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Services: insect rearing
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Host and Parasitoid Rearing
Dr. Paul Flinn Technician: Ken Friesen
Abbrev. LGB RGB STGB
Common Name Lesser grain borer Rusty grain beetle Sawtoothed grain beetle
Scientific Name Rhyzopertha dominica Cryptolestes ferrugineus Oryzaephilus surinamenis
Parasite Theocolax elegans Cephalonomia waterstoni Cephalonomia tarsalis
Grain moisture 10-12% 13% 13%
Chamber temp. 30?C 30?C 30?C
Chamber humidity 60% RH 75% RH 75% RH
Unit Quart Quart Pint Pint meth. 1 Pint meth. 2
Wheat full: whole grain 300 ml crimped;
balance whole		 none full: crimped half: crimped
Brewer's yeast none 1/4 tsp 1 Tbsp 1 tsp 1 tsp
Wheat germ none 1/4 tsp 1 tsp none none
Other 1/4 tsp flour none 1/2 pint flour none half rolled oats
Starting # adults 100 400 (0.3 ml) 100 75 50


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Index

Transferring insects
Equipment
Media
Tips and tricks
Lesser grain borer - Quart
T. elegans (host: LGB) - gallon
T. elegans (host: LGB) - pint
Rusty grain beetle - Quart
Rusty grain beetle - flour - pint
C. waterstoni (host: RGB) - gallon
C. waterstoni (host: RGB) - pint
Sawtoothed grain beetle - pint - method 1
Sawtoothed grain beetle - pint - method 2
C. tarsalis (host: STGB) - pint
C. tarsalis (host: STGB) - gallon

Equipment
U.S. Standard sieves
When working seriously with stored grain product insects, certain tools and supplies are necessary. These include sieves and seed pans, which can be purchased from Seedburo Equipment Co., Fisher Scientific, or other analytical supply companies. Most of the tools in the following list are available from the above, or can be improvised.
(Disclaimer: Mention of manufacturer products is for information purposes only and does not imply endorsement by the USDA to the exclusion of others.)

  • Sieves -Various sizes of U.S. Standard sieves are used to clean grain and to separate insects form the grain. Separate sets of sieves are recommended for each type of insect, to avoid cross-contamination.
  • Spouted sample pans - Sample pans are extremely useful for handling insects and grain.
  • Rearing containers- Various sizes of canning jars will serve to rear insects, provided the band contains a 7.0 cm circle of filter paper instead of the cap. Also, gallon jars and five gallon buckets will work, if a fine mesh is fitted into the lid.
  • Rearing chambers - Chambers with reliable temperature and relative humidity controls are very important in most cases.
  • Aspiration - It is useful to have some form of vaccum system (mouth or mechanical) to aid in collecting insects by means of a trap system.
  • Brushes - Different sizes and fiber types help manipulate and handle insect cultures.
  • Microscope - Periodically, a microscope will be necessary to identify or separate insects.

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Media

  • Grain
    • Aquiring wheat - Wheat needs to be of average to good quality, and pesticide free. The best method is is obtaining the wheat directly from the producer.
    • Cleaning - It is desireable to clean the wheat 1-2 times before rearing insects. This can be done with hand sieves for small volumes, or some form of mechanical sieve or dockage tester may be used if needed and available.
    • Moisture - Low moisture wheat may need to be tempered with the appropriate ammount of water to adjust it to optimal rearing properties. High moisture wheat needs to be guarded against molding before use.
    • Storage - Ideally, grain for rearing insects would be frozen and then stored at 15?C or cooler, until a few days before it is needed. This protects against insect and fungal growth.
    • Crimped wheat - This is wheat which has been crushed or deformed to a moderate degree in order to increase the insects' access to the germ.
  • Additives - Flour, oatmeal, wheat germ and brewer's yeast can be purchased at most supermarkets or health food stores. It is convenient if the flour and wheat germ are fine enough to pass through a #40 sieve.

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Tips and Tricks

  • Wasps are quick and good climbers- be alert and quick, but gentle.
  • STGB are good climbers - watch closely.
  • Wasps can be handled well w/ a camel hair brush, small funnel, and tefloned bottle. Static charge can can be defeated by breathing on the affected item.
  • RGB can sort themselves from fine material if poured onto a petri dish lid positioned properly in a pan.
  • Avoid high densities and poor ventilation to avoid carbon dioxide selection.
  • Periodically wash insect-handling equipment with hot water and a distilled water rinse

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LGB - Quart
LGB : lesser grain borer (Rhyzopertha dominica)

  • 600 g whole wheat (or full)
  • 1/4 tsp fine flour (mixed in: stimulates egg-laying)
  • Old jar sifted w/ #14 & #30 sieve (once a week)
  • Contents of #30 sieve (adults) put on new media
  • Grain and fine materials returned to old jar
  • Record oviposition and parental dates
  • Use 100 parental adults
  • Parental adults replaced every 2 months
  • Parental adults should be transferred to new media once a week
  • Generation time is about 30 days
  • Chamber temp. 30?C
  • Chamber humidity 60% RH
  • wheat moisture 10-12%

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T. elegans (host: LGB) - gallon (continuous culture)

  • Add 1/2 Quart of 3 to 4-week-old LGB culture to top of gallon jar
  • When gallon is full (to shoulder), dump top 1/3 into new jar, and add food.
  • Feed weekly

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T. elegans (host: LGB) - pint

  • Add 1-2 inches of 3-4 week-old LGB culture to pint jar
  • Old jar of T. elegans sifted w/ #14, #40, & #70
  • Return grain
  • 12-15 adult wasps added infested grain
  • Record oviposition and parental dates
  • Oviposition time is 10 (9-14) days
  • Seed number is 12-15 wasps
  • When harvesting wasps, use a subset of the new wasps to propagate the culture
  • Sift wasps gently
  • Wasps are quick and clingy - be alert and quick, but gentle
  • Generation time is 14-19 (most 16) days
  • Chamber temp. 30?C
  • Chamber humidity 75% RH

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RGB - Quart
RGB : rusty grain beetle (Cryptolestes ferrugineus)

  • 400 g whole wheat (2/3 jar)
  • 200 g crimped wheat (1/3 jar)
  • 1/4 tsp wheat germ (#40)
  • 1/4 tsp brewers yeast
  • All mixed
  • Old jar sifted w/ #14 & #40 sieve (once a week)
  • Contents of #40 sieve (adults) put on new media
  • Grain and fine materials returned to old jar
  • Record oviposition and parental dates
  • # of parental adults is 400 (0.3-0.4 ml)
  • Parental adults replaced every 2 months
  • Throw dead adults out to prevent disease
  • Parental adults should be transferred to new media once a week
  • Generation time is about30 days
  • Chamber temp. 30?C
  • Chamber humidity 75% RH
  • wheat moisture 13%

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RGB - flour - pint
RGB : rusty grain beetle (Cryptolestes ferrugineus)

  • < 1/2 pint flour (#40)
  • 1 tsp wheat germ (#40)
  • 1 Tbsp brewers yeast
  • All mixed (can make a premix)
  • Old jar sifted w/ #40 sieve (once a week)
  • Flour returned to old jar
  • Adults put on new media
  • Record oviposition and parental dates
  • # of parental adults is 100
  • Parental adults replaced every 2 months
  • Throw dead adults out to prevent disease
  • Parental adults should be transferred to new media once a week
  • Generation time is about 30 days
  • Chamber temp. 30?C
  • Chamber humidity 75% RH
  • wheat moisture < 13%

Pre-mix media for RGB

  • Divide gallon of flour in half, add 10 Tbsp of brewer's yeast and 10 tsp wheat germ to each, then mix well.

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C. waterstoni (host: RGB) - gallon (continuous culture)

  • Add 1/2 Quart of 3 to 4-week-old RGB culture to top of gallon jar
  • When gallon is full, sift w/ #14, #40, #70 sieves to retrieve wasps
  • Put recovered wasps on 1/2 Quart of 3 to 4-week-old RGB culture, in new gallon jar
  • Feed weekly

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C. waterstoni (host: RGB) - pint

  • Use #40 to sift out late instar (4th) larvae from 3-4 week old RGB (C.f.) jar
  • Put 50-60 of these larve into 1 inch of wheat, in pint
  • Old jar of C. waterstoni sifted w/ #14, #40, & #70 (don't bother cocooned materials)
  • Return everything, or at least cocoons
  • Adult wasps added to RGB larvae
  • Add rehydrated raisin
  • Record oviposition and parental dates
  • Oviposition time is 10 (9-14) days
  • Seed number is 20 wasps
  • Supplement wasps as needed with new wasps
  • Sift wasps gently
  • Wasps are quick and clingy - be alert and quick, but gentle
  • Generation time is 14-19 (most 16) days
  • Chamber temp. 30?C
  • Chamber humidity 75% RH

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STGB - pint (method 1)
STGB : sawtoothed grain beetle (Oryzaephilus surinamenis)

  • Fill pint with crimped wheat
  • 1 tsp brewers yeast
  • All mixed
  • Old jar sifted w/ #14 & #40 sieve (once a week)
  • Oats and fine material returned to old jar
  • Adults put on new media
  • Record oviposition and parental dates
  • # of parental adults is 100
  • Parental adults replaced every 2 months
  • Throw dead adults out to prevent disease
  • STGB are good climbers - watch closely
  • Parental adults should be transferred to new media once a week
  • Generation time is 3-4 weeks
  • Chamber temp. 30?C
  • Chamber humidity 75% RH
  • wheat moisture 13%

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STGB - pint (method 2)
STGB : sawtoothed grain beetle (Oryzaephilus surinamenis)

  • 1/2 pint crimped wheat
  • 1/2 pint rolled oats
  • 1 tsp brewers yeast
  • All mixed
  • Old jar sifted w/ #14 & #40 sieve (once a week)
  • Oats and fine material returned to old jar
  • Adults put on new media
  • Record oviposition and parental dates
  • # of parental adults is 100
  • Parental adults replaced every 2 months
  • Throw dead adults out to prevent disease
  • STGB are good climbers - watch closely
  • Parental adults should be transferred to new media once a week
  • Generation time is about 3-4 weeks
  • Chamber temp. 30?C
  • Chamber humidity 75% RH
  • wheat moisture 13%

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C. tarsalis (host: STGB) - pint

  • Use #14 & #40 to sift out late instar (4th) larvae from 2-3 week old STGB (O.s.) jar
  • Put 50-60 of these larve into 1 inch of wheat, in pint
  • Old jar of C. waterstoni sifted w/ #14, #40, & #70 (don't bother cocooned materials)
  • Return everything, or at least cocoons
  • Adult wasps added to STGB larvae
  • Add rehydrated raisin, honey water or sweetened cotton
  • Record oviposition and parental dates
  • Oviposition time is 10 (9-14) days
  • Seed number is 20 wasps
  • Supplement wasps as needed with new wasps
  • Sift wasps gently
  • Wasps are quick and clingy - be alert and quick, but gentle
  • Generation time is 14-19 (most 16) days
  • Chamber temp. 30?C
  • Chamber humidity 75% RH

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C. tarsalis (host: STGB) - gallon (continuous culture)

  • Add 1/2 Pint of 2 to 3-week-old STGB culture to top of gallon jar
  • When gallon is full, sift w/ #14, #40, #70 sieves to retrieve wasps
  • Put recovered wasps on 1/2 Quart of 2 to 3-week-old STGB culture, in new gallon jar
  • Feed weekly

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