ºÝºÝߣshows by User: morshedpstu / http://www.slideshare.net/images/logo.gif ºÝºÝߣshows by User: morshedpstu / Wed, 13 Nov 2024 10:28:50 GMT ºÝºÝߣShare feed for ºÝºÝߣshows by User: morshedpstu Sericulture and Silk Production in BD .pptx /slideshow/sericulture-and-silk-production-in-bd-pptx/273269872 sericulture-241113102850-daa93b20
SILKWORM The silkworm is an economically important insect for producing silk, the larva or caterpillar after feeding mulberry leaves the secretion of the silk takes place. The silks are produced by labial glands, which are composed of a few tens or hundreds of large polyploidy cells that secrete polymerizing proteins. (i) Adult The adult silk moth is a creamy white moth that has a flat body and a wing expanse of about 5 cm. It takes no food and seldom attempts to fly. It lives for only 2 to 3 days. After mating, the female moth lays 300-500 eggs on leaves of the mulberry tree. (ii) Eggs The eggs are round and yellowish-white, and they become grey as hatching time approaches. (iii) Larvae The newly hatched larva is about 3 mm long and somewhat black in colour. The larvae grow in size and shed their skin (moult) four times. Each growing stage of the caterpillar consumes lot of mulberry leaves. The last stage full grown larva is about 7 cm long. It has a hump behind the head and a spine-like horn at the tail end. When full grown, the mature larva stops feeding, climbs on a twig and spins a cocoon. (iv) Pupa The full grown larva pupates inside the cocoon – In about 10 days time it transforms into a winged adult. The adult moth makes an opening in the cocoon and escapes through it. The cocoon The cocoon is formed from a secretion from two large silk glands (actually the salivary glands), which extend along the inside of the body and open through a common duct on the lower lip of the mouthparts. The larva moves the head from side to side very rapidly (about 65 times per minute) throwing out the secretion of the silk glands in the form of a thread. The secretion is a clear viscous fluid, which on exposure to the air gets hardened into the fine silk fiber. The filament forming a cocoon is continuous and ranges in length from 700-1100 metres. The cocoons from which moths have emerged are called pierced cocoons. These are of low value because continuous thread cannot be obtained. Pieces are removed by instruments and spun into a thread. Rearing of silkworms Selected healthy silk moths are allowed to mate for 4 hours. Female moth is then kept in a dark plastic bed. She lays about 400 eggs in 24 hours, the female is taken out and is crushed and examined for any disease, only the certified disease- free eggs are reared for industrial purpose. The eggs are hatched in an incubator. The hatched larvae are kept in trays inside a rearing house at a temperature of about 20°C-25°C . These are first fed on chopped mulberry leaves. After 4-5 days fresh leaves are provided. As the larvae grow, they are transferred to fresh leaves on clean trays, when fully grown they spin cocoons. Diseases 􀂾 Pebrine: Pebrine is also known as pepper disease or corpuscle disease. The disease is caused by a sporozoan, Nosema bombycis (family Nosematidae). The main source of infection is food contaminated with spores. Infection can be carried from one larva to another by the spores...]]>
SILKWORM The silkworm is an economically important insect for producing silk, the larva or caterpillar after feeding mulberry leaves the secretion of the silk takes place. The silks are produced by labial glands, which are composed of a few tens or hundreds of large polyploidy cells that secrete polymerizing proteins. (i) Adult The adult silk moth is a creamy white moth that has a flat body and a wing expanse of about 5 cm. It takes no food and seldom attempts to fly. It lives for only 2 to 3 days. After mating, the female moth lays 300-500 eggs on leaves of the mulberry tree. (ii) Eggs The eggs are round and yellowish-white, and they become grey as hatching time approaches. (iii) Larvae The newly hatched larva is about 3 mm long and somewhat black in colour. The larvae grow in size and shed their skin (moult) four times. Each growing stage of the caterpillar consumes lot of mulberry leaves. The last stage full grown larva is about 7 cm long. It has a hump behind the head and a spine-like horn at the tail end. When full grown, the mature larva stops feeding, climbs on a twig and spins a cocoon. (iv) Pupa The full grown larva pupates inside the cocoon – In about 10 days time it transforms into a winged adult. The adult moth makes an opening in the cocoon and escapes through it. The cocoon The cocoon is formed from a secretion from two large silk glands (actually the salivary glands), which extend along the inside of the body and open through a common duct on the lower lip of the mouthparts. The larva moves the head from side to side very rapidly (about 65 times per minute) throwing out the secretion of the silk glands in the form of a thread. The secretion is a clear viscous fluid, which on exposure to the air gets hardened into the fine silk fiber. The filament forming a cocoon is continuous and ranges in length from 700-1100 metres. The cocoons from which moths have emerged are called pierced cocoons. These are of low value because continuous thread cannot be obtained. Pieces are removed by instruments and spun into a thread. Rearing of silkworms Selected healthy silk moths are allowed to mate for 4 hours. Female moth is then kept in a dark plastic bed. She lays about 400 eggs in 24 hours, the female is taken out and is crushed and examined for any disease, only the certified disease- free eggs are reared for industrial purpose. The eggs are hatched in an incubator. The hatched larvae are kept in trays inside a rearing house at a temperature of about 20°C-25°C . These are first fed on chopped mulberry leaves. After 4-5 days fresh leaves are provided. As the larvae grow, they are transferred to fresh leaves on clean trays, when fully grown they spin cocoons. Diseases 􀂾 Pebrine: Pebrine is also known as pepper disease or corpuscle disease. The disease is caused by a sporozoan, Nosema bombycis (family Nosematidae). The main source of infection is food contaminated with spores. Infection can be carried from one larva to another by the spores...]]> Wed, 13 Nov 2024 10:28:50 GMT /slideshow/sericulture-and-silk-production-in-bd-pptx/273269872 morshedpstu@slideshare.net(morshedpstu) Sericulture and Silk Production in BD .pptx morshedpstu SILKWORM The silkworm is an economically important insect for producing silk, the larva or caterpillar after feeding mulberry leaves the secretion of the silk takes place. The silks are produced by labial glands, which are composed of a few tens or hundreds of large polyploidy cells that secrete polymerizing proteins. (i) Adult The adult silk moth is a creamy white moth that has a flat body and a wing expanse of about 5 cm. It takes no food and seldom attempts to fly. It lives for only 2 to 3 days. After mating, the female moth lays 300-500 eggs on leaves of the mulberry tree. (ii) Eggs The eggs are round and yellowish-white, and they become grey as hatching time approaches. (iii) Larvae The newly hatched larva is about 3 mm long and somewhat black in colour. The larvae grow in size and shed their skin (moult) four times. Each growing stage of the caterpillar consumes lot of mulberry leaves. The last stage full grown larva is about 7 cm long. It has a hump behind the head and a spine-like horn at the tail end. When full grown, the mature larva stops feeding, climbs on a twig and spins a cocoon. (iv) Pupa The full grown larva pupates inside the cocoon – In about 10 days time it transforms into a winged adult. The adult moth makes an opening in the cocoon and escapes through it. The cocoon The cocoon is formed from a secretion from two large silk glands (actually the salivary glands), which extend along the inside of the body and open through a common duct on the lower lip of the mouthparts. The larva moves the head from side to side very rapidly (about 65 times per minute) throwing out the secretion of the silk glands in the form of a thread. The secretion is a clear viscous fluid, which on exposure to the air gets hardened into the fine silk fiber. The filament forming a cocoon is continuous and ranges in length from 700-1100 metres. The cocoons from which moths have emerged are called pierced cocoons. These are of low value because continuous thread cannot be obtained. Pieces are removed by instruments and spun into a thread. Rearing of silkworms Selected healthy silk moths are allowed to mate for 4 hours. Female moth is then kept in a dark plastic bed. She lays about 400 eggs in 24 hours, the female is taken out and is crushed and examined for any disease, only the certified disease- free eggs are reared for industrial purpose. The eggs are hatched in an incubator. The hatched larvae are kept in trays inside a rearing house at a temperature of about 20°C-25°C . These are first fed on chopped mulberry leaves. After 4-5 days fresh leaves are provided. As the larvae grow, they are transferred to fresh leaves on clean trays, when fully grown they spin cocoons. Diseases 􀂾 Pebrine: Pebrine is also known as pepper disease or corpuscle disease. The disease is caused by a sporozoan, Nosema bombycis (family Nosematidae). The main source of infection is food contaminated with spores. Infection can be carried from one larva to another by the spores... <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/sericulture-241113102850-daa93b20-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> SILKWORM The silkworm is an economically important insect for producing silk, the larva or caterpillar after feeding mulberry leaves the secretion of the silk takes place. The silks are produced by labial glands, which are composed of a few tens or hundreds of large polyploidy cells that secrete polymerizing proteins. (i) Adult The adult silk moth is a creamy white moth that has a flat body and a wing expanse of about 5 cm. It takes no food and seldom attempts to fly. It lives for only 2 to 3 days. After mating, the female moth lays 300-500 eggs on leaves of the mulberry tree. (ii) Eggs The eggs are round and yellowish-white, and they become grey as hatching time approaches. (iii) Larvae The newly hatched larva is about 3 mm long and somewhat black in colour. The larvae grow in size and shed their skin (moult) four times. Each growing stage of the caterpillar consumes lot of mulberry leaves. The last stage full grown larva is about 7 cm long. It has a hump behind the head and a spine-like horn at the tail end. When full grown, the mature larva stops feeding, climbs on a twig and spins a cocoon. (iv) Pupa The full grown larva pupates inside the cocoon – In about 10 days time it transforms into a winged adult. The adult moth makes an opening in the cocoon and escapes through it. The cocoon The cocoon is formed from a secretion from two large silk glands (actually the salivary glands), which extend along the inside of the body and open through a common duct on the lower lip of the mouthparts. The larva moves the head from side to side very rapidly (about 65 times per minute) throwing out the secretion of the silk glands in the form of a thread. The secretion is a clear viscous fluid, which on exposure to the air gets hardened into the fine silk fiber. The filament forming a cocoon is continuous and ranges in length from 700-1100 metres. The cocoons from which moths have emerged are called pierced cocoons. These are of low value because continuous thread cannot be obtained. Pieces are removed by instruments and spun into a thread. Rearing of silkworms Selected healthy silk moths are allowed to mate for 4 hours. Female moth is then kept in a dark plastic bed. She lays about 400 eggs in 24 hours, the female is taken out and is crushed and examined for any disease, only the certified disease- free eggs are reared for industrial purpose. The eggs are hatched in an incubator. The hatched larvae are kept in trays inside a rearing house at a temperature of about 20°C-25°C . These are first fed on chopped mulberry leaves. After 4-5 days fresh leaves are provided. As the larvae grow, they are transferred to fresh leaves on clean trays, when fully grown they spin cocoons. Diseases 􀂾 Pebrine: Pebrine is also known as pepper disease or corpuscle disease. The disease is caused by a sporozoan, Nosema bombycis (family Nosematidae). The main source of infection is food contaminated with spores. Infection can be carried from one larva to another by the spores...
Sericulture and Silk Production in BD .pptx from morshedpstu
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Agricultural Botany]]>
Agricultural Botany]]> Fri, 06 Feb 2015 00:05:20 GMT /morshedpstu/plant-growth-regulators-44336419 morshedpstu@slideshare.net(morshedpstu) Plant growth regulators morshedpstu Agricultural Botany <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/plantgrowthregulators-150206000520-conversion-gate02-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Agricultural Botany
Plant growth regulators from morshedpstu
]]> 71383 24 https://cdn.slidesharecdn.com/ss_thumbnails/plantgrowthregulators-150206000520-conversion-gate02-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 https://public.slidesharecdn.com/v2/images/profile-picture.png https://cdn.slidesharecdn.com/ss_thumbnails/sericulture-241113102850-daa93b20-thumbnail.jpg?width=320&height=320&fit=bounds slideshow/sericulture-and-silk-production-in-bd-pptx/273269872 Sericulture and Silk P... https://cdn.slidesharecdn.com/ss_thumbnails/plantgrowthregulators-150206000520-conversion-gate02-thumbnail.jpg?width=320&height=320&fit=bounds morshedpstu/plant-growth-regulators-44336419 Plant growth regulators