The powderpost beetle is a common name that is applied to representatives of three beetle families of the Coleoptera that are closely related to each other, which also feed upon dry wood. And the three families that contain most of the Powderpost species are: the Bostrychidae, Anobidae and Lyctidae. They are commonly known as powderpost beetles, because of their effect upon the wood in which they work. They may reduce the entire interior wood to a fine, flourlike powder. For example, Bostrychidae (Family-Coleoptera) are economically important, they represents a highly destructive group of wood boring and stored beetles .They are most well known in the tropical areas, but they are not as important as Anobidae and Lyctidae in the temperate areas. This family consists of 650 species (Lense, 1924); which includes some of the most destructive beetles, and some of the species of this family cause large damage to stored products such as dried roots and grains. In the tropics they are especially destructive to injured felled, timber and bamboos (Satish et. al., 1998). The larvae of this family do most of the damage. Some species can kill weakened trees; others have the tendency of tunneling into the green shoots of plants. Members of the family of Bostrichidae have been widely spread through trade because of their tendency to bore into wood products such as timber and bamboo, but a few also attack conifers (Fisher, 1950).
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On the other hand, the family of the Lyctidae (Coleoptera) comprises worldwide around 70 species of small beetles which exist on dry, such as wood, bamboo, and a great variety of related products. As well as her sister family (Bostrychidae, Coleoptera) , the lyctidea are also known as powder post beetles, due to the fine flour-like powder produced by the larvae .
Heterobostrychus aequalis and Dinoderus minutus, are member of Bostrychidea- family Coleoptera) which are generally known as bamboo borers. Dinoderus minutus are considered the most important species in the family which degrades seasoned hardwoods with high starch content, it's known as powder post beetle because due the manner of this beetle which their larvae tend to reduce infested wood or susceptible timber into fine flour-like frass. (Abood et. al., 1994, 2008; Eaton & Hale, 1993; Tan et. al., 1981; Dhanarajan, 1977; Hickin, 1968; Beeson and Bhatia, 1937) .There is about 50 insect pest which attack felled culms and products made from bamboo (Satish and Wang, 1998). There are all borers and among them are 26 Dinoderus species (Shafer et. al., 1999).
The larval development period for this beetle is between 3 to 4 months. Under unfavourable conditions such as poor starch supply it may take longer than that. (Francia & Garcia, 1958). The fully develop larvae will make a chambers in which they pupate. The fully immature beetle emerges after few day and continued tunnelling until its body has sufficiently hardened before it goes out through the hole she made or from the original entrance holes, the adults emerge out through the external rind just above their pupae chambers (Ho, 1998, Satish et. al., 1994).
On the other side, the Heterobostrychus aequalis (Waterhouse), it's one of the major beetles that attack timber in Malaysia; it harms trees, wood, bamboos and its product as well as building materials, and it has great threaten to forestry production, domestic life and architectural safety. Heterobostrchid adult typically are 3to 6 mm long, with slender, cylindrical bodies. Their reddish-brown to black color is similar to other powderpost beetles.
The elytra are strongly punctured without hair, and it has thick lateral ridge. The male has two elongated tubercles on the upper part of the body, while females have only traced of tubercles (Booth et al., 1990). The larval development period is between three to four months in the tropical areas, whereas the life cycle usually completes within two or three months, but under certain circumstances such as bad condition, poor starch supply and so on, my take little longer than usual time, (Francia & Garcia 1958).
Several lyctidae beetles (Coleoptera) mainly attack dried bamboo timber and bamboo products. Although these species are quiet common, they cause much less damage to bamboos than bostrychid beetles. Lyctidae family is important beetle pests of seasoned hard-wood in Malaysia. A number of species of lyctids have already been documinted locally (low, 1975); namely, Minthea reticulate M. rugicollis, Lyctus discedens (Ho unpubl.), L. africanus, as well as the most dreaded species in temperate countries. Their existence in imported timbers has often been unsuspected and whenever they have a perfect condition they are quickly like to establish populations; due to that, several species are now widely distributed (Ho 1995).
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M.rugicollis of ( lyctidae Coleoptera). It was first described by Walker in 1858. This Lyctid beetles are considered important in the timber industry and is known to attack seasoned or partially seasoned wood, representing 93 species (Browne, 1919). M. rugicollis occurs in South East Asia, Australia, East Africa and the Neotropical region including some countries in the Caribbean. M. rugicollis is native to a number of tropical countries; it exists in limited population numbers in humid natural forests. It most likely leads an unstable existence, living on the dry sapwood of fallen trees (Browne 1939).and it also attracted little attention in the natural environment whereas it plays a vital role in the degradation of timber and other cellulosic plant materials that have a lower moisture contents (Abood & Murphy 2006).
The larvae of this species tunnels into the wood and it reduces the wood to a fine powder, the adult galleries are empty but the larval tunnels are tightly packed with fine dust. Damage caused by M. rugicollis is evidenced by small piles of frass that can be collect on the surface of infested timber with the emergence holes. The growth time for the larvae differs from 2-12 months it depends on the weather conditions. Then the fully grown larvae tunnel towards the wood surface and open small oval cells where the pupation happens, two to three weeks later mature beetles emerge making round holes in the infested wood (Browne, 1919, Anon, 1957)
On other hand, L.africanus of Lyctidae, Coleoptera, insect attacks the sapwood of wide-pored hardwoods in worldwide, Long known from the Ethiopian and oriental regions and nowadays distributed throughout the world in different regions. Today it remains uncertain whether the origin of L. aficanus is African or Southeast Asian. It was introduced into countries of the southern and eastern Mediterranean (Morocco, Egypt), in earlier times; and recently, a number of of the species has been introduced into modern industrial countries (North America, Europe). Lyctus africanus (Lesne) is the commonest species widely distributed by throughout the trade. India. It is one of the most important insect pest attacking logs, branch wood and practically every kind of manufactured wooden article that contains sapwood (Beeson 1961). For instance, in India many short rotation and alternate timbers that have being used for making many finished products .The existence of starch which containing sapwood makes these products very susceptible to insect borer attack like Lyctus africanus.(Coleoptera ,Lyctidae).
To describe the pupal development and adult lifespan of (H, aequalis Dinoderus minutes, L. africanus, M .rugucollis (Coleoptera: Bostrychidae, Lyctidae).
To describe the sexual differences in pupal stages of the 4 species.
To identify morphological characteristics in different pupal stages of the 4 species.
Duration of the pupal stage of the 4 species.
Mortality between pupal to adult stage.
Lifespan of adult stage male vs. female
The powderpost beetles can be serious pests of forestry and wood-based industries in the world wide, and they play a vital role in the destruction of the wood-based products; and some species of powderpost beetles are considered one of the major pest that attack on bamboo and wood. Although there are some researches that have been done on these powderpost beetle species, in terms of determining the sexual and morphological differences in the adult stages; the information regarding on the development and morphology characteristics in the pupal stages is missing.
This study is conducted to grant more information on the powderpost beetles especially in the morphological characteristic and how to determine the sexual differences and the development in the pupal stages of the four powderpost beetles species namely known as (H. aequalis D. minutes, (Coleoptera: Bostrychidae) and L. africanus, M. rugucollis (Coleoptera, Lyctidae). to provide more information concerning these powderpost beetles in order to get efficient prevention or controlling methods in the future.
IMPORTANTANCE OFPOWDERPOST BEETLES
Powderpost beetles are the most important borer beetles that degrade seasoned hardwood which have high starch contents, According to Cummins and Wilson (1939), they mentioned that, the destruction of sapwood of commercial timbers that caused by the Lctidae beetles are the matter of economic importance through the world because these insects causes losses of totaling millions of dollars worth (William,1991). The pest status of Minthea rugicollis on Heavea brasiliensis (rubberwood) is considerable interest due the importance of this wood as a timber resource over the world in recent years. While there is undoubtedly potential in the ready availability of the rubberwood, it has been also recognized as highly susceptible to M.rugicollis (Norhan, 1981 et. al., 1985; Abood et. al., 1992).
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The damage caused by the M. rugicollis which happen in plywood tea-chets in java; M. rugicollis tends to make galleries on the surface of the infested plywood panels in contact and more extensively then the other species of the Lctidea family. It also bores lead tinfoil linings of the tea- chests (Kalshiven, 1923). Lyctidae family is considred the most dominant Powderpost beetles in Peninsular Malaysia that attack the sapwood of many species. For instance in Philippine, Francia and Garcia mentioned (1958) mentioned that the species occurrence in the domestic premises, sawmills, lumberyards and timber factories. They normally attack the wood products, bamboo, and rattan, which are the main parties that have economic importance, this species are also considered as an important pest of seasoned wood products in Brazil (Zanoto et. al., 1985) and China (Shi and Tan 1987).
Cummins and Wilson (1934), reported that, the Lyctus beetles attack the over commercial timber sapwood caused a lot of destruction and highly correlated to the economic importance in all over the world and mostly in the tropical areas. Goods that have been produces from the commercial timber species which are susceptible to the attack of these insect are relatively decreasing the quality and the value of these products in the competing market (Sukartono, 1983).
Bostrychidae beetles are also considerable as a economic pest to the to the forest and wood based industries (Rai & Chatterjee, 1963), and only some species have become important pests of timber, wooden in tropical countries ( Hickin, 1975). Bostrychidae are among those beetles which perfectly adapted and they don't have specific host some of them they prefer a particular host. For instance, some of Dinoderus species normally breed only in bamboos (Beeson & Bhatia 1937). Due to the wide range of host plants, Bostrychidae become an important economic pest of stored cereal, dead wood or wooden products and sometimes can harm the living trees.
DISTRIPUTION OF POWDERPOST BEETLES
The powderpost beetles are widely distributed in the world; and each geographical region in the world has its own indigenous as well as introduced species. They are only absent on ice sheets of the Antarctic Continent and Greenland due to the low levels of thr temperature. For example, out of the 66 species known in the world, there are 10 of them living in the United States of America and 6 of them are serious pests (Fox and Ruff, 2004). In South East Asia and specially Malaysia Lyctids are considered the second and most important beetle after termites in terms of wood and wood products destructiveness which they target to large-pored hardwoods such as mahogany, hickory and bamboos.
Furthermore, M. rugicollis, family of Lyctidae - Celeptera; is widespread in tropical and subtropical regions. It has been reported from Australia, Java, Africa and Neotropical regions including: French Guiana, Trinidad& Tobago, Dominican Republic and Puerto Rico. Also it occurs in the Caribbean and poses a threat to the regional timber industry in the area (Browne, 1957, Bhatia, 1994, Anonymous, 2004,).
Powderpost beetles are similar in many ways and sometimes it's very difficult to differentiate between some species of this order (Coleoptera). Lyctidae beetles are reddish black to brown and 1/32 to 1/8 inches long. Their body is elongate and flattened. The key characteristics of Lyctidae family are the two segmented antennal club. Unlike the tow other families Bostrychidea and Anobids; the head of Lyctids are visible from the above and the American scientists and taxonomists call this family as true powderpost beetle based on the damage, appearance, size of exit holes and frass characteristics that makes difference from other families. Mature larvae are C-shaped and slightly hairy, with three pairs of small legs immediately behind the head. Larvae body colour is yellowish-white and head is tan to brown (Jones, 2008).
On the other hand, Bostrichidae beetles are reddish brown to dark brown or black and 1/32 to 3/8 inches long. They are generally cylindrical with a roughened thorax. The tips of the elytra are frequently concave and pitted. The head is turned downward and is not visible when viewed from above; also the antennal club has three or four segments unlike the Lyctidae. The larva is also C-shaped grubs; however, in this family, the segment immediately behind the head is much wider than the segment near the tail.
In contrast, Anobiid beetles are reddish brown to brownish black and range in length from 1/16 to 1/8 inches. They have a slender, cylindrical body. In most species, the head is curved downward and concealed by a hoodlike pronotum and also the antennae have 11 segments. Unlike the Lyctids, anobiids reduce the wood to pellet, instead of fine powder. The most anobiidae, the head is bent downward and the eyes are not visible from above.
The larvae similar to Lyctid and Bostrychid are C-shaped and nearly white except for the darkened head capsule (DeAngles, 1995, Jones, 2008).
DAMAGE CAUSED BY POWDERPOST BEETLES
Wood become an important part of human life in recent years, the consumption and trade of forest products has increased substantially and is projected to further increase in the years ahead (Hicks, 2001). Furthermore, forests are the major source of wood products. Global demand for wood is anticipated to reach 5.6 billion m3 in 2020 (Birler, 1995). This demand cannot be met by natural forests alone. Some sources, such as commercial forest plantation resources are an Ideal alternative that may offer to close this gap between the demand and supply of wood in the domestic and international markets. However, Powderpost beetles in general attacks the dry wood and can damage a variety of wood and wood products; For instance, these beetles can damage wooden furniture, picture frames, and ornamental objects causing millions of dollars worth of damage every year around the globe.
Lyctid beetles attack only hardwoods, particularly those with large pores (vessels). The pores must be large enough for the female to insert eggs. The susceptible wood has >3% starch, which is a necessary nutrient for lyctid beetles. In native hardwoods, lyctids feed in the sapwood rather than the heartwood due to the starch content. Some of highly susceptible hardwoods include Oak and Mahogany etc; also many of the lighter-colored and low-density tropical hardwoods such as banak, luaun/meranti, obeche, etc are highly susceptible to lyctid attack. Anobiid beetles typically are more commonly encountered than lyctids or bostrichids (Jones, 2008). Powderpost beetles owe their ubiquity largely to their insidious development within a nutrient-filled protective environment that also acts as a buffer to extrinsic fluctuations.
Due to this, the lyctids tend to have a wider range of tolerance to variations in climatic conditions than would otherwise be possible (Abood & Murphy, 2006). Lyctids rarely infest wood older than 5 years. Therefore, infestations are usually in new homes or newly manufactured articles (Koehler, 1999).
Anobiids can attack both hardwoods and softwoods. However, they cause more wide damage to hardwoods than softwoods because hardwoods contain more nitrogen. Anobiid beetles cause the greatest damage to wood with a moisture content >12%, which they preferentially infest. Infestations often occur in unfinished, untreated wood in moist, poorly ventilated areas such as crawl spaces or basements of buildings, in outbuildings (garages, utility sheds, barns), or outdoors (improperly stored lumber). Because softwoods are most commonly used for building construction, structural infestations often originate in exposed softwoods in crawl spaces (DeAngelis, 1995). Also the lack of a central heating or air-conditioning system to reduce moisture levels to <12% can create favorable conditions that allow Anobiid infestations to spread upward into the walls and building interior, including furniture.
On the other side, Bostrichids are more abundant in the tropics. They attack unseasoned and seasoned hardwoods. Whereas bostrichids attack only the sapwood portion of U.S. hardwoods, they attack both the sapwood and heartwood of tropical hardwoods. Starch is an essential nutrient for bostrichid beetles. Bostrichids readily infest recently sawn, air-dried hardwood lumber with bark, firewood, and grapevine wreaths. The larger tropical bostrichid species infest packaging, veneers, furniture parts, and specialty ornamental products. The powderpost beetles also cause severe damages to the bamboo and bamboo products such as baskets, picture frames, and furniture. In general, Bostrichids do not re-infest wood after it is dry (Jones, 2008).
Powderpost beetles reduce the interior part of the wood into flour-like powder. Based on this, the damage caused by the three families can be identified through the powder they produce by the eating of the inner wood. For example, the Lyctidae family fills their galleries with very fine powder that is similar to the face powder. In contrast, the Bostrychidae family which their galleries are tightly packed with a coarser boring dust is often contains small wood fragments. On the other hand, Anobiidae family fills their galleries small pellets unlike the other two families (Jones, 2008).
Furthermore, the farss that produced by the Bostrycidae family, is not only coarser then Lyctidae and Anobiidae families; but tends to stick to gather. Even though the all beetles have common name which is "powderpost beetles" in more accurate description, the Lyctidae family is more likely to be applied the term of Powderpost Beetles; because the larva of Lyctids are the only larva among the others that produce the fine powder like dust and face powder in their galleries during the destruction of the interior wood (Arthur & Throne, 2003. Jones, 2008); so in order to avoid serious wood damage from powderpost beetles, early detection is necessary.
LIFE CYCLE OF POWDERPOST BEETLES
The life cycle of powderpost beetles is different from one family to another and it's also has been influenced by the starch content and weather conditions, mostly the temperature and relative humidity(H&R) surrounding the wood. Wood moisture and wood starch content generally is limiting factors for the life cycle of powderpost beetles. Larval development usually are very active in high nutrient wood with a moisture content >12% and at approximately 68-88Â°F and 80-90% relative humidity (RH).
The life cycle of lyctids for example, is shorter than the other powderpost beetles; because there is only one generation per year, but that generation may be completed in â‰¤3 months if it has good conditions, or in three or four years under bad conditions. The length of the life cycle naturally is one to five years for anobiids, and one year for bostrichids (Jones, 2008).
Powderpost beetles prefer to lay their eggs on bare, unfinished wood, but the placement site differs and it depending on the beetle family. For example, Anobiid eggs are usually laid on the wood surface, either in cracks or crevices or in exit holes. Unlike Anobiid, The female lyctid inserts her eggs within the wood pores. While the female bostrichids lay eggs generally in cracks or crevices on the wood surface or in bark, but several tropical species bore short tunnels in the outer sapwood of bark-free wood and lay eggs. The lifespan of Powderpost beetles are 77 days (Menon, 1957).In common with all beetles, there are four distinct stages in the life cycle: Egg, Larva, Pupa and Adult; among these stages the larval stage is the one which causes the severe damage within the wood and wood products (Koehler, 1999).
Powderpost beetles female lays their eggs in wood using a tube called an ovipositor that fits for the egg holes; but some timbers have small vessels that isn't fit for ovipositor and cannot be inserted and this kind of tree cannot be attacked by the beetles. Due to that, softwood timbers and the heartwoods of all timbers are also immune to attack by these insects. The females of powderpost beetles prefer a timber that has a high and enough starch content, because the starch content is essential for larval development. Then she lays her eggs deep in the pores of the timber. The eggs are long, cylindrical and whitish, individually laid, and each female may produce between 30 and 50 eggs. After one or two weeks the egg hatches and the young larva will start eating before boring into the wood (Kirton, 1996, Koehler, 1999).
The larvae stage is the most destructive stage in the whole life cycle of the powderpst beetles. As the egg starts to hatch the larvae starts to feed the inner wood of the host timber; they create tunnels within the timber for certain duration that can be too long or short based on the weather conditions such as temperature or relative humidity (RH). Their tunneling and development occur entirely below the wood surface. The larva little by little reduces infested timber to dust, leaving a thin layer of wood on the outside. The infested wood then crumbles at a touch. As it eats through the sapwood the larvae grows in size and leaves a fine flour-like dust, this stage takes about 2-6 months (kirton 1996). Then pupation occurs once a larva is fully grown.
When the larva is fully grown, it burrows towards the surface of the timber where it builds a special pupal chamber in which it will spend few weeks and changes into a pupa; the pupa looks like adult except certain structures that makes different from the adult due to undeveloped of those parties. The pupal period lasts several weeks or months before the adult beetle emerges through holes towards the wood surface. The exit hole may be made by the outgoing adult or by the full-grown larva it depending on the species. In the latter, the enlarged pupal chamber just below the exit hole and plug the hole with wood fibers and frass. The adult removes the frass plug and exits through the hole.
The young adult of powderpost beetles remain tunneling and keep feeding the remained wood for several days before they go to the outside world; and they are not observed because they are quite small, and they are seasonally produced and live only a few weeks after emerging. The adult beetles are most likely to be observed when they congregate around light. They fly actively, particularly in warm weather. After mating the female seeks suitable egg-laying positions and then lays her eggs and the life cycle begins again (Jones, 2008).
Factors Influencing THE Attack OF POWDERPOST BEETLES
There are several of internal and external factors that affect the life and the extent of the damage they cause the Powderpost beetles which represent a response to environmental changes that favor or inhibit the species and the structure of the wood they bore in.
Internally, there are several factors that influences the attack of the powderpost beetle include the larval activities which is depends on the availability of starch contents in the wood which also influenced by the time of year (Ho, 1994).Where the starch considered as a fundamental food for powderpost beetle. Also the chemical composition of the starch, anatomical structures, and the amount of extractives influences the extent of the damage they cause (Ho, 1994). The type of the species plays a vital role because every species is attracted to different type of wood which different composition of starch content.
The age of the host wood can also play a role. For instance, Abdul Latif et. al., (1990) mentioned that the borer attack decreases with the age of bamboo. Older bamboos have lower moisture content and an absence of starch.
Furthermore, the moisture content of the wood also has an influence on the extent of the damage caused by beetles. According to Singh (1974), the Powderpost beetles don't prefer to attack those woods which have moisture content less than 12-18%. A smoked bamboo has also shown a resistant to Powderpost beetles due to the reduction of the moisture content in the wood which was not favourable for larval survival (Gardner, 1945, DeAngelis, 1995, Jones, 2008). The density of the wood also plays a role, the wood borer seldom attack those woods which have high density in the outré layer (Liese, 1976).so it will be protected from the attack of the Powderpost beetles.
Externally, the factor that influences the attack of wood borer, can be included the falling season of the timber. For example, in Malaysia, the best time is between May and September because of the culm vulnerability is at its lowest due to the low level of the beetle population (Satish et. al., 1998). In addition to that, the temperature also influences the development time of the beetle; where it considered being longer at low rates of temperature and shorter at high temperatures. The relative humidity (RH) also has influence (Ho, 1994). The relative humidity can affect the beetle by changing the quantity of water in its body.
The culture medium that has been used to culture the four species of Powderpost beetles was Cassava (Manihot esculenta) Figure 1. Cassava plant is original to South America, the cassava has been introduces in Asia in the late 18th and 19th century by the European explorers and the early areas that has been introduced ware India, Java and Philippine. After its introduction the cassava was used as main source of food for the local people in many tropical countries (Asaoka et al., 1992). After while the cassava become a cash crop for export; today the cassava has been grown widely in the most tropical and subtropical countries.
Due to the high starch content; the cassava was suitable food to feed the four species of Powderpost beetles. In addition to that, the structure of cassava is soft and clear, and the white color of the cassava can make easy access to see the holes of entrance made by the beetles and also it can be seen clearly the insect itself. Cassava makes the job easy for the insects to inter and the breeding process inside the cassava and yet its cheaply and easily made, easy to handle and it is the most suitable media to use for this research.
Figure 1: Manihot esculenta
3.2.1 CASAVA BLOKS
The cassava blocks are made by cutting the cassava into block shape in (5cmx3cmx2cm) Figure 2. After cutting the cassava into block shape then it will but in the oven to dry for three days with different temperature levels. For instance, the first day the temperature was 60Â°C and the next day the temperature was dropped into 50 Â°C and the last day the temperature was 40Â°C. The different temperature levels have been taken in order to maintain the minimum rate of moisture content in the cassava, after that the cassava block is ready to put inside the KilnerJar.
Figure 2: cassava block
3.2.2 CASAVA PELLET
For making cassava pellets, the dry cassava was ground into powder, and this pellets will be use to observe the development of the 3rd generation that will be used the research. In order to make this pellets the same steps that were taken in making the cassava block would be taken here as well include the three days of dry with different temperature heat; for the first day 60 Â°C, and the second 24 hours the temperature will drop to 50Â°C, and the last 24 hours the temperature will be 40Â°C. After that the well dried cassava will be crushed and changed into powder; then the powder mixed with water and colour that is suitable for the quantities of the cassava to make the cassava pellets.
The colour that has been used in the cassava pellets aims to change the white colour of cassava. Since, the will be difficulties to differentiate the egg and the white cassava powder. In addition to that, the wet powder will be shaped into circular shape and dried in temperature room and after it dried the cassava pellet is ready to use.
Different Powderpost beetles of the four species ware collected from the Wood Deterioration and Control Laboratory at the Faculty of Forestry, and then the adult beetles ware removed from the old kilner jars and put new Petri dish that contains the dried cassava blocks in five to twenty pairs, based on the availability of the species to get the new generation. The new Petri dish ware kept in dark and temperature room of 27Â°C and 75% of Relative Humidity (RH).
OBTAINING NEWLY EMERGED ADULTS
It will take eight weeks or nine weeks to get new adults, and during this time the new Petri dish will be observed for the newly emerged adults and to do so we will break the cassava pellets and check it out if there is any newly emerged, if there is new beetles then we will separate from the parents and but in different Petri dish and if there is no new beetles the old cassava pellets will be replaced new cassava pellets.
3.3.1 INDIVIDUAL REARING METHOD
The "individual rearing method" which is using a gelatine capsule with buck cassava flour ware used. We are using this method in order to make the process of the handling the pupal more easy and more stable. Since, the pupal is very Vergil and when we observing the development is not easy to break the cassava pellets every time so the rearing method become an ideal thing to handle the pupal; each gelatine capsule will contain a single pupa and this pupa will be checked for every day in order to know if there is any development in their body.
OBSERVATION ON MORPHOLOGY CHARACTERISTICS
MORPHOLOGY CHARACTERISTICS IN PUPAL STAGE
During the development stages of the pupa, the morphological characteristics such as the length, width, weight and colour of the four species will be observed and measure within the species and between the species by using Light Microscope and Image Analyser
SEXUAL DIFFERENCES IN PUPAL STAGE
During the research the sexual differences in pupal stage will be observe in order to do so, we will examine six parties of the insects body include the head, thorax, pronotum, antennae, and elytra. In the same time will try to know the presence and the absence of the ovipositors by using an Image Analyzer, even though this can be considered very difficult due to the stage that we are dealing with which is very sensitive.
LIFESPAN OF ADULT STAGE OF THE SPECIES
The lifespan of the four species will be observed between the four species in order to know which species lives longer, and also within the species to find out; the mortality rate will be observed and the gained data will be noted.
The four species of the Powderpost beetles ware kept in 75% of alcohol in order to dry it, after that the characteristics of the species ware observed under the Light Microscope Figure 3. The parts that we ware emphasized ware the whole body include: head, thorax, pronotum, antennae, and elytra. And all the morphology characteristics that have been observed ware noted down.
Figure 3.1: Light Microscope
The measurement of width, high and length, of the four species were taken using Image Analyzer software that called NIS-Elements FÂ® and iSolution LiteÂ® .which is is a software package aimed to be utilized in laboratories, research centers, and at universities, where image analysis is needed.
Figure 3.1: Image Analyzer