Sterility of the coffee berry borer, Hypothenemus hampei (Coleoptera: Curculionidae), caused by the nematode Metaparasitylenchus hypothenemi (Tylenchidae: Allantonematidae)

ABSTRACT

Metaparasitylenchus hypothenemi is an endoparasitic nematode that causes partial or total sterility of coffee berry borer (Hypothenemus hampei) females, although the causes are unknown. Fecundity and the average size of the common and lateral oviduct, vitellarium, and germarium in the four ovarioles (I, II, III and IV) were compared between parasitised and non-parasitised insects to determine the causes of sterility. The nematode significantly lowers the number of oocytes and 86% of parasitised insects (24 out of 28 insects) were sterile, while fecundity in the remaining 13% was non-significantly different to that in non-parasitised insects. No significant differences were recorded in the size of the common oviduct, lateral oviduct, vitellarium, and germarium between parasitised and non-parasitised insects and the nematode does not cause any apparent damage on the surface of the ovary.

KEYWORDS:

• Endoparasite
• potential fecundity
• realised fecundity
• egg fertility
• oocytes

Acknowledgments

We thank Marina Simota Ruíz for technical assistance, Javier Valle Mora for valuable statistical support, and Roxana Bautista Arredondo for assistance with scanning electron microscopy. Comments by two anonymous reviewers are greatly appreciated.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Fernando E. Vega http://orcid.org/0000-0001-8103-5640