session 7: probiotic diets to increase queensland fruit fly male performance as part of the sterile...

biosecurity built on science

Understanding the microbiome of Queensland fruit fly to improve sterile insect technique

1. Plant Biosecurity Cooperative Research Centre (PBCRC), Australia

2. Elizabeth Macarthur Agricultural Institute (EMAI), NSW Department of Primary Industries

3. Hawkesbury Institute for the Environment (HIE), Western Sydney University

Plant Biosecurity Cooperative Research Centre

D Woruba1,2,3, O Reynolds2, M Riegler3, J Morrow3 & T Chapman1,2


Queensland fruit fly (Qfly), Bactrocera tryoni Australia’s most significant

horticultural insect pest threatening crops valued at $640 million

Damages fruits and vegetables and affects trade

Broad-spectrum chemicals are being phased out

Current management includes monitoring, targeted chemical application, cultural practices and Sterile Insect technique (SIT)


Sterile Insect Technique

SIT is “a method of pest control using area-wide inundative releases of sterile insects to reduce reproduction in a field population of the same species” FAO, 2014 (Insect birth control)

The success of SIT depends on sterile males mating with wild females

Mass rearing and irradiation lead to reduced fitness and performance of sterile males


Probiotics

Greek “pro” + “bios” = "for life.”

“Live microorganisms which when administered in adequate amounts confer a health benefit on the host” FAO & WHO, 2006.


Probiotics

Human products

Metchnikoff 1907

Animal products

Beneficial bacteria


Beneficial bacteria in Insects

Beneficial bacteria in insects have been well documented- E.g. Obligate endosymbiosis of aphids and the Buchnera

bacteria- E.g. Gut bacteria linked to evolution of herbivory in ants

Tephritid fruit flies gut bacteria studied since early 1900s


Aim

Characterization of complete gut microbiome of Qfly- Reared (lab) and wild Qfly populations- Ecological distribution (location & host)

Formulation of probiotic supplements to improve Qfly SIT


Literature Review

Woruba et al (review manuscript) submitted

Roles of bacteria in tephritids:

- Protein metabolism

- Carbohydrate metabolism

- Longevity

- Attraction and communication

- Mating and reproductive performance


-80°C StorageGut isolation

Fitness testsProbiotic

formulations Culture bacteria

Field Collection Molecular ID

The “sexy back” plan

Effective “sexy” sterile male Qfly


Reared Qfly Microbiome Pupae;

- EMAI (lucerne as diet bulking agent) Sterile Fertile

- HIE (carrot as diet bulking agent) Fertile

Adults- Tenerals (≈12 hrs post-eclosion) - Mature (14 days post-eclosion).

yeast and sugar (3:1) sugar only

Adult rearing


♂ ♀ ♂ ♀ ♂ ♀ YS♂ YS♀ S♂ S♀ S♂ S♀ YS♂ YS♀ YS♂ YS♀ S♂ S♀0

5000

10000

15000

20000

25000

30000

35000

40000

45000 Average count of 16s rDNA reads

Reared Qfly Microbiome: Results

TENERALS

MATURE

EMAI EMAIHIE HIE

Sterile Fertile

CO

UN

TS


♂ ♀ ♂ ♀ ♂ ♀

YS♂

YS♀ S♂ S♀ S♂ S♀ YS♂

YS♀

YS♂

YS♀ S♂ S♀

Fertile

Fertile

Ster-ile

Ster-ile

Fertile

Fertile

Fertile

Fertile

Fertile

Fertile

Ster-ile

Ster-ile

Ster-ile

Ster-ile

Fertile

Fertile

Fertile

Fertile

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

EnterobacteriaceaeAcetobacteraceaeLactobacillaceaeXanthomonadaceaeFlavobacteriaceaeLegionellaceaeMoraxellaceaeSphingomonadaceaeHyphomicrobiaceaePseudomonadaceaeOthers

EMAI EMAI

MATURE

HIE

Reared Qfly Microbiome: ResultsTENERALS

Bacterial diversity of mass-reared teneral and mature Bactrocera tryoni

HIE


Reared Qfly Microbiome: Conclusion

Microbiome of mature Qfly is dominated by Enterobacteriaceae

Teneral flies have low bacterial density

Bacterial population increases with fly maturation (either through cell division or uptake from environment)

Ideal time point of supply of probiotic candidates is in teneral stage


Source: Dominiak & Daniels 2012

MareebaAtherton

Kuranda

RedlandsMt. Coot-tha

Sunshine Coast

Central Coast

HawkesburyCamden

Wild Qfly Microbiome

Qfly Sampling Wild

Native and Commercial Habitats

Host fruits Locations

Lab reared Sterile and fertile


Use of 5 selective media for culturing bacterial isolates

Identification of isolates using molecular and bichemical tools

Candidates identification and culturing

Culture bacteria


Identification of potential probiotic candidates and develop formulations

Test for: Improved stress resistance & survival Enhanced sexual mating performance (Flyagra)

Fitness tests

Fitness testsProbiotic formulations


Thank you

The gutsy search for a sexy solution

session 7: probiotic diets to increase queensland fruit fly male performance as part of the sterile...

Science