The relationship between the Nigerian garden snailLimicolaria auroraand the mossHyophila crenulata

Abstract

A possible relationship between the moss, Hyophila crenulata and the Nigerian garden snail, Limicolaria aurora was investigated. Freshly ground moss paste, unground moss, waterleaf (Talinum triangulare) paste, a mixture of ground moss and cassava starch paste (1 : 1) and cassava starch paste alone were fed to different groups of snails for 10 days. A field experiment in which some snails were restricted to the moss population on a drainage wall for 10 days was also carried out. There was a significant difference in the live weight of the different groups of snails (P,0.05) in the laboratory experiment. The group fed with moss paste had a significantly higher live weight than any of the other groups. The group fed with unground moss and those in the field experiment actually lost weight indicating an inability to feed on and digest the whole moss. The results indicate that the snails use the moss, which is always moist and cool, only as habitat and not as food. Thus the nutrients trapped within the cells of mosses may only enter the nutrient cycle of the ecosystem when the moss dies and decomposes or by mechanical crushing.

Induced defense and its cost in two bryophyte species

“…Nonstructural carbohydrates such as soluble sugar and starch are considered as the stress‐tolerance biological compounds in plants (Hoch et al, 2002; Poorter and Kitajima, 2007; Machado et al, 2013; Maguire and Kobe, 2015), while cellulose, a structural carbohydrate, provides resistance to herbivore grazing (Herms and Mattson, 1992) and is poorly digested by moss‐feeding animals (Oyesiku and Ogunkolade, 2006). To investigate whether carbohydrate allocation in response to herbivory had changed, we compared the content of soluble sugars, starch, and cellulose spectroscopically at an absorbance of 620 nm using the anthrone method (Eklöf et al, 2008).…”

“…Thus, there may be ecological reasons for bryophytes to develop induced defense against herbivores and a mechanistic basis for inducible defense. However, previous studies of bryophyte-herbivore interactions have focused on herbivore feeding choices (Davidson et al, 1990;Glime, 2006;Markham et al, 2006;Oyesiku and Ogunkolade, 2006;McWilliam-Hughes et al, 2009) and provided no information on whether bryophytes can upregulate their physical or chemical defenses in response to herbivore damage. The idea that investment in defense comes at a cost to plants is fundamental to our understanding of ecology, evolution, and biogeography (Feeny, 1976;Bryant et al, 1983;Jones and Hartley, 1999;Strauss et al, 2002;Moles et al, 2013).…”

“…As the oldest living land plants, bryophytes have antiherbivore defenses that have developed independently of those of ferns, gymnosperms, and angiosperms for over 400 million years (Labandeira et al, 2014). However, most of the existing knowledge about herbivory is based on vascular plants (Gerson, 1982; Davidson et al, 1990; Markham et al, 2006; Oyesiku and Ogunkolade, 2006). Understanding of the types of defense and the mechanism(s) shaping investment in defense in bryophytes lags far behind what is known for vascular plants (Glime, 2006).…”

“…Markham et al (2006) found that protein extracts of six bryophyte species caused a sharp increase in mortality in the fall armyworm ( Spodoptera frugiperda ) and cotton bollworm ( Helicoverpa zea ). Finally, Oyesiku and Ogunkolade (2006) found that cell walls of the bryophyte Hyophila crenulata trap nutrients and reduce palatability to slugs. Bryophytes apparently can effectively deter herbivores, but the forces shaping selection for defense in bryophytes receive little attention.…”

Detecting herbivory in two mosses from an Atlantic Forest, Brazil

“…Snails and slugs have been found eating immature capsules and protonemata of mosses (Davidson et al, 1990;Glime, 2006Glime, , 2010, but records of these animals grazing on gametophytes are rare (Ochi, 1960;Davidson et al, 1990;Merrifield, 2000), and in general, snails and slugs avoid mosses (Oyesiku & Ogunkolade, 2006;Frahm, 2004). Larvae from the family Micropterigidae are sometimes recorded grazing on bryophytes (Powell, 1980;Tuskes & Smith, 1984), and this may be an ancestral interaction between bryophytes and these micropterigids, considered more ancestral lepidopterans (Scoble, 1995).…”