New Horizons in Insect Science Towards Sustainable Pest Management

347

Reproductive Alterations by

Wolbachia in the Braconid Cotesia

vestalis (Haliday)

K. Srinivasa Murthy, T. Venkatesan, S. K. Jalali and

S. L. Ramya

A. K. Chakravarthy (ed.), New Horizons in Insect Science: Towards Sustainable Pest Management,
DOI 10.1007/978-81-322-2089-3_30, © Springer India 2015

K. S. Murthy () · T. Venkatesan · S. K. Jalali ·
S. L. Ramya
National Bureau of Agriculturally Important Insects,
Bellary Road, Bangalore 560024, Karnataka, India
e-mail: [email protected]

Abstract

The endosymbiotic bacteria Wolbachia, associated with a number of hy-

menopteran parasitoids play role in the metabolism, physiology, and re-

production of their hosts. The impact on female progeny due to Wolbachia

infection in the braconid Cotesia vestalis was investigated in different

geographic populations of the parasitoid. The populations cured of Wo l-

bachia recorded a reduction in male progeny compared to those infected.

The sex ratio skewed toward males in the Wolbachia eliminated popula-

tions, altered toward higher females, when there was infection. There was

36.6 % increase in female progeny over the males. The exploitation of

Wolbachia for the biological manipulations of the parasitoid for effective

pest management is discussed.

Introduction

Symbiotic bacteria have been associated with a
number of parasitoids, known to inflict types of
metabolic, physiological, and reproductive al-
terations, with the sex regulatory bacteria being
the most frequent ones. Among the sex regula-
tors, Wolbachia infects a large number of species
including parasitic hymenoptera. About 2/3rd of

all insect species are infected with Wolbachia

(Werren and Windsor 2000 ). To date Wolbachia

have been detected in 31 genera and 70 species of

parasitic hymenoptera, as well as three dipeteran

parasitoids, 26 % of parasitoid wasps have Wo l-

bachia (Iturbe and O’Neill 2007 ). Wolbachia

spp. is maternally inherited obligate intracellular

bacteria belonging to the α proteobacteria. The

bacteria infect the reproductive tissues (ovaries

and testes) of arthropods and are transmitted

through the egg cytoplasm and alter reproduc-

tion in their hosts. Wolbachia arthropod rela-

tionships have variously been described as mu-

tualistic (Girin and Bouletreau 1995 ), parasitic

Keywords

Cotesia vestalis · Endosymbiont · Fitness benefits · Wolbachia