Presentation on theme: "Stored-Product Insects: Biology (Continued)"— Presentation transcript:
1 Stored-Product Insects: Biology (Continued) Slide 31: The slide set is a continuation of lecture 8. In this set, you will be introduced to the biology of additional stored-product insects.
2 Cigarette Beetle, Lasioderma serricorne Stout, oval, mm longLight brown in colorElytra smooth, without striae, but with short hairs11-segmented antennae (4-10th are serrate)When disturbed adult head is concealed under pronotumSlide 32: The cigarette beetle is not a pest of whole cereal grains, but is found associated with feed materials, packaged food, and pharmaceuticals. See notes in the slide for details.
3 Cocoa, tobacco, tobacco products and processed food, oil seeds Holes in produce, and pupal cells in infested material4-6 instarsAdults live for 2-6 weeksoC, temperature limits ( days from egg-to-adult). 25% RH low endMycetomes, yeast-like structures in hindgutAdults are active fliersFemale lays 110 eggsSlide 33: See notes in the slide.
4 Drug Store Beetle, Stegobium paniceum Last 3 antennal segments are large and appear as loosely segmentedStriae on elytraLess common in tropicsChocolate, confectionary, biscuits, herbs, spices, pharmaceuticals.15-34oC at RH > 35%Adults live for daysFemale lays 75 eggsSlide 34: This species feeds on materials similar to that of the cigarette beetle. Both cigarette beetle and drug store beetle can penetrate packaged materials. See notes in the slide.
5 Slide 35: Color picture of cigarette beetle (left) and drug store beetle (right). Below, cigarette beetle is on the left (e) and drug store beetle on the right (f).
6 Sawtoothed and Merchant Grain Beetles, Oryzaephilus spp. Sawtoothed grain beetle, O. surinamensis.Merchant grain beetle, O. mercator.Foods:Stored grain, cereal products, dried fruit, oilseeds, and processed oilseeds.O. mercator - household pest of processed cereals, especially those of high oil content.Slide 36: These two closely related species have similar biologies. However, sawtoothed grain beetle is also found in stored grain, but not the merchant grain beetle. Both species do welkl on foods of high protein and oil content.
7 Slide 37: Picture of the sawtoothed grain beetle Slide 37: Picture of the sawtoothed grain beetle. Both species have the pointed teeth like projections on the pronotum.
8 Slide 38: The temple behind the eye is a key characteritic separating both the species. You have seen this character in the laboratory.
9 O. surinamensis does not develop on foods without carbohydrates. Unable to attack sound grain, but attacks grain with small lesions in pericarp.Feeds on germCannot complete development on endosperm alone.Can feed on eggs and dead adults of storage moths.Slide 39: See notes in the slide.
10 Both species have similar life histories. Eggs laid singly or in small clusters.In coarse foods, eggs are deposited in crevices; in finely ground material they are laid loosely.Instars, 3-4 (> in mercator than surinamensis).Temperature limits: 20 – 38oC.Optimum range = 30-35oC for surinamensis and oC for mercator.Low RH prevents development of only mercator.Rate of development increases with humidityFor example, for both species:At 30oC, 74% RH-- 19 days (egg-to-adult). At 12% RH,-- 24 days. Mortality > 30% at RH below 33%.Slide 40: See notes in the slide.
11 Fecundity highest at 54% RH (surinamensis) and 74% RH (mercator). Oviposition, 1 week after eclosion. Max. 2nd and 3rd week after emergence. Rate of egg laying high for 10 weeks.eggs/female (both species). RH affects length of oviposition period and no. eggs laid. At 12% RH, 52 eggs are laid.Life span of mated females: 4 – 19 weeks (12% RH and 74% RH).Adults and larvae are somewhat tolerant to cold.Slide 41: See notes in the slide.
12 Flour Beetles, Trobolium spp. 9 species.castaneum, confusum, madens, audax, destructor, anaphe, thusa, brevicorne, and parallelum.T. castaneum – warmer climates.T. confusum – cooler climates.Become established in heated facilities.T. castaneum – grain and grain products.T. confusum – flour.Peas, beans, cacao, cottonseed, nuts, dried fruit, vegetables, drugs, milk, chocolate, peanuts (only T. castaneum).Milled products are favored diets.Slide 42: These beetles prefer floury materials, and are commonly found in grain as well as in food processing facilities.
14 T. castaneum and T. confusum Differences BetweenT. castaneum and T. confusumSlide 44: Differences between the red and confused flour beetle.
15 Both species: eggs are laid singly. Tacky. Instars: 7-8. E-to-A development: see handout for T. castaneum.Slide 45: See notes in the slide.
16 Minimum: 20-22.5oC. Maximum: 37.5-40oC. Optimum = 32-35oC. Minimum, Optimum, Maximum temps. For development: 2.5oC lower for T. confusum compared with T. castaneum.Minimum: oC. Maximum: oC. Optimum = 32-35oC.Development < 1 month at 30oC.Progeny production varies with diet.Can feed on eggs and dead adults of the Indianmeal moth.Egg laying period: At 27oC, 148 (castaneum) to 235 days (confusum).No. eggs laid: eggs/female (low to high temps).Average life span = 1-2 years.Slide 46: See notes in the slide.
17 Both species can breed on seed-borne fungi Both species can breed on seed-borne fungi. Can feed on 24 species of fungi. Oviposited on 16 species. Completed development on 7-8 species.Rate of self multiplication: 1.29 at 22.5oC to 2.71 at 35oC for T. castaneum at 70% RH.T. confusum rate of increase is slightly lower than that of T. castaneum.Slide 47: See notes in the slide.
18 Cadelle, Tenebroides mauritanicus Family: Trogositidae.Adults are 5-11 mm longLarvae and adults feed on many nuts, seeds, grains and grain products.Can eat adults of R. dominica, S. oryzae, and O. surinamensis.Larval development: 69 days on corn and wheat.Eggs laid in batches (10-60). Incubation: days at 22C.Instars, 7-8. Larvae overwinter.Mature larvae burrow into soft wood and create a chamber for pupating.Can bore into hard woods.With overwintering: E-to-A = days.Slide 48: This is a seriosu pest in oriental regions, and an occasional and not so devasttaing pest here in the US. See notes in the slide.
19 Slide 49: Picture of adult and larvae, and information on development throughout the year. A slow developing insect, usually found in grain and grain products that are going out of condition, or produced in facilities made of wood.
20 Lay eggs throughout adult life (mean fecundity = 910 eggs total). Adults live for a year.Lay eggs throughout adult life (mean fecundity = 910 eggs total).2-3 generations per year.Slide 50: See notes in the slide.
21 Dermestids Family: Dermestidae. 700 species. 3 categories: breed only on animal protein (Dermestes spp.)breed on plant and animal materials (Attagenus spp., Trogoderma spp.)breed on cereals and cereal products (Trogoderma spp.).Trogoderma granarium (Khapra beetle).Serious pest of stored grain.Eradicated from US (CA, AZ, NM).Slide 51: These insects can feed on a variety of products of both and animal origin. They are also associated with bird nests. See notes in the slide.
22 Short antennae with 10-11 segments Larvae hairy; some hairs detachable Oval in shapeColored hairs on bodyShort antennae with segmentsLarvae hairy; some hairs detachableSlide 52: See notes in the slide. Picture of dermestids showing hairy bodies, that produce a characteristic pattern useful in species identification.
24 Larvae unable to penetrate intact seeds. Larvae feed on germ and endosperm.On wheat, eat only the germ.Eggs laid singly.Instars, 4-5.Optimum temp. 35C.Maximum = 40C.Develop at 23-73% RH.Adults are short-lived.They do not feed.One mating – eggs/female.Starvation: retrogressive molting.Temperature, food, population density, and genetic makeup – influences diapause.
25 Stored-Product Moths Adult wings covered with scales Coiled mouth partsLarvae – caterpillars, 3 pairs of true lesgs on thorax and 5 pairs of false prolegs on abdominal segments 3-62 families:Pyralidae – Indianmeal moth, almond mothGelechidae – Angoumois grain moth
26 Angoumois grain moth, Sitotroga cerealella Hind wings sharply pointed, and have long fringesFore wings have a dark spot distallyAdults live for 5-10 daysFemale lays 200 eggsDev C and 50-90% RHAdults are strong fliers