Developmental morphology of stem galls of Diplolepis nodulosa (Hymenoptera: Cynipidae) and those modified by the inquiline Periclistus pirata (Hymenoptera: Cynipidae) on Rosa blanda (Rosaceae)

Abstract

Diplolepis nodulosa (Beutenmüller) induces small, single-chambered, prosoplasmic galls in stems of Rosa blanda Ait. Gall initiation begins when adult females deposit a single egg into the procambium of R. blanda buds. Pith cells at the distal pole of the egg lyse forming a chamber into which the hatching larva enters. Cells lining the chamber differentiate into nutritive cells, which serve as the larval food. Gall growth is characterized by the proliferation of parenchymatous nutritive cells causing gall enlargement. A separate gall vasculature does not form, but instead, gall tissues are irrigated by the existing stem vasculature. Maturation begins when gall tissues cease proliferating and differentiate into distinct layers concentrically arranged around the larval chamber. The innermost layer is composed of cytoplasmically dense nutritive tissue, followed by parenchymatous nutritive tissue, sclerenchyma, cortex, and epidermis. Parenchymatous nutritive tissue differentiates into nutritive tissue and is consumed by the larva. Galls of D. nodulosa are susceptible to anatomical modification by the phytophagous inquiline Periclistus pirata (Osten Sacken). Galls attacked by P. pirata become enlarged and multichambered, with little resemblance to inducer-inhabited galls. Periclistus pirata kill the larva of D. nodulosa at oviposition and deposit several eggs per host gall. Inquiline-occupied galls may contain the eggs of several females. Nutritive tissue induced by D. nodulosa disintegrates. Growth of attacked galls occurs prior to hatching of P. pirata eggs. At egg hatch, the gall appears as an enlarged hollow sphere and larvae disperse over the chamber surface and feed on parenchymatous tissue. Feeding induces tissue proliferation, which surrounds each larva within its own chamber. As galls mature, cells surrounding each larval chamber lignify forming a sclerenchyma sheath. Cells inside the sclerenchyma sheath differentiate into nutritive cells and are consumed by the inquiline larvae.Key words: Rosa, Cynipidae, gall, developmental morphology, inquiline.

Phylogeny and DNA barcoding of inquiline oak gallwasps (Hymenoptera: Cynipidae) of the Western Palaearctic

“…170 species that inhabit plant galls induced by other insects -primarily other gallwasps (Cynipidae; reviewed in Csóka et al 2005). The inquilines are highly specialised herbivores, able to modify the host plant tissues on which they feed, but dependent on true gall inducers to initiate gall formation (agastoparasites sensu Ronquist 1994; Brooks & Shorthouse, 1998;Sanver & Hawkins, 2000;Stone et al, 2002b). They7 attack the galls of hosts in the gallwasp tribes Cynipini (oak gallwasps, hosts to the inquiline genera Ceroptres, Saphonecrus, Synergus, Synophrus and Ufo), Diplolepidini (rose gallwasps, hosts to the inquiline genus Periclistus) and Aylacini (herb gallwasps, hosts to the inquiline genus Synophromorpha) (Ronquist, 1994(Ronquist, , 1999Csóka et al, 2005).…”

Galls induced by cynipid wasps of the genus Diplolepis (Hymenoptera: Cynipidae) on the roses of Canada's grasslands

“…Once the larvae start feeding, they are quickly surrounded by gall cells (Leggo and Shorthouse 2006;Sliva and Shorthouse 2006). As is the case with all cynipids, galls of Diplolepis undergo three phases of development known as initiation, growth, and maturation (Rohfritsch 1992;Brooks and Shorthouse 1998;Sliva and Shorthouse 2006).…”

“…Numerous species of parasitoids have discovered the defenceless larvae of inducers within galls and have become major mortality factors (Brooks and Shorthouse 1998;Csóka et al 2005). In addition to parasitoids, most species of Diplolepis are also attacked by inquiline cynipids of the genus Periclistus that kill the inducers and then alter the anatomy of inhabited galls (Shorthouse 1998).…”

Plant development reprogramming by cynipid gall wasp: proteomic analysis

“…The insect controls the place of gall emergency (Giertych et al 2013). The host usually reacts with necrosis of cells under the egg; the cells below divide and finally enclose the egg (Rey 1992;Brooks and Shorthouse 1998;Pilichowski and Giertych 2017). The gall chamber is formed through cell differentiation and is lined inside with inner-gall tissue, and the outer gall is built with cortical parenchyma.…”

“…The cell layers of the inner-gall tissue decrease during development because the larvae feed on them. The parenchyma cells are changed into nutritive cells as the larvae feed, and they produce lipids and proteins as well as amylases, which are involved in starch decomposition (Bronner 1992;Rey 1992;Brooks and Shorthouse 1998). During maturation, cell division stops, the galls lignify, the larvae mature and pupate, and finally, the gall tissue desiccates (Harper et al 2004).…”