Invertebrate herbivory on floating-leaf macrophytes at the northeast of Argentina: should the damage be taken into account in estimations of plant biomass?

Abstract

We assessed the damage produced by invertebrate herbivores per leaf lamina and per m2 of populations floating-leaf macrophytes of Neotropical wetlands in the growth and decay periods, and assessed if the damage produced by the herbivores should be taken into account in the estimations of plant biomass of these macrophytes or not. The biomass removed per lamina and per m2 was higher during the growth period than in decay period in Nymphoides indica and Hydrocleys nymphoides, while Nymphaea prolifera had low values of herbivory in growth period. During decay period this plant is only present as vegetative propagules. According to the values of biomass removed per m2 of N. indica, underestimation up to 17.69% should be produced in cases that herbivory do not should be taking account to evaluate these plant parameters on this macrophyte. Therefore, for the study of biomass and productivity in the study area, we suggest the use of corrected lamina biomass after estimating the biomass removed by herbivores on N. indica. The values of damage in N. indica emphasize the importance of this macrophyte as a food resource for invertebrate herbivores in the trophic networks of the Neotropical wetlands.

The mitochondrial genome of the semi-slug Omalonyx unguis (Gastropoda: Succineidae) and the phylogenetic relationships within Stylommatophora

“…Omalonyx d’Orbigny, 1838 is a genus of succinids endemic to Central and South America and the Caribbean islands characterized by a significant reduction of the shell [ 19 ]. This group of semi-slugs is frequently found in backwater areas, on riparian vegetation, with some species considered to be a pest of some crops (e.g., Nymphoides indica , Pennisetum purpureum ) [ 19 , 21 – 23 ]. They are also natural and potential intermediate hosts for parasites of the genus Leucochloridium Carus, 1835 (Trematoda) and Angiostrongylus Kamensky, 1905 (Nematoda), respectively [ 24 – 27 ].…”

First record of the semi-slug Omalonyx unguis (d’Orbigny, 1837) (Gastropoda, Succineidae) in the Misiones Province, Argentina

“…Omalonyx are herbivorous and have been reported as pests of several plant species such as Nymphoides indica (L.) Kuntze, Hydrocleys nymphoides Willd. Buchenau and Nymphaea prolifera Wiersema without further indication of the species implicated (Martínez and Franceschini 2018). In addition, O. pattersonae Tillier, 1981 and Omalonyx sp.…”

Initial decomposition of floating leaf blades of waterlilies: causes, damage types and impacts

“…Floating leaf blades of waterlilies develop under water and subsequently unroll at the water surface where they are attacked by various organisms, although young leaves can already be attacked under water before they unroll (Lammens & Van der Velde, 1978; Van der Velde et al., 1982; Van der Velde & Van der Heijden, 1985; Martínez & Franceschini, 2018). Responses of waterlilies to attacks include replacing old leaves by new ones, shifting from floating leaves to underwater leaves (Kouki, 1993), producing hydrophobic epicuticular wax layers (Riederer & Müller, 2006; Aragón, Reina-Pinto & Serrano, 2017; Fig.…”

“…Responses of waterlilies to attacks include replacing old leaves by new ones, shifting from floating leaves to underwater leaves (Kouki, 1993), producing hydrophobic epicuticular wax layers (Riederer & Müller, 2006; Aragón, Reina-Pinto & Serrano, 2017; Fig. 1), spines (Zhang & Yao, 2018), sclereids containing calcium oxalate crystals (Brock & Van der Velde, 1983; Franceschi & Nakata, 2005), tough tissue (Kok et al., 1992; Mueller & Dearing, 1994), and plant secondary metabolites such as alkaloids (Hutchinson, 1975) and phenolics (Kok et al., 1992; Vergeer & Van der Velde, 1997; Smolders et al, 2000; Martínez & Franceschini, 2018). This means that only specific species are able to attack the fresh plant tissue.…”