Yeasts Associated with the Olive Fruit Fly Bactrocera oleae (Rossi) (Diptera: Tephritidae) Lead to New Attractants

Abstract

The olive fruit fly (Bactrocera oleae Rossi) is the primary insect pest in all olive-growing regions worldwide. New integrated pest management (IPM) techniques are needed for B. oleae to mitigate reliance on pesticides used for its control which can result in negative environmental impacts. More effective lures for monitoring olive flies would help to know when and where direct chemical applications are required. The aim of this research was to find new, more effective methods for B. oleae detection and monitoring. Twelve insect-associated yeasts were selected and tested as living cultures in McPhail traps for the attraction of olive flies. Certain yeasts were more attractive than others to B. oleae; specifically, Kuraishia capsulata, Lachancea thermotolerans, Peterozyma xylosa, Scheffersomyces ergatensis, and Nakazawae ernobii, than the industry-standard dried torula yeast (Cyberlindnera jadinii; syn. Candida utilis). The attractiveness of dry, inactive (i.e., non-living) formulations of these five yeasts was also tested in the field. Inactive formulations of K. capsulata, P. xylosa, N. ernobii, and L. thermotolerans were significantly more attractive to B. oleae than commercially available torula yeast. Green lacewing, Chrysoperla comanche (Stephens) (Neuroptera: Chrysopidae), adults were incidentally caught in traps baited with the live yeast cultures. This is the first field study that compares olive fly attraction to yeast species other than torula yeast. Commercialization of yeasts that are more attractive than the torula standard would improve monitoring and associated control of the olive fruit fly.

A Lifetime of a Dispenser-Release Rates of Olive Fruit Fly-Associated Yeast Volatile Compounds and Their Influence on Olive Fruit Fly (Bactrocera oleae Rossi) Attraction

“…Vitanović et al [ 15 , 16 ] and Bego and Burul et al [ 17 ] also demonstrated in their previous studies that some OFF-associated yeast volatile compounds attract OFFs. Therefore, it was necessary to test the individual volatile compounds under controlled conditions and in the field, as well as to test the performance of the diverse types of dispensers to improve our knowledge of the chemical properties of the volatile compounds.…”

“…Semiochemicals represent a wide range of volatile and nonvolatile organic substances or mixtures that depend on various physicochemical properties, such as the nature of the semiochemical itself, its volatility and solubility, and the lifetime of the semiochemical in the environment, highlighting the influence of temperature, which can allow increased diffusion of semiochemicals, as one of the most important abiotic factors [ 6 ]. In the context of monitoring and control of OFF, several studies have shown that OFF is indeed attracted to selected semiochemicals such, as plant volatiles [ 8 , 9 , 10 , 11 , 12 , 13 , 14 ] and yeast volatiles [ 15 , 16 , 17 ], the emission of which serves as a volatile signal for insect foraging [ 18 ]. Vitanović et al [ 16 ] reported the attraction of various yeast species isolated from different habitat sources, such as infested olive fruit, the surface of OFFs, the guts of larvae and adult insects, and other insect species to OFF.…”

“…In the context of monitoring and control of OFF, several studies have shown that OFF is indeed attracted to selected semiochemicals such, as plant volatiles [ 8 , 9 , 10 , 11 , 12 , 13 , 14 ] and yeast volatiles [ 15 , 16 , 17 ], the emission of which serves as a volatile signal for insect foraging [ 18 ]. Vitanović et al [ 16 ] reported the attraction of various yeast species isolated from different habitat sources, such as infested olive fruit, the surface of OFFs, the guts of larvae and adult insects, and other insect species to OFF. Upon further examination of these yeast species, Vitanović et al [ 15 ] noted the presence of several volatile compounds, including isoamyl alcohol, 2-phenethyl acetate, isobutanol, isobutyl acetate, 2-phenethyl acetate, and 2-octanone.…”

Production of high protein yeast using enzymatically liquefied almond hulls

“…As demonstrated in our previous screening studies, a yeast screening schema is often guided and modified based on discoveries made during the study [41][42][43][44]. Two key results that guided the screening strategy in this study were that the AHH contained significant quantities of galacturonic acid, and that few yeasts in the initial screening sets could consume this compound.…”

Yeast–insect interactions in southern Africa: Tapping the diversity of yeasts for modern bioprocessing

“…In addition, the complexity of VOCs from insect derived yeasts has been tapped into for flavorants, perfumes, biosurfactants and antimicrobial products (Czajka et al, 2018; Gupta et al, 2015; Rau et al, 2005). VOCs from insect‐associated strains are used in insect pest luring traps and repellents (Ljunggren et al, 2019; Vitanović, 2020). Although agriculture is as ancient as humanity, biological control of insect pests and other microbial pathogens as a concept could be classified as modern.…”