 2016). Several researchers have investigated the possible mechanisms for the successful invasion of some fern species that may associate with allelopathy, and have reported that allelochemicals may influence the competitiveness and invasiveness of those plant species (Wang et al., 2014; Kato-Noguchi, 2015). Nephrolepis cordifolia (L.) C. Presl is an ornamental fern in the family Nephrolepidaceae. The plant is distributed mostly in tropical and subtropical regions throughout the world (Hovenkamp and Miyamoto, 2005). N. cordifolia is also often planted as a ground cover because it adapts well to a wide variety of soil types, tolerates sun and drought, and grows in both epiphyte (on rock) and terrestrial habitats (Cheng et al., 2001; Riefner and Smith, 2015). This fern can spread rapidly by means of rhizomes, stolons, tubers, and spores, and eventually form large colonies. N. cordifolia has been introduced as an invasive species in some areas such as New Zealand, Florida, Australia, and California (Wotherspoon and Wotherspoon,