Original paper
The intrinsic diversity of Nezara viridula gut symbionts affects the host fitness decline promoted by primary symbiont elimination
Prieto, Sofia V.; Brunetti, Matteo; Magoga, Giulia; Orrù, Bianca; Gonella, Elena; Montagna, Matteo; Alma, Alberto
Entomologia Generalis Volume 43 Number 6 (2023), p. 1151 - 1160
published: Dec 11, 2023
published online: Nov 21, 2023
manuscript accepted: Oct 9, 2023
final revised version received: Oct 2, 2023
manuscript revision requested: Sep 14, 2023
manuscript received: Jul 31, 2023
DOI: 10.1127/entomologia/2023/2224
Open Access (paper may be downloaded free of charge)
Abstract
Pentatomid insects harbour an obligate gut symbiont, vertically transmitted via egg smearing by the females. The disruption of symbiont acquisition can be exploited for pest management, by spraying the egg surface with anti-symbiont agents, yet the insect response to symbiont deprivation remains a determining aspect of the success of this strategy. Here the effect of anti-symbiont egg masses treatment was assessed in an Italian population of the southern green stink bug Nezara viridula under field and laboratory conditions. In soybean fields, N. viridula was poorly affected by treatment, whereas in laboratory, nymphs deriving from treated egg masses underwent increased mortality and symbiont abundance decline. The primary symbiont dominated the microbiome of non-treated nymphs showing low mortality. Conversely, dysbiosis was recorded in treated samples as well as in control nymphs with high mortality. Nonetheless, dysbiosis induced by treatment was not in all cases associated with high mortality, and symbiont was missing in some non-treated samples as well. Five variants of a Pantoea symbiont were found, with higher variant diversity in untreated samples with low mortality. Altogether, our results provide information about the gut microbiota dynamics in the early nymphal instars of N. viridula and suggest a still incomplete dependence on the symbiont. However, egg masses anti-symbiont treatment increased mortality, therefore symbiont-targeted control may be used against N. viridula as a supplementary tool under high pest pressure.
Keywords
interaction •
dysbiosis •
soybean •
pentatomid •
16SrRNA sequencing •
Pantoea
•
microbiota dynamics