Structural and histochemical profile of Lopesia sp. Rübsaamen 1908 pinnula galls on Mimosa tenuiflora (Willd.) Poir. in a Caatinga environment

Abstract

Structural and histochemical profi le of Lopesia sp. Rübsaamen 1908 pinnula galls on Mimosa tenuifl ora (Willd.) Poir. in a Caatinga environment). Gall-inducing insects can change the anatomical pattern of host plant tissues by inducing peculiar gall morphotypes. In this study, the structural changes observed in Lopesia galls on Mimosa tenuifl ora resemble those found in other Cecidomyiidae, with two tissue compartments. Nevertheless, the parenchyma layers of the inner compartment, between the mechanical zone and the nutritive tissue, are peculiar. Gall development does not impair the synthesis of any compounds detected by histochemical tests on non-galled tissues of M. tenuifl ora. Lignin, polyphenols, alkaloids and terpenoids were detected in the outer compartment, suggesting their involvement in chemical defence of galls. Proteins, reducing sugars and lipids were detected both in outer and inner compartments, whereas nutritive tissue is rich in reducing sugar. This profi le is linked with the nutrition of the gall-inducing insect. The Caatinga environment does not seem to constrain the development of galls, but the thick periclinal cell wall and homogeneous parenchyma may contribute to the control of humidity and light radiation, thus favouring the survival of the gall-inducing insect. Keywords: Cecidomyiidae, gall anatomy, leaf gall, plant insect interaction RESUMO -(Perfi l estrutural e histoquímico de galhas foliares de Lopesia sp. Rübsaamen 1908 em Mimosa tenuifl ora (Willd.) Poir. em ambiente de Caatinga). Insetos galhadores podem alterar o padrão anatômico dos tecidos das suas plantas hospedeiras, induzindo morfotipos peculiares de galhas. Neste estudo, as modifi cações estruturais observadas nas galhas de Lopesia sp. em Mimosa tenuifl ora assemelham-se àquelas evidenciadas em outras galhas de Cecidomyiidae, com dois compartimentos teciduais. No entanto, as camadas de parênquima no compartimento interno entre a zona mecânica e o tecido nutritivo são peculiares. O desenvolvimento da galha não bloqueia a síntese de quaisquer compostos detectados nos tecidos não galhados de M. tenuifl ora, por meio de testes histoquímicos. Ligninas, polifenóis, alcaloides e terpenoides foram detectados no compartimento externo, sugerindo seu envolvimento na defesa química das galhas. Proteínas, açúcares redutores e lipídios foram detectados tanto no compartimento externo quanto no interno, e o tecido nutritivo é rico em açúcares redutores. Esse perfi l está ligado à nutrição do galhador. O ambiente da Caatinga parece não impor restrições ao desenvolvimento da galha, mas, a parede celular periclinal espessa e o parênquima homogêneo parecem contribuir para o controle da umidade e da radiação, favorecendo à sobrevivência do inseto galhador. Palavras-chave: anatomia de galha, Cecidomyiidae, galha foliar, interação inseto-planta

Are Fabaceae the principal super-hosts of galls in Brazil?

“…The co-evolution of Fabaceae species and gall-inducing insects has given rise to a wide variety of associations that still require indepth biological and ecological examination, for relatively little is currently known about their ontogeny, structure, chemistry (e.g., Isaias 1998, Isaias et al 2006, Oliveira & Isaias 2009, 2010, Sá et al 2009, Suzuki et al 2015, Nogueira et al 2018 or ecology (Almeida et al 2006). The synthesis provided in the current…”

Structural and Nutritional Peculiarities Related to Lifespan Differences on Four Lopesia Induced Bivalve-Shaped Galls on the Single Super-Host Mimosa gemmulata

“…The protein accumulation in the nutritive cells of the Lopesia galls can have antioxidant function due to highest cellular metabolism in this tissue compartment. The accumulation of lipids in the storage, and/or typical nutritive tissue of Cecidomyiidae galls on different host plants are linked to the intrinsic metabolism of the host plants (Moura et al, 2008;Oliveira et al, 2010;Ferreira and Isaias, 2014;Amorim et al, 2017;Nogueira et al, 2018), as is true for M. gemmulata. The lipid droplets accumulated in the common storage tissue are related to the maintenance of the cellular machinery, while in the nutritive cells, they are food resources for the Lopesia galls.…”

The mechanism of plant gall induction by insects: revealing clues, facts, and consequences in a cross-kingdom complex interaction

“…environmental factors (Nogueira, Costa, Silva, & Isaias, 2018), and shelter against natural enemies (Mani, 1992;Ananthakrishnan, 1998;Raman, Schaefer, & Withers, 2005;Tooker, Rohr, Abrahamson, & De Moraes, 2008;Huang et al, 2015;Isaias et al, 2018). The meaning of the adaptive value of galls and the kind of biological interaction existing between gall-inducing insects and their host plants is the subject of a continuous debate among the different groups of researchers that work in the field (Nyman & Julkunen 2000;Stone & Schönrogge, 2003).…”

“…Tissues near the inducing insect show cytological and morphological changes that benefit its feeding process and development. This tissue, also known as "nutritive tissue", commonly presents high concentrations of sugar (Nogueira et al, 2018), lipids, proteins, nitrogen, and other nutrients that provide a continuous source of food for the insect and show intense phosphatase activity (Miles, 1968;Rohfritsch & Shorthouse, 1982;Shorthouse & Rohfritsch, 1992;Raman, 2011, Oliveira & Isaias, 2010Oliveira et al, 2011;Nabity, Haus, Berenbaum, & Delucia, 2013;Huang et al, 2015;Oates et al, 2016;Ferreira et al, 2017;Isaias et al, 2018). Typical nutritive cells show a dense cytoplasm with abundant cell organelles, fragmented vacuoles, a hypertrophied nucleus and nucleolus, and dedifferentiated plastids clustered around the nucleus, as well as chloroplasts modified to varying degrees and modified cell walls (Shorthouse & Rohfritsch, 1992;Raman, 2011;.…”

“…Research conducted on galls of different species of plants have revealed that the composition and concentration of chemical substances in these structures can differ from those of other plant tissues and organs Saltzmann et al, 2008;Giron & Huguet, 2011;Huang et al, 2015;Oates et al, 2015;Hall, Carrol, & Kitching, 2017;Kot, Jakubczyk, Karaś, & Złotek, 2017). Tissues near the outside of the gall frequently accumulate high levels of tannins and other chemical compounds related to the process of defense of the gall and, in consequence, of the insect (Ananthakrishnan, 1998;Li et al, 2017;Chen et al, 2018;Nogueira et al, 2018). A study by Vereecke et al (1997) revealed that the chemical composition of ethanol and aqueous extracts of galls produced in the leaves of Nicotiana tabacum differs drastically from that of non-infected plant tissue extracts.…”