1. 粮农技术与工程系列讲座 Series of Lectures on Grain & Agriculture Technology and Engineering HE NAN UNIVERSITY OF TECHNOLOGY

2. 粮食经济理论与政策 The theory and policy on the economics of grain 讲解人：戴晓鹂 HE NAN UNIVERSITY OF TECHNOLOGY 储粮害虫与粮食损失 Insect pests and their loss to stored grain 讲解人：王殿轩

3. 3 What are stored product insect pests? Insects Beetles (approx. 60-70 species) Moth (approx. 10-17 species) booklice (approx. 7-10 species) Mites (approx. 10 species) （ 110species in China ） Rodents or Mice Birds c.adler@bba.dec.adler@bba.de refered

4. Loss caused by insect generally A major concern with the presence of insects is potential to vector disease organisms. Many stored-grain insects possess hairs and indentations on their exoskeletons that can act as mechanical vectors of pathogens. Maize weevils have been shown to carry numerous fungi species, including A. niger, A. glaucus, A. candidus, Penicillium islandicum, P. citrinum, Paecilomyces, Acremonium, Epicoccum, F. semitectum, and yeasts (Smalley 1989, Dix 1984). Association with other fungi or fungal toxins has been found in other stored product insects including lesser mealworm and confused flour beetle with zearelenone (Eugenio et al. 1970) and confused flour beetle with F. graminearum and F. tricinctum (Wright 1973). 4

5. Loss caused by insect generally(2) The most favorable grain moisture range for stored-grain insects is from 12 to 18%. In many cases, insect infestation amplifies mold problems in grain by exposing otherwise hidden endosperm surfaces to molds, transporting mold spores to new areas, and encouraging mold germination in microhabitats made moist by insect metabolic activity (Sinha and Wallace 1966). Insect and mold metabolic activity can raise grain temperatures to 43 ⁰ C. 5

6. Some insects damage grain by developing inside kernels, feeding on the inner endosperm, and producing holes in the kernel through which adults exit. The entire life cycle (egg, larva, and pupa) takes place inside the kernel, and the insect can survive only when whole kernels are present. These insects are known as internal feeders or primary pests. Examples of internal feeders include maize weevil, rice weevil, granary weevil, lesser grain borer, bean weevil, cowpea weevil, and larvae of Angoumois grain moth. 6 Loss caused by insect generally(3)

7. 7 l Weevils on cereals Whole grain feeders Sitophilus zeamais Motschulsky Sitophilus oryzae (linnaeus) Sitophilus granarius (Linnaeus) Both larvae and adults will feed upon grain. Heating of grain also occurs in turn accelerating development of the insects and making the commodity liable to caking, moulding and even germination.(depon on the scale of bulk) Some idea of the huge numbers of weevils that can be generated is provided by the results of one study in which, 5 weeks after wheat was infested with larval forms, adults were seen to be leaving the grain at a rate of 100 per kg per day..

8. 8 Weevil damage Grain weevils will also attack other hard cereal products, e.g. macaroni and spaghetti. Granary weevil infestations can result in the reduction in the weight and quality of grain. The grain can also be tainted with white, dusty excreta which contaminate the product as well as render it unpalatable.

9. 9 June: 1 July: 25 August: 325 September: 4000 quick development of weevils

10. 10 Loss increases sharply after 2-3 weeks of egg infestation(HAUT,2009) Loss caused by weevil with time going

11. Rice weevils can fly and easily distribute themselves throughout a storage facility. Because of their flight ability, they may also infest grain while it is still standing in the field, especially if the harvest is delayed and the temperatures are mild. 11 Infesting ability of rice weevil

12. 12 Lesser grain borers infest all types of cereal grains, but prefer wheat, corn, or rough and brown rice. Tropical in origin, possibly from the Indian subcontinent, they also feed on peanuts, nuts, birdseed, cocoa beans, and beans as well as processed products such as macaroni, tobacco, and dried spices. They do well in the flour created by the initial infestation of beetles. Grain infested with lesser grain borer has a characteristic sweet and slightly pungent odor. Rhizopertha dominica (Fabricius) Lesser grain borer

13. 13 The ability to move deep within the grain mass and the cryptic feeding within the kernels make the early detection of R. dominica difficult. R. dominica is the major cause of insect damaged kernels (IDK). Insect damaged kernels are characterized by irregularly shaped holes ( ∽ 1 mm diameter) of increasing depth that extends from the point of larval entry, around the edge of the kernel to the pupation chamber (Breese, 1960). Other signs of IDK include the presence of live insects, as well as other grain quality factors.

14. 14 Grains infested by R. dominica have a characteristic sweetish odor, which is due to the male-produced aggregation pheromones (Khorramshahi and Burkholder, 1981). The larvae and adult R. dominica feed on both the germ and endosperm and are capable of reducing wheat kernels to the pericarp (Winterbottom, 1922; Campbell and Sinha, 1976).

15. Adult feeding activities produce large amounts of frass, most of which consists of ovoid granules of apparently undigested endosperm mixed with a finer floury part (Breese, 1960). The frass contain larvae exuvae, feces, fragments of immature insects, and other by-products, which could affect the end-use quality of the infested grain (Sanchez-Marinez et al., 1997; Seitz and Ram, 2004; Park et al., 2008). 15

16. Rhyzopertha dominica could move down into the grain mass to a depth of 2 m in flat warehouse in winter in north part of China. It cause spot heat in grain mass Which is difficulty to control 16

17. 17 It has been found in cracked grain, whole-wheat flour, graham flour, cornmeal products, dried fruits, shelled nuts, raisins, dried apple, peanuts, chocolate, powdered milk, bird seed, biscuits, bread meal, breakfast foods, cereals, corn meal, corn starch, cookies, crackers, dry dog and cat food, flour, garden seeds, and red peppers. Indian meal moth Plodia interpunctella

18. 18 As the developing larvae move about, they spin a continuous strand of thin webbing. Over time, this webbing extends throughout the infested material. In a heavy infestation the webbing becomes dense enough to be easily visible. This webbing spoils more food than larval consumption. Indian meal moth

19. 19 They commonly attack tropical grains (e.g., maize, paddy, sorghum) before harvest. This insect is particularly damaging to whole grain kernels since its larva bores into and devours the endosperm and germ of the kernel. Angoumois grain moth Sitotroga cerealella

20. 20 The larger grain borer usually is restricted to corn (maize). It is a serious pest of dried grains especially maize and dried cassava in West Africa.maize cassavaWest Africa It is believed that this beetle was introduced into West Africa through food aids from America. It reached Africa through Tanzania in the early 1970s. Tanzania It is extremely damaging to maize when dried and stored on the cob. There is no any larger grain borer in China up to now Larger grain borer Prostephanus truncatus

21. 21 Both adults and larvae feed internally on maize grains and an infestation can start in the field (when the cob is still on the plant) but most damage occurs in storage.larvae Larger grain borer Prostephanus truncatus

22. Cowpea weevil Callosobruchus maculatus (F) They infest stored legumes, including cowpeas (black-eyed peas), dried peas, chickpeas, lentils. These crops bring in more than 90 million dollars into the U.S. economy for the 1 million metric tons harvested each year. Tropical and subtropical in origin, they are commonly associated with legumes both in the field and in stored and packaged beans worldwide. They do not infest other cereal grains. 22 Bean borer

23. 23 All types of beans (kidney, lima, green, snap), peas, lentils as well as some other seeds in storage are attacked. Heavily infested peas are often reduced to shells. The larvae feed within the beans as they mature. While only a small dot-like spot marks the larva's entry hole, the beetle's exit is through a neat circular hole. There is no any larger grain borer in China up to now Bean weevil Acanthoscelides obtectus

24. Other insect species develop on the cracked or broken kernels and grain dust, which can be produced by harvesting or binning procedures. They can also enter the kernel through feeding damage created by internal pests. These insects are known as external feeders, bran bugs, or secondary pests. They include Indianmeal moth, psocids, grain mites, flour beetles, saw-toothed grain beetles, flat grain beetle, rusty grain beetles, and cadelle beetle. 24 Broken grain feeders

25. 25 Under humid conditions, populations can expand quickly, causing up to 10% weight loss (Opit et al. 2011), although they are generally thought to be a secondary pest. In some situations, they may be considered a pest of medical importance because some people exhibit allergic reactions after contact with an infested commodity. When populations are high, the insects may coat the grain surface and look like a “dust” or “carpet” moving or coating the grain surface. Psocids feed on a variety of animal and plant matter, preferring processed grain products, but are just as common in most whole grains.They prefer grain that is going out of condition that contains active fungal populations and may contribute to the growth of fungal populations because of moisture and organic matter produced as populations grow. Psocid (also called booklice) Liposcelis spp

26. 26 Psocids are cosmopolitan secondary pests for stored cereals. Liposcelid specia (e.g. Liposcelis bostrychophila Badonnel) and Lepinotus reticulatus Enderlein are distributed worldwide, some of them reproduce by partenogenesis and are abundant during summer and autumn Psocids

27. 27 Presence of such insects causes undesirable contamination in stored food products. psocid produce weight and quality losses, particularly if the moisture level is high associated psocid damages with the presence of localised fungal growth which is a good food for the booklice. Psocids

28. 28 Humidity and temperature accmulating on central top surface in depth of 20-30cm after no-perfect aeration Psocids

29. Oryzaephilus surinamensis (Linnaeus) The sawtoothed grain beetle lays its eggs loosely on foodstuffs at the rate of 6–10 per day, with total being 370 per female. The larvae are to be found within the mass of the foodstuff in the top centimetre or two.larvae As mentioned above damaged cereal is entered through broken kernels, and the larvae feed on the germ, causing damage by reducing the percentage of grains which will germinate.germ 29

30. merchant grain beetle A relative of the sawtoothed grain beetle of the same genus, the merchant grain beetle, is more likely to be found in domestic dwellings since it requires higher more stable temperatures and can be found infesting biscuits and fruit and nut products.genus merchant grain beetle The adults can fly but rarely do. They can be differentiated by looking at the distance of the eye to the prothorax: with the merchant grain beetle it is less than half the vertical diameter of the eye. 30

31. These insects are often grouped together at the "flat grain beetles" or "bran bugs." Technically they are the rusty grain beetle, Cryptolestes ferrugineus, the flat grain beetle, Cryptolestes pusillus, and the flour mill beetle, Cryptolestes turcicus. 31 Cryptolestes ferrugineus (Stophens)Cryptolestes turcicus (Grouvelle)Cryptolestes pusillus (Schonherr) Flat grain beetle

32. The rusty grain beetle has a worldwide distribution and is often found in stored. Adults are cold-hardy and fly well in warm temperatures. This insect prefers high moisture grain or moist, decaying food. It has been recorded from wheat (bran, germ, and flour), rye, corn, rice, oats, barley, oilseeds, cassava root, dried fruits, and chilies, although the preferred host is wheat and development is optimum on this grain. Larvae feed preferentially on the germ of the whole kernels, but they also feed on the endosperm and sometimes hollow out the entire kernel. They cannot attack undamaged grains, although imperfections resulting from handling may permit feeding. Developmental period is shortest and oviposition is higher as cracked grain particle size increases (Sheppard, 1936; Throne and Culik, 1989). Mold growth promotes larval development with development shortest (22 days) on Trichothecium roseum (Persoon) Link ex S. F. Grey and Fusarium moniliforme Sheldon resulting in the longest developmental period (34 days) (Sinha 1965; Arbogast 1991). 32 Rusty grain beetle Cryptolestes ferrugineus (Stephens)

33. Mold feeders are external feeders, they do not directly damage the grain through feeding. Instead, these insects contaminate the grain mass through their presence and metabolic activity. Metabolic activity generates heat and produces water through the process of condensation, which encourages mold growth and grain spoilage (Magan et al. 2003). The growth of insect populations in the vicinity of these hot spots can significantly reduce grain quality through metabolic wastes and contamination from body parts or fragments. Mold feeders usually indicate that grain is going out of condition and that some mold growth has occurred. Common mold feeders include foreign grain beetle, rusty grain beetle, hairy fungus beetle, and psocids. 33 mold feeders

34. It has a worldwide distribution and has been found in many commodities including raw grains and cereal products, peanuts, oilseeds, dried fruit, and spices. It prefers commodities that are moldy and is able to survive on mold cultures alone. It can consume several different fungal organisms, many common in stored grains (Shayesteh et al. 1989; David et al. 1974). Population development, specifically larval growth, requires high RH (92 to 75%), and none survive at 58% RH (David and Mills 1975). 34 Foreign grain beetle Ahasverus advana (Waltl)

35. It prefers to feed on mold and is a good indicator of moldy food. Adults are strong fliers and often move into grain storages, railcars and food facilities by flight. The presence of this insect is a good indicator of grain going out of condition and probably indicates that mold is present in food. They are attracted to hot spots within the grain mass, and their metabolic heat and fecal material can contribute to the heating of a grain mass (Sinha and Wallace 1966; Tsai et al. 2007). 35 Hairy fungus beetle Typhaea stercorea (L.)

36. Insects damage grain by boring holes into the kernels and reducing grain quality through weight, nutritional, or quality loss; spreading and encouraging mold germination; adding to the fatty acid content of the grain; and leaving quantities of uric acid that cause grain rancidity. While feeding, insects also create fines and broken kernels that reduce airflow through the grain when aeration fans are used. This reduction in air flow can cause an increase in temperature, compounding the problem. In addition to the direct damage, the presence of insects in a grain sample can result in cash discounts for the grain. 36 stored grain damaged by insect pests

37. Direct feeding damage results in reductions in weight, nutritional value, germination and market value. Harmful to stored grain of insect pests 37

38. 38 deterioration and contamination from the presence of Insects results in downgrading of grain and market value due to insect parts, odors, molds and heat damage The profits from producing a crop should not be allowed to waste away in storage. Harmful to stored grain of insect pests

39. 39 Insect infestation which causes damage to the grain tegument and produces carbonic acid and water, contributing to the increase of the humidity content which then causes an increase in the grain respiration and consequentially in the temperature. Harmful to stored grain of insect pests

40. 40 Granary Weevil,Sitophilus granarius Rice weevil, Corn weevil Federal Grain Inspection Service (FGIS),USDA

41. The red flour beetle attacks stored grain and other food products including flour, cereals, pasta, biscuits, beans, and nuts, causing loss and damage. It may cause an allergic response, but is not known to spread disease or cause damage to structures or furniture.allergic response The United Nations, in a recent post- harvest compendium, estimated that Tribolium castaneum & Tribolium confusum, the confused flour beetle, are "the two most common secondary pests of all plant commodities in store throughout the world."confused flour beetle 41 Tribolium castaneum (Herbst)

42. 42 They cannot feed on whole grain, but can feed on broken kernels that are usually present. In general, fungi may play a significant role in the nutrition of rust- red flour beetles. Red Flour Beetle Tribolium castaneum

43. 43 Confused flour beetles can be found infesting a variety of grain and food materials. They have been reported in grain, flour, and other cereal products, beans, cacao, cottonseed, shelled nuts, dried fruit, dried vegetables, drugs, spices, chocolate, dried milk and animal hides. They cannot feed on whole grain, but can feed on broken kernels that are usually present. In general, fungi may play a significant role in the nutrition of confused flour beetles. Confused Flour Beetle Tribolium confusum

44. 44 Mites are common pests in grain storages and mostly occur in damp or moist grain, residues, oilseeds and animal feeds. They are not readily seen because they are the size of specks of dust. Mites are not insects (which have six legs) but are related to ticks and spiders and have eight legs. Mites

45. 45 Mites multiply under high humidity conditions (over 65% relative humidity) and upper temperature limit of 35-37ºC. Under these conditions, the common mould mite completes its life cycle in 8-12 days and a maximum population growth of 500 times per month can occur. Because of their rapid growth in warm, moist conditions, they usually reach peak numbers during late summer.

46. 46 Both the mould and grain mites cause direct damage by eating the germ of the grain and spreading fungi in the commodities. Heavily infested commodity becomes tainted with off-flavours caused by squashed mite bodies when it is moved or processed. mites

47. During heavy infestation from the mould mite, the dead and live mites settle as a brownish dust layer on stacks of commodities and floors of stores and emit a lemon-flavoured odour leading to the popular name ´Lemon-scented mite´. In this situation, they can cause discomfort to workers handling infested grain and packaged commodities. The ´straw-itch mite´ 谷痒 病螨 can cause severe dermatitis 皮炎 and allergic 过敏 conditions in people handling infested commodities. Infested feedlots are also been reported to have caused feeding problems and allergic conditions in stock. The markets reject heavily infested commodities. Safe ? 47

48. 48 Some of the cereal pests have flight ability and often start the infestation in the field several weeks before the crop is harvested or when the cereal is being filled dry in stalks or in shocks. The ability of the insects to fly long distances between fields and to and from grain stores as shown below can quickly spread the infestation. Some information of Insect Pest Infestations

49. 49 《quarantine insects for P R China》 （2007-05-28） Insect 146 species （ genus ） ， 11 species （ genus ） to stored grain Acanthoscelides obtectus （ Say ）菜豆象 Bruchidius incarnates （ Boheman ）埃及豌豆象 （ non Chinese species ） Bruchus spp ．豆象属 （ non Chinese species ） and C ． maculatus （ F ．） ） Callosobruchus spp ．瘤背豆象 Caulophilus oryzae （ Gyllenhal ）阔鼻谷象 Pharaxonotha kirschi Reither 谷拟叩甲 Prostep hanus truncatus （ Horn ）大谷蠹 Ptinus tectus Boieldieu 澳洲蛛甲 Tribolium destructor Uyttenboogaart 褐拟谷盗 （ non Chinese species ） ） Trogoderma spp ．斑皮蠹属 Zabrotes subfasciatus （ Boheman ）巴西豆象

50. Thank you ！