Presentation2

Views:
 
Category: Education
     
 

Presentation Description

No description available.

Comments

Presentation Transcript

PowerPoint Presentation:

WELCOME

TOBACCO:

TOBACCO Tobacco is an agricultural product processed from the leaves of plants in the genus Nicotiana . It can be consumed, used as a pesticide and, in the form of nicotine tartrate , used in some medicines. [1] It is most commonly used as a recreational drug , and is a valuable cash crop There are more than 70 species of tobacco in the plant genus Nicotiana . The word nicotiana (as well as nicotine ) is in honor of Jean Nicot , French ambassador to Portugal, who in 1559 sent it as a medicine to the court of Catherine de Medici . Tobacco is cultivated similarly to other agricultural products. Seeds are sown in cold frames or hotbeds to prevent attacks from insects, and then transplanted into the fields. Tobacco is an annual crop, which is usually harvested mechanically or by hand.

PowerPoint Presentation:

After harvest, tobacco is stored for curing, which allows for the slow oxidation and degradation of carotenoids . This allows for the agricultural product to take on properties that are usually attributed to the "smoothness" of the smoke. Following this, tobacco is packed into its various forms of consumption, which include smoking, chewing, snuffing, and so on. Because of the addictive properties of nicotine , tolerance and dependence develop. Absorption quantity, frequency, and speed of tobacco consumption are believed to be directly related to biological strength of nicotine dependence, addiction , and tolerance. The usage of tobacco is an activity that is practiced by some 1.1 billion people, and up to 1/3 of the adult population

PowerPoint Presentation:

A. Soil insects which attack plant bed tobacco by uprooting plants, boring into stems or stalks, or feeding on roots Green June beetle larva - This large white, six-legged grub has a blackish-brown head and is about 5 cm long when fully developed. It crawls on its back on the soil surface or burrows in the soil and uproots seedlings

PowerPoint Presentation:

Mole Cricket (or changa ) ( Scapteriscus vicinus ) Mole crickets are brownish and their bodies are covered with velvety hairs, and about I 1/2 inches long (38 mm). The front legs are flattened and spadelike for digging through the soil at a rapid pace. Mole crickets eat plant roots, however, much of their damage is caused by burrowing in the soil uprooting small seedlings.

PowerPoint Presentation:

B. Insects which attack plant bed and field tobacco. 1.Insects which bore into stems or stalks or feed on roots. Tobacco flea beetle larva ( Epitrix hirtipennis ) - This white, 12-segmented larva, 4.3 to 4.8 mm long when fully developed, has a brownish head, three pairs of legs near the head, and a proleg on the last abdominal segment. It may kill newly set plants by feeding on roots or tunneling in the stalk.

PowerPoint Presentation:

2.Insects damaging leaves by sucking sap . Green peach aphid - This aphid is a soft-bodied, pear-shaped, winged or wingless insect about 2.0 mm long with a pair of long cornicles (tailpipe-like appendages) at the end of the abdomen. The adult has a pale yellow, green, or yellowish-green abdomen with a dark, dorsal blotch; the nymph resembles the adult but is light green and never winged. Both life stages damage plants by sucking sap from leaves, causing curled, stunted, distorted leaves, contaminated with honeydew and sooty mold fungi.

PowerPoint Presentation:

Chewing insects damaging leaves or stems. a.Beetles - These insects have hard, shell-like forewings (wing covers or elytra) which meet in a straight line down the middle of the back . They may or may not be able to fly. 1. Tobacco flea beetle - This very small (about 1.5 mm long), oval, black, jumping beetle chews small round holes in leaves giving them a " shothole " appearance.

PowerPoint Presentation:

Vegetable weevil - About 6.4 mm long, this brown, snout beetle has a light, V-shaped mark on its wing covers. It attacks seedlings and newly set plants feeding on both leaves and buds, leaving irregular holes.

PowerPoint Presentation:

Whitefringed beetles - Several species of these black, 11 mm-long beetles leave sawtooth cuts on the outer edges of tobacco leaves. Covered with grayish scales, each of these snout beetles has two longitudinal stripes down its back and a marginal band of long, white hairs .These beetles cannot fly.

PowerPoint Presentation:

b . Cutworms - Cutworm caterpillars have three pairs of legs near their heads and five pairs of prolegs . Several species of these thick-bodied, grayish to dark brown larvae, up to 50 mm in length, hide curled up in the soil by day and feed at night on seedlings or newly set plants in the field. They sever the stems of young plants, cut off leaves, or chew large holes in the leaves.

PowerPoint Presentation:

C. Insects which primarily attack field tobacco. Insects that feed on roots, bore into stems, or sever stems. 1.Cutworms Black cutworm, Agrotis ipsilon ( Hufnagel ) Granulate cutworm, Feltia subterranea ( Fabricius ) Variegated cutworm, Peridroma saucia ( Hubner ) Noctuidae , LEPIDOPTERA DESCRIPTION Adult - Adult black cutworm moths have dark brown forewings, white hind wings, and a wing expanse of 38 to 51 mm. Adult granulate cutworm moths have yellowish-brown forewings and a wingspan of 38 to 45 mm. The variegated cutworm moths may be yellowish or brownish with a wingspan of 38 to 50 mm. Egg - Cutworm eggs are white -- laid singly or in small clusters. Variegated cutworm eggs are generally laid in elongate patches .

PowerPoint Presentation:

Larva - Black cutworm larvae are dark greasy-gray to black, with a pale yellow line down the center of the back and three yellow lines along each side. Sometimes, however, these yellow lines are not distinct. The larvae are 38 to 45 mm long when fully developed and the skin is covered with convex, black granules. Granulate cutworm larvae are dusty brown with rough, granulated skin and up to 38 mm in length. Variegated cutworm larvae have a distinct, pale yellow dot on the mid-dorsal line of at least the first four abdominal segments. About 50 mm long when fully developed, they are a pale, dirty brown in color. Pupa - Cutworm pupae are about 20 mm in length and dark brown or mahogany in color. BIOLOGY Distribution - Cutworms are cosmopolitan in their distribution and are common in Canada and the United States. The black cutworm is more abundant in the northern portions of its range, while the granulate cutworm is more abundant southward. In North Carolina, cutworms are generally more of a problem in the Coastal Plain .

PowerPoint Presentation:

Host Plants - Cutworms attack many vegetable crops, grasses, and field crops such as tobacco, cotton, corn, and peanuts. Damage - Several species of cutworms may injure tobacco in plant beds and newly set plants in the field. Larvae hide curled up in the soil by day and at night cut off young plants near the ground and feed on the foliage. The black cutworm is one of the most destructive cutworms. One larva cuts off a plant, moves to other plants and repeats the damage. Small populations can cause considerable injury, resulting in the need to replant. Granulate and variegated cutworms also sever seedlings, but the variegated cutworm may also climb tobacco plants and feed on the leaves Life History - Cutworms overwinter as larvae or pupae. In early spring, the overwintering larvae of some species become active and feed. In other cases, moths emerge from overwintering pupae and lay eggs on host plants or other vegetation. Therefore, depending on the species, damaging cutworms found in spring may be overwintered larvae or new generation cutwormsCutworms develop through five to eight larval instars. Pupation occurs in the soil. The number of generations depends on latitude

PowerPoint Presentation:

CONTROL Since extensive damage may occur in a short period of time, plant beds and newly set plants should be inspected frequently. An economic threshold of 5 percent injured plants has been established for cutworms infesting newly set or young plants (within 3 weeks after transplanting). A bait may be used in infested plant beds or in newly set fields Ploughing fields in the early spring usually reduces cutworm populations. Scout fields for cutworm damage once or twice a week during the first month after transplanting to determine when a remedial foliar treatment is needed . For optimum control of this night feeding pest, apply a foliar insecticide in the late afternoon or early evening when 5 percent or more of the plants in a field have recent cutworm damage.

PowerPoint Presentation:

2.Budworm Tobacco budworm, Heliothis virescens ( Fabricius ) Noctuidae , LEPIDOPTERA DESCRIPTION Adult - Tobacco budworm moths are light olive to brownish-olive, with a wingspan of about 32 mm. Each forewing bears three slanted, dark olive or brown bands. Hind wings are white with dark margins. The corn earworm is usually a light yellowish-olive with a single, dark spot near the center of each forewing and a wingspan of about 38 mm. Egg - Eggs of both species are very similar in appearance – sub spherical with a flattened base, about 0.6 mm in diameter, and white or cream in color. They develop a reddish-brown band just prior to hatching.

PowerPoint Presentation:

Larva - Both species are similar in appearance. About 1.5 mm long, newly emerged larvae are yellowish-white with brown heads. With pale stripes running lengthwise on the body, fully developed larvae may be basically greenish-yellow, reddish-brown, or even black. Such larvae may be up to 44 mm long. Pupa - Shiny and reddish-brown at first, the pupae become dark brown before adult emergence . BIOLOGY Distribution - The tobacco budworm occurs throughout the Western Hemisphere ranging as far north as Canada and as far south as Argentina. The corn earworm has a similar distribution but is more abundant in cooler regions, whereas the tobacco budworm is more abundant in warmer, southern regions. Host Plants - Tobacco, cotton, and soybeans are the only cultivated crop hosts of the tobacco budworm . The corn earworm feeds on at least 16 cultivated plants.

PowerPoint Presentation:

. Tobacco is the most important host of the tobacco budworm; whereas, corn is the most important host of the corn earworm. The tobacco budworm does not infest corn, but both species are found on cotton and soybeans. Wild hosts of the tobacco budworm include deergrass and toadflax. Damage - Budworms, primarily the tobacco budworm, are important pests of flue-cured tobacco . Both species feed on tobacco leaves, but such feeding causes little appreciable damage. Damage is most serious when feeding is in the vegetative bud of the plant. The larvae often cause distorted leaves by feeding upon the tips of the leaves in the developing bud. Large holes develop from earlier feeding as the leaf tissue expands. Plants prematurely topped by budworm feeding produce profuse sucker growth. Both species of caterpillars may also bore in stalks or midribs.

PowerPoint Presentation:

Life History - Budworms overwinter as pupae in the top 5-10 cm (2-4 in) of soil. Tobacco budworm adults emerge from late April to mid-May. Corn earworm adults emerge from early May to early June. Females generally emerge earlier than males. Eggs are deposited on the leaves or buds of the tobacco plant. After hatching, larvae may first feed on the leaf and then move to the bud region. Tobacco budworm larvae have five or six instars with the development period varying from 21 to 25 days. Corn earworm development is similar. Pupation occurs in the soil. Tobacco budworm pupae enter diapause in September and corn earworms begin diapause in August. Both species have four generations

PowerPoint Presentation:

CONTROL The parasitic wasp Campoletis sonorensis (Cameron) ( Ichenumonidae ) kills small budworms while another parasitic wasp Cardiochiles nigriceps Viereck ( Braconidae ) kills large budworms near pupation. Predators include several Polistes spp. paper wasps. Several diseases, including the microsporidian Nosema heliothidis Lutz and Spendor , also reduce budworm populations. Topping plants, good sucker control, stalk destruction after harvest, and fall and winter plowing are all important cultural control practices to reduce diapausing populations. Budworms are difficult to control on tobacco prior to flowering because most of the larvae are hidden in the vegetative bud where it is difficult for insecticides to reach. A number of insecticides, however, are available to control budworms. The economic threshold level for these pests is reached when five or more plants out of 50 are infested with budworms of any size prior to buttoning. Budworms will not cause loss of any importance after the plant has buttoned.

PowerPoint Presentation:

3.Wireworm Tobacco wireworm, Conoderus vespertinus ( Fabricius ) Elateridae , COLEOPTERA DESCRIPTION Adult - Adult wireworms are the familiar click beetles. The body of the tobacco wireworm is flattened, somewhat tapered, hard, 7 to 11 mm in length, and reddish-brown with yellow markings. The southern potato wireworm adult is brownish (some are black) with tan legs and 6.0 to 8.5 mm long. Egg - Eggs of tobacco wireworm are white, spherical, and about 0.5 mm in diameter. Eggs of the southern potato wireworm are similar. Larva - Newly hatched tobacco wireworm larvae are 1.5 mm long and white. Fully developed larvae are yellowish-brown and 14 to 19 mm long. Tobacco wireworm larvae can be distinguished from southern potato wireworm larvae because the tobacco wireworm's last segment terminates in a V-shaped notch rather than in the almost closed, oval notch of the southern potato wireworm.

PowerPoint Presentation:

Pupa - Tobacco wireworm pupae are first white, but later change to reddish-brown. They are slightly larger than the adults (about 12.7 mm in length). Southern potato wireworm pupae are also slightly larger than adults and change from white to creamy yellow BIOLOGY: distribution;it is distributed in all the majoe tobacco growing areas.seen in asia.in india it is seen in karnataka,maharashtra,andhra pradesh,orissa . Host Plants - Tobacco, corn, cotton, potatoes, and other crops are hosts of the tobacco wireworm. Irish potatoes are the preferred host of the southern potato wireworm; however, newly set tobacco seedlings, roots of sweet potato, corn seedlings, and carrot are also infested. Less frequently attacked are melons, beet roots, and strawberry fruits that touch the soil surface. Damage - The tobacco wireworm and the southern potato wireworm are the most common of several wireworm species that attack the stems of newly set tobacco. Wireworms damage newly set tobacco plants by boring into and tunneling in the stalks. Some plants may be killed or stunted which results in the need to replant. The resulting irregular stand has plants of varying size and maturity.

PowerPoint Presentation:

More management problems occur with topping, suckering, and harvesting. The amount of damage varies from year to year and from field to field depending on weather, transplants, soil type, crop rotation, etc. Wireworms are more commonly a problem in Coastal Plain soils, especially if the field has not been plowed during fall and winter, or if the field was planted to a winter cover crop. However, the use of a cover crop is usually warranted in terms of erosion control. Life History - The tobacco wireworm overwinters in the larval stage . Most larvae begin to pupate in mid-May and adult beetles emerge in June and July. Eggs (average 240/female) are laid on or slightly beneath the soil surface. After hatch, larvae bore into and tunnel in the stalks of tobacco plants. the life cycle requires about 348 days (egg, 10 days; larva, 315 days; pupa, 10 days; and adult preoviposition period, 13 days). One generation occurs each year, though a very small number of larvae may survive a second winter.

PowerPoint Presentation:

CONTROL Wireworms may be controlled by a number of insecticides which should be applied and incorporated during or into the soil prior to setting tobacco plants

PowerPoint Presentation:

4.Hornworm Tobacco hornworm, Manduca sexta (Linnaeus) Spingidae , LEPIDOPTERA DESCRIPTION Adult - Adult tobacco budworm moths have a wingspan of about 112 to 127 mm, and are slate brown compared to the ash-gray color of tomato hornworms. Tobacco hornworms have size orange spots on each side of the abdomen; whereas, tomato hornworms have five similar but less distinct spots on each side. Wavy lines on the hind wings of the tomato hornworm are most distinct and jagged than the lines on the hind wings of the tobacco hornworm moth. Egg - Hornworm eggs are smooth, spherical, and about 1.3 mm in diameter. Light green at first, they turn white before hatching. Larva - Mature tobacco hornworm larvae usually have green bodies with fine, white hairs and seven diagonal stripes on each side; the posterior horn is usually curved and red. Tomato hornworm larvae have eight V-shaped markings on each side; the horn is straight and black. Both species are about 75 to 85 mm long when fully grown.

PowerPoint Presentation:

Pupa - Pupae are brown, hard, spindle-shaped, and about 50 mm long. They have a curved, pitcher-handle-like tongue case. The tongue case of the tomato hornworm is longer and more curved than the tongue case of the tobacco hornworm. BIOLOGY Distribution - The tobacco hornworm ranges from southern Canada to Argentina. The range of the tomato hornworm, however, extends only from southern Canada through the southern U.S. In North Carolina, the tobacco hornworm is more common in the Eastern and Border Belts while the tomato hornworm is more common in the Old and Middle Belts of the Piedmont. Host Plants - Tobacco is the principle host of hornworms, though other plants of the family Solanaceae are consumed, such as tomato and horsenettle .

PowerPoint Presentation:

Damage - These important tobacco pests consume large quantities of leaf tissue, particularly as fifth instars. Two or more healthy larvae can completely defoliate a tobacco plant, leaving only midribs and stem. Severe damage most commonly occurs during late July and August. Life History - Hornworms overwinter in the soil as pupae. Moths of this overwintering generation begin to emerge in early June and may continue to emerge as late as August. Nocturnal in habit, hornworm moths frequently can be seen hovering over plants at dusk. At night, eggs are deposited on the underside of leaves. Each moth deposits one to five eggs per plant visit and may lay up to 2,000 eggs. Larvae emerge about 4 days later, depending upon temperature. After feeding for 3 weeks, hornworms burrow into the soil and spend 3 weeks after which a new generation of moths emerges. Heavy egg deposition is common in August and early September due to a peak in overwintering moth emergence along with that of a second (or possibly third) brood.

PowerPoint Presentation:

. Early generations are potentially damaging to marketable tobacco. Later ones feed after harvest on noncommercial suckers. However, these last generations are important because they produce the overwintering pupae. Pupae are stimulated to enter diapause (the resting period) after the second weed of August by the shorter day lengths they encountered as larvae. CONTROL Use of cultural practices is very important. Early planted tobacco, proper (not excessive) nitrogen fertilization, sucker control, stalk destruction, and fall plowing all help to reduce overwintering populations Biological control There are a number of natural enemies that help control hornworm populations. The stilt bug Jalysus spinosus (Say) attacks hornworm eggs.

PowerPoint Presentation:

Polistes spp. Wasps prey on larvae. The braconid parasite, Apanteles congregatus (Say) lays eggs in first to third instar larvae. Offspring emerge from fourth and fifth instar larvae and spin numerous white cocoons on their backs. Bacillus sphingidis White causes hornworm septicemia disease. Two flies ( Tachinidae ) lay their eggs on hornworm larvae and the developing fly larvae kill the hornworm pupae Chemical control Hornworms should be treated with insecticides when infestations exceed the economic threshold level of 5 or more large, unparasitized larvae, 2.5 cm (1 inch) or longer, found per 50 plants. Parasitized hornworms (with small white cocoons) eat less and are counted at one-fifth of a larva. If applications are necessary during harvest, make them immediately after rather than before priming.

PowerPoint Presentation:

Tobacco Aphid, Myzus nicotianae ( Hemiptera : Aphididae ) Marks of identification Wingless and winged aphid both can be seen in the field. Winged aphids fly to plants and being producing wingless young ones called as nymphs. Wingless, aphids are soft bodied, pink to red, pale green to yellow-green, pear-shaped, and only about 1/16 inch long when full grown. Most aphids are wingless even as adults, but darker, winged forms may also be produced. Aphids have beak-like mouthparts through which they suck plant juices damage; , wingless aphids on tobacco plants are the most destructive source of infestation. High aphid populations can reduce tobacco yield by 5 to 25 percent. Aphids deposit honeydew on tobacco leaves, and a dark, sooty mold often develops. This interferes with curing and reduces quality. The presence of sooty mold indicates that aphids have been a problem, but these materials often remain on leaves after aphids have been controlled.

PowerPoint Presentation:

, a sugary substance produced by the aphids, which gives the lower leaves a shiny appearance. Economic threshold. Treatments should be initiated for aphid control when 10 of 50 plants are infested with colonies of any size. control: Aphids are attacked by the adults and larvae of several species of lady beetles, lacewings, and syrphid fly larvae, A red-colored midge Larvae also feeds on aphids after topping. A pathogenic fungus frequently controls aphids from July through September, especially in wet seasons. Although lady beetles, lacewings, and syrphid fly larvae are usually abundant on aphid-infested tobacco, they may not keep aphids below levels that will cause economic damage. insecticides include spinosad (Tracer), and methomyl (Lannate). Transplant- water and tray-drench applications of imidacloprid (Admire Pro) and thiamethoxam (Platinum) have limited direct impact on beneficials.

PowerPoint Presentation:

Whiteflies Scientific name: Bemisia tabaci Order/Family: Homoptera : Aleyrodidae Marks of identification : The tobacco whitefly Bemisia tabaci adult (bottom right) about 1 mm long. with two pairs of wings that are held roof-like over the body. They resemble very small moths. Their body is pale yellow. The body and wings are covered with a powdery, waxy coating. Whiteflies are mostly white, but can also be yellowish and some species have dark or mottled wings. They have sucking mouthparts. They are often found clustered in groups on the underside of young leaves and readily fly away when disturbed. A female may live for 60 days; life of the male is generally much shorter (9 to 17 days)

PowerPoint Presentation:

Host range: . Bemisia tabaci is the dominating whitefly in the region. Its host range includes cotton, tobacco, vegetables (tomatoes, eggplant, okra, bell peppers, cucurbits, etc.), legumes (beans, soybeans, cowpeas and groundnut), tuber and root crops (sweet potato, cassava, potato) among others. Nature of damage and Symptoms of damage : Feeding of whiteflies causes yellowing of infested leaves. Whiteflies excrete honeydew, a clear, sugary liquid. This honeydew covers the lower leaves and supports the growth of black sooty mould, which may coat the entire plant. Where plant viruses are transmitted plants show the typical symptoms of the virus diseases. Presence of whiteflies can also be recognised by a cloud of tiny whiteflies flying up when the plants are shaken. The whiteflies resettle soon on the plants.

PowerPoint Presentation:

Affected plant stages Seedling, vegetative growing and flowering stage Affected plant parts Leaves. Symptoms by affected plant part Leaves: honeydew or sooty mould. Biotypes ; There are a number of biotypes of B. tabaci and it is the B and Q biotypes that present the most risk to the UK. The B biotype, or poinsettia strain, is of major concern as it develops faster than other biotypes, producing greater numbers of off-spring. It also produces larger amounts of honeydew,has a broader host plant range, is more insecticide resistant and induces several different phytotoxic disorders in certain plant hosts (e.g. squash silver leaf disorder which affects tomatoes and cucurbits). It has been spread in trade, greatly expanding its range to include European glasshouses. Q biotype is thought to have originated from the Mediterranean region and has been associated with whitefly control problems. It is known to have resistance to pyriproxyfen, buprofezin and reduced susceptibility to the neonicotinoid insecticides imidacloprid, acetamiprid and thiamethoxam.

PowerPoint Presentation:

management: Yellow sticky boards . To use, place 1 to 4 yellow sticky cards per 300 square metre field area. Replace traps at least once a week. It is difficult to determine the population of newly trapped whiteflies on a sticky card from the previously trapped ones. Plastic covers and mulches. Preventing physical contact of the whiteflies with the plant can prevent the transmission of virus diseases. This can be done by using plastic covers and mulches and by cultural methods. Several cover crops (forage, peanut, weeds) and inert covers (silver, yellow, and white/black plastic mulches) have been shown to reduce whitefly damage. Spraying with soap and water reportedly controls whiteflies. However, care should be taken, since the use of strong soaps, or soft soaps at high concentrations can scorch the plants.

PowerPoint Presentation:

Bological control; Natural enemies Whiteflies are attacked by a large number of natural enemies: parasitic wasps (e.g. Eretmocerus spp., Encarsia spp.), predatory mites (Amblyseius spp. and Typhlodromus spp.), predatory thrips, lacewings, rove beetles and ladybird beetles. The dusty lacewing Conwentzia africana is considered to be one of the most important predators of B. tabaci . Biopesticides Neem ( Azadirachta indica ) Neem-based pesticides are reported to control young nymphs, inhibit growth and development of older nymphs, and reduce egg laying by adult whiteflies. They also reduce significantly the risk of Tomato Yellow Leaf Curl Virus transmission. Efficacy of neem-based pesticides can be enhanced by adding 0.1 to 0.5% of soft soap.

PowerPoint Presentation:

Tobacco Flea Beetle Epitrix hirtipennis ( Melsheimer ), Chrysomelidae, COLEOPTERA DESCRIPTION Adult - The adult is a hard-shelled, black, very active beetle about 1.5 mm long. Wing covers have rows of fine distinct punctures. The eyes are black and the antennae 12- segmented. Egg - The egg is very small (smaller than a pinhead), white when first laid, elongate and pointed at one end. Larva - The larva is 4.3 to 4.8 mm long when fully developed with a slender, white, 12- segmented body and brownish head. It has three pairs of short, jointed legs on the thorax and a proleg on the last segment. Pupa - The pupa is whitish with the head bent downward which is typical of pupae of the Chrysomelidae family (leaf-feeding beetles).

PowerPoint Presentation:

BIOLOGY Distribution - The tobacco flea beetle is present wherever tobacco is grown from Connecticut to Florida. Host Plants - The tobacco flea beetle is a pest of tobacco, tomato, and potato and will also attack jimsonweed and ground cherry. Damage - The tobacco flea beetle is a major pest of tobacco seedlings in plant beds and of tobacco plants in the field. Adult flea beetles damage tobacco plants from the time the plants begin growing in plant beds until harvest by chewing small, rounded holes through the leaves resulting in a "shot hole" appearance. Larvae feed on the roots of the tobacco plant and may tunnel into stalks. Large numbers of larvae may kill seedlings or severely damage newly set plants.

PowerPoint Presentation:

Life History - Adults generally overwinter in litter and trash around tobacco fields. Some may hibernate in tobacco fields if stalks were not destroyed after harvest. In early spring adults migrate into plant beds. They attack seedling and lay eggs on the soil surface beneath tobacco plants. Eggs hatch in about a week and the small, slender, white larvae feed on and tunnel in the roots and stems of tobacco plants for 4 to 5 weeks. There are three instars. After 4 to 7 days as pupae in the soil, adults emerge. With three to four generations per year, tobacco flea beetles continue to attack field tobacco until after harvest when they migrate to litter and trash surrounding the fields for hibernation.

PowerPoint Presentation:

CONTROL Control of the tobacco flea beetle in plant beds is important because the plant bed is often the source of field infestations and because healthy seedlings are important for a good crop. Trash around plant beds where beetles hibernate should be destroyed and plant beds should be covered. A braconid wasp, Microtonus epitricis ( Viereck ), is a natural enemy of the adult tobacco flea beetle. A number of insecticides are available to control the flea beetle in both plant beds and in the field when flea beetle populations reach the economic threshold which averages eight or more adults per small plant. Larger plants should be sprayed when there are 62 or more beetles per plant late in the season.

PowerPoint Presentation:

Whitefringed Beetle (larvae) ( Graphognathus spp.) Whitefringed beetle larvae are yellowish-white, legless and are tip to 1/2 inch in length (13mm) when fully grown. The entire body is whitish with the exception of the mouthparts which show as two dark brown areas. These larvae overwinter in the soil and when the tobacco is transplanted they immediately begin feeding on the plants. This feeding may result in complete destruction of the plants or a stunting if the plants are not killed. Grubs feed on the outer surface of the taproots and tunnel into the pith of newly transplanted tobacco killing or stunting the plants and causing serious yield reductions. Whitefringed beetles spread very slowly because all adult beetles are flightless female weevils. They are transported to new fields on farm equipment, water, and hay and other crops. No insecticides are currently registered for the control of whitefringed beetles on tobacco. The rotation of tobacco with good stands of grass containing few legumes or broadleaf weeds mayhelp reduce grub damage.

PowerPoint Presentation:

STORAGE PESTS: Cigarette Beetle Lasioderma serricorne ( Fabricius ),COLEOPTERA Introduction The cigarette beetle is a common insect that infests tobacco and many other stored products. It often is confused with a related species, the drugstore beetle, Stegobium paniceum (Linnaeus), which is more elongate in proportion to its width and has distinctly striated wing covers. In Pennsylvania, the cigarette beetle is an important pest of dried plant materials such as herbs, spices, and dried flowers. Description The adult cigarette beetle is a small, stout, oval, reddish-yellow or brownish-red beetle about 0.1 inch (2-3 mm) long. The head is bent down at nearly a right angle to the body, giving the beetle a humped appearance when viewed from the side .

PowerPoint Presentation:

. Cigarette beetle larvae are yellowish-white and grub-shaped, with three sets of forelegs and a brown head capsule. Cigarette beetle larvae are hairier than those of the drugstore beetle. The larvae are about 0.1 inch long when fully grown. Life History Adult cigarette beetles live 2 to 4 weeks. Adult females lay as many as 100 eggs singly on food materials. The eggs are white and oval-shaped and hatch in 6 to 10 days. After hatching, the larvae tunnel through the food material, causing destruction of the grain and contamination. They become fully grown in 30 to 50 days and enter the pupal stage, which lasts 8 to 10 days or more, depending on the temperature. Pupae are covered by a silken cocoon and bits of their food material. The entire life cycle may take from 45 to 50 days. The developmental period from egg to adult is quite variable, but typically takes 6 to 8 weeks under favorable conditions .

PowerPoint Presentation:

Damage This is the most important insect pest of stored tobacco. Package and chewing tobaccos, cigars, and cigarettes that have been attacked by cigarette beetles have holes eaten through the tobacco. Cigarette beetle adults and larvae also are omnivorous pests of other stored products. They can be found in stored grains, where they feed on debris or dead insects and damage the grain. Their main impact in households is on stored commodities, such as spices, rice, ginger, raisins, pepper, drugs, seeds, and dried flower arrangements. They even feed on pyrethrum powder strong enough to kill cockroaches.

PowerPoint Presentation:

Management Prevention and exclusion are the principal methods of controlling cigarette beetles in the home. Focus on identifying and destroying infested materials. In addition to the above-mentioned items, cigarette beetles also can be found infesting dried pet foods, old rodent baits, and flax tow stuffing in upholstered furniture. Thoroughly clean the area where the infestation was noted and apply an insecticide registered for in-home use into cracks and crevices. Exclusion is an important way of limiting the exposure of other commodities to infestation. Place pantry items in airtight hard plastic containers, including unopened items such as cake mixes, which can be infested without exhibiting outward signs of infestation.

PowerPoint Presentation:

MINOR PEST Japanese beetle - This shiny, metallic-green beetle, about 1.3 cm long, has copper-brown wing covers and six tufts of white hairs on each side of the abdomen. It chews numerous ragged holes in leaves and usually feeds gregariously.

PowerPoint Presentation:

TOBACCO INSECT MANAGEMENT Several species of insects pose serious threats to tobacco in the field, the greenhouse, and the curing barn. Insects damage the roots, destroy the leaves and buds, reduce leaf quality, and transmit several important tobacco diseases. INTEGRATED PEST MANAGEMENT Integrated pest management (IPM) combines cultural, natural, and chemical controls to maintain insect pest populations below levels that cause economic damage to the crop. IPM promotes using insecticides only when they are needed. A certain amount of insect damage does not reduce crop value enough to pay for the cost of treatment. In addition, tobacco plants often compensate for insect damage. IPM helps to maximize profits; reduce pesticide residue levels, environmental contamination, and human exposure to pesticides; and it optimizes natural control provided by beneficial organisms.

PowerPoint Presentation:

Cultural controls Several cultural practices help reduce insect infestations and decrease the need for insecticide applications. The following cultural practices aid in the management of insect pests on tobacco. 1. Plow early in the spring at least four weeks before transplanting to reduce cutworm infestations and aid in wireworm control. 2. Use recommended rates of nitrogen. Excessive rates of nitrogen fertilizer may delay maturity and make tobacco a more favorable host for hornworms and aphids after topping. 3. Adjust the transplanting date to reduce tobacco susceptibility to insect pests. Early-planted tobacco is often less favorable for aphids, splitworms , and hornworms and more favorable for budworms and flea beetles. Late-planted tobacco is highly susceptible to hornworm and tobacco splitworm damage and may have lower yield and quality. Aphids are usually most serious on tobacco transplanted near the middle of the transplanting period.

PowerPoint Presentation:

4. Destroy greenhouse transplants immediately after transplanting is completed to keep aphids and other insects from developing high populations on the transplants and migrating to the field tobacco . 5. Manage field borders to reduce insect habitat. Keep field margins clear of weeds and tall grass to reduce feeding, breeding, and overwintering sites for grasshoppers and other insects that move from these sites into tobacco fields. After tobacco is established and growing, leave uncut barriers between tobacco fields and hay fields that are heavily infested with grasshoppers. 6. Top in the early flower stage to eliminate food sources for budworms and to make the crop a less desirable host for aphids and hornworms. 7. Obtain effective sucker control to reduce food sources for hornworms, budworms, and aphids.

PowerPoint Presentation:

8. Destroy crop residues immediately after harvest is completed. Stalk cutting and root destruction reduce feeding and overwintering sites for hornworms, budworms, and flea beetles. This practice is most effective when done on a community-wide basis. 9. Plan crop rotations to reduce infestations of soil-inhabiting insects. Rotate tobacco with crops that are poor hosts of cutworms, white-fringed beetles, and wireworms. 10. Use conservation tillage to manage insect infestations. Conservation tillage, including no tillage and strip tillage, reduces aphid and flea beetle populations, but it may increase cutworm and slug infestations.

PowerPoint Presentation:

Natural Control Beneficial organisms, including predators, parasites and pathogens, provide valuable control of several insect pests. For example, parasites often kill more than 80 percent of the budworms in tobacco fields, control similar to that obtained with foliar insecticides. Hornworms are parasitized by Cotesia congregata whose larvae feed inside the caterpillars. When the larvae mature, they emerge through the backs of the hornworms and form egg-like cocoons. Tiny wasps emerge from these cocoons in a few days, mate, and seek out new hornworms to parasitize. Aphids are attacked by the adults and larvae of several species of lady beetles, lacewings, and syrphid fly larvae, A red-colored midge larvae also feeds on aphids after topping. A pathogenic fungus frequently controls aphids from July through September, especially in wet seasons.

PowerPoint Presentation:

Whiteflies are attacked by a large number of natural enemies: parasitic wasps (e.g . Eretmocerus spp., Encarsia spp.), predatory mites ( Amblyseius spp. and Typhlodromus spp.), predatory thrips, lacewings, rove beetles and ladybird beetles. The dusty lacewing Conwentzia africana is considered to be one of the most important predators of B. tabaci To preserve beneficial insects, scout fields and use economic thresholds to time insecticide applications and select insecticides with low impact on beneficials. These insecticides include Bacillus thuringiensis (Bt), pymetrozine (Fulfill), emamectin benzoate (Denim), spinosad (Tracer), and methomyl (Lannate). Transplant- water and tray-drench applications of imidacloprid (Admire Pro) and thiamethoxam (Platinum) have limited direct impact on beneficials.

authorStream Live Help