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    Showing posts with label Cotton. Show all posts
    Showing posts with label Cotton. Show all posts

    Cotton

    Cotton means, “thread”. Cotton is an in determinant plant. There are four cultivated species of cotton.

    · Gossipium arborium

    · Gossipium herbacium

    · Gossipium hirsutum

    · Gossipium barbaden

    All about cottonThe first two species are called Old-world cotton. It is grown in India, Pakistan. Lint is used in textile and stuffing. The last two species Gossipium hirsutum (American Cotton) and Gossipium barbaden (Egyptian Cotton) are grown in Pakistan and known as “Narma”. Main stem of cotton is called Cotton stick. 40 kg of cotton gives 26-27 Kg of Banola seed and 13-14 Kg of lint. Cotton is important cash crop of Pakistan. 60% of export earning is through cotton 85% domestic oil (vegetative oil) is coming from cotton. It provides raw material to 503 mills in Pakistan and 1135 ginning factories. Yield per hectare is more in Punjab than Sindh.

    PLANTING REQUIREMENT OF COTTON:

    It is warm season crop. The optimum temperature for germination is between 30-35 °C. At the time of flowering temperature is 34-36 °C.

    VEGETATIVE GROWTH PATTERN:

    Emergence of leaves from nodes takes place. Healthy root system is present for acquiring soil nutrient. Acropetal (Roots) and Basipetal (Leaves) transport system is present. Main stem is called “monopodial” and branches are called “synpodial”. Root growth is 0.5-2.0 inches each day. Cotyledon unfolds at that time root can grow up to 10 cm. At early vegetative stage root is twice than plant height. At the time of boll setting due to demand of carbohydrate root growth become slow. Root activity become slow gradually when plant mature.

    IRRIGATION:

    Cotton requires moderately to high irrigation. Cotton can not survive in stagnant water.

    SOIL REQUIREMENT AND SOIL PH:

    Clay loamy soil is best for cotton. Optimum soil pH for cotton is 5.8-6.5 (slightly acidic). Cotton can also be grown in alkaline soil (pH ranges from 8 and above). The soil should be high in organic matter.

    VARIETIES:

    The main varieties grown in Sindh are

    · Kalandri

    · M-100

    · Cris-9

    · Cris-34

    · Cris-38

    · Sarmast

    · Reshmi

    · Rehmani

    Some Punjab varieties grown in Sindh are

    · NIAB-78

    · NIAB-98

    · Krishma

    SEED VARIETY AND GERMINATION RATE:

    Seed variety should be 100% pure and germination rate is 75%. 1 lock of boll contains 6-8 seeds.

    DELITING:

    1 Kg of sulphuric acid = 10 Kg of cottonseeds.

    SOIL TEMPERATURE:

    At the time of germination soil temperature should be less than 30 ° C. Above 60° C temperatures destroy seedling emergence.

    SOWING DATE:

    Sowing starts at 15th April. Row to row spacing 2.5-3.0 ft. Plant to plant spacing 9 inches approximately.

    SEED RATE:

    8-10 Kg seeds per Acre.

    SOWING METHOD:

    Cottonseed is sown by

    · Furrow method

    · Ridges method

    In flat method 25,000-30,000 plants per acre.

    DISEASES:

    · Boll rots.

    · Nematodes.

    · Seedling disease.

    · Verticillium wilt.

    · Ascochyta blight.

    Pest threat to Sindh`s cotton crop

    Author: Mohammad Hussain Khan
    As cotton farmers in Sindh begin crop picking, they have a reason to worry: pests like mealybug, thrips and pink bollworm have started attacking patches of their farmland.
    In lower Sindh, where cotton is sown early, picking has already begun and will be in full swing soon. According to the agricultural department`s estimates, this year cotton was sowed on 575,113 hectares, against the targeted 650,000 hectares. Last year, cotton was cultivated on 584,568 hectares.
    Growers in Umerkot, Matiari and other areas claim itis mainly thrips and pink bollworm that is affecting the crop. Research officials estimate 30 per cent of the total yield in Mirpurkhas, Umerkot and Sanghar to be currently under multiple pest attacks of mealybug and pink bollworm. These are main cotton producing areas and around 50 per cent of Sindh`s cotton production comes from these districts. Mealybug and bollworm attacks have been reported in other districts as well, but on a lesser scale.Pest threat to Sindh`s cotton crop
    Research officials predict that situation could worsen if the attacks are not controlled by pesticide sprays, particularly if it rains heavily next month, as forecasted.
    `Rains can augment the crisis,` remarks an official adding that farmers should spray pesticides on the affectedportion of field and not the entire crop. Cotton growers, however, believe that sprays alone will not help them overcome the situation.
    Pink bollworm, for example, penetrates into the boll, making spray ineffective. The bollworms usually attacks the crop around September, but this year it was reported far earlier. When the crop is under the bollworm attack it makes picking difficult. According to Talpur, the pest makes boll opening difficult, prompting labourers to spend more time in picking and eventually they charge more money from farmers.
    Progressive farmers, like Mir Amanullah Talpur from Umerkot, mention a chemical pheromone that breaks the lifecycle and mating process of pest, and thus, help control attacks. However, it is not available in the market.
    According to growers, only government can ensure its availability and they showed willingness to purchase it at the market price.
    Grower Haji Nadeem Shah adds that cotton crop is also facing severe wilting and reddening due to jassid, a sap-sucking homopterous insect. He attributes this to multiple factors such as use of unknown varieties of seed, the crop being water stressed and higher temperatures.
    Even though, this occurs every season, this time round it appears to be much worse. When reddening and wilting in crop begins, it affects fruit and flower setting.
    Director General Agriculture Extension Hidayatullah Chajjro, however, argues that only `patches of fields` are under pest attacks. He insists that growers are spraying their crop as advised and that the initial field visits reports show that only 15 to 20 plants are affected in an acre which is neither dangerous, nor have caused major damage yet.
    Similarly, a group of agricultural extension officials believe that these pests are a regular occurrence every year, with attacks within threshold level. They cite water shortage and hot and humid conditions that help develop sucking complex syndrome in the crop.
    Growers, on the other hand, insist that thrips attacks are not being controlled. They fear that if the situation persists, the entire fields would be badly hit by the pest and they would get lower yields. Farmers admit that while mealybug attacks were curbed to a considerable extent in the recent past, they seem to have increased in the last couple of years.
    Source:Dawn News

    Top 10 Insect Pests of Cotton in Pakistan

    Insects represent a widely studied group of arthropods having diversity in their habitat and life forms. Adaptation of insects may be directly correlated with the successful evolution history. Scientists are working day and night to find the successful adaptation of insects to their environment. The plants on which insect feeds are called as host plants. Some insects are monophagous and feed on one plant species. Others are called as polyphagous and are having a diverse range of feeding and living. Although the pest management techniques are still proving to be reasonable to some extent but the insects are coming up with an ever increasing resistance mechanism that are supporting their life forms as well as strengthening their next generations.
    Cotton serves as a perfect host for variety of insects. Cotton is widely grown in South Asia mainly due to the perfect atmospheric and topographic features. Insect pests of cotton in Pakistan represent the greatest diversity in the whole region. More than 1300 species of insects are found attacking on Cotton crop and more than 93 insects and mites are found damaging for the cotton crop in Pakistan.

    10. Whitefly

    Insect Pests of Cotton in Pakistan: Whitefly
    Bemisia tabaci is said to be the most notorious pest of American cotton mainly due to its ability to transmit the CLCV also called as the Cotton Leaf Curl Virus. Mainly this insect pest damages the cotton crop in four ways. It sucks the cell sap and results in loss of vigor. It also injects the toxic saliva that results in a great damage to the cotton leaves. It sucks the cell sap and secretes the honey dew that invites the infestation of sooty mould. Sickly black appearance of the plant results in less absorption of sunlight and the photosynthesis process is adversely affected in one way or the other. Transmission of CLCV is one of the most important damage of cotton whitefly.

    9. Jassid

    Insect Pests of Cotton: Jassid
    Amrasca biguttula is one of the most damaging pests of cotton crop in Pakistan. Damage of Cotton Jassid is very different as compared to that of other insect pests of cotton. Cup formation of leaves is observed in the peak of its attack. It also secretes the toxic secretions that are passed along with the saliva and the plant metabolism gets a greater shock due to the very presence of this particular insect pest of cotton. It also disturbs the boll formation as the boll formation is reduced after the attack of Jassid. It also affects the ladyfinger crop and also causes a greater damage to the winter vegetables which serves as an alternate source of food when the cotton season is not in progress.

    8. Thrips

    Insect Pests of Cotton: Cotton Thrips
    Thrips tabaci is one of the most threatening pests of cotton, onion and garlic. The rasping sucking mouth parts of this insect damages the vegetative as well as the reproductive parts of many crops. In cotton the attack of thrips is greatly observed on the flowers and leaves where it congregates near the base of flowers or the leaves. Most of the farmers get the confusion in determining the attack of thrips. The mode of damage is different as compared to other insect pests of cotton. Crumpled and silvery appearance of leaves is the main sign of the thrips attack on American cotton. Insect Pest Management should be well directed in order to control the sucking as well as the chewing insect pests of cotton crop. In many countries like USA thrips is considered to be the vector of many viruses like the streak virus of peas and yellow spot of pineapple.

    7. Mealy Bug

    Insect Pests of Cotton: Cotton Mealybug
    Phenococcus gossypiphilous was first reported in 2005 in Pakistan and in 2006-07 it affected the whole cotton belt of Pakistan. Life cycle of mealy bug is very rapid and it feeds on almost all kind of vegetables and flowers mainly due to the polyphagous habit. It damages the cotton crop by sucking the cell sap and decreasing the plant vigor. It also secretes some toxic saliva secretions that inhibit the growth and disturbs plant metabolism. Sometimes it can also secrete the cottony wax and when the attack exceeds the threshold level honey dew also increases in percentage and so is the sooty mold. Chemical control is not the only solution because the biological control of mealy bug served to control most of the pest population in the Cotton belts of Pakistan. IPM of any insect should focus on all the possible methods and techniques to ensure the discouragement of pest populations in a particular habitat or area.

    6. Dusky Cotton Bug

    Insect Pests of Cotton: Dusky Cotton Bug
    Oxycarenus laetus was considered to be the minor pest of Cotton but now it is going to become the possible threat to the early and late cotton crop in Pakistan. Sucking behavior of this insect disturbs the cotton crop at early as well as the late stages. It sucks the sap from the reproductive parts of plants and it can also deteriorate the seed quality. Besides damaging the seeds and the reproductive parts it also deteriorates the lint quality resulting in poor ginning of cotton fibers. It gives the staining to the lint and the lint of low quality gets the lower price in market. It is found on cotton, ladyfinger and other malvaceous plants.

    5. Army Worm

    Insect Pests of Cotton: Cotton Armyworm
    Spodoptera litura is counted among the major insect pests of cotton crop in Pakistan. It damages the crop due to its chewing behavior. Mode of damage of armyworm is different as compared to that of other insect pests of cotton. Most important sign of its attack is the damaged leaves that are in the form of empty areas. It feeds the leaves in between the veins and the veinlets. Skeleton of the leaves dries up due to the inactivation of photosynthetic processes. This result in the loss of vigor of plant and the quality of boll is affected. Attacked fields have lower yield of bolls as compared to that of the healthy fields. IPM practices are there as there are many types of biological as well as cultural control methods of this insect. If none of the control methods seem to be working then chemical control is perhaps the last and considered to be most effective option for the control of insect pests of cotton. It is not a problem in BT Cotton.

    4. American Boll Worm

    Insect Pests of Cotton: American Bollworm
    Helicoverpa armigera is also called as the American bollworm and it is an important pest of chickpea and American Cotton. It is a polyphagous insect and is considered to damage a range of vegetable and other crops in Pakistan as well as other countries of South Asia. When it attacks the early stages it hollows the squares from inside and the damaged squares fall on the ground. It directly affects the cotton crop and results in lower yields. When the boll is mature it makes a prominent hole on the boll and results in the damage of the crop. The damage of American Bollworm is not observed in a uniform behavior rather it attacks in patches and affects the crop in patch. It shifts from one boll to another and damages dozens of bolls during life time. Biological control of this insect is the best option but in harsh conditions when biological control is not effective, chemical control serves as the only option for the control of American bollworm. It is not a problem in BT Cotton.

    3. Spotted Boll Worm

    Insect Pests of Cotton: Spotted Bollworm
    Earias insulana is also called as the spotted bollworm of cotton. It damages many parts of cotton crop and most of the times it is found boring in the reproductive as well as the vegetative parts of cotton. Despite of its lower attack it is a threat to the cotton in the early season. Premature opening of cotton boll is said to be the most important indication of the attack of spotted bollworm. It deteriorates the lint quality and results in lesser profits. It is not a problem in BT Cotton.

    2. Pink Boll Worm

    Insect Pests of Cotton: Pink Bollworm
    Pectinophora gossypiella is one of the most destructive pests of cotton crop in Pakistan. It attacks the flowering stage when the female lays eggs on the base of flower. The larvae make a very small hole and move inside the flower. The affected boll fails to open or it opens in a very awkward fashion indicating the attack of pink boll worm. It hibernates in between the seeds and Double Seeds are also the best indication of the damaged seeds. Farmers should avoid the use of Double Seeds that are stuck together by the silken threads of pupal stage of this pest. Cotton sticks serve as the best hiding place for this insect. It is not a problem in BT Cotton.

    1. Cotton Leaf Folder

    Cotton Insect Pests: Cotton Leaf Folder
    Sylepta derogata is also called as the cotton leaf folder. As the name is indicating the pest makes the leaves to roll. The older larvae roll the edges of leaves with the help of silken threads and feed on the leaf tissues after making roll. American cotton is worse affected. It is not a problem in BT Cotton. Like all the other pest of cotton the control of this pest should be planned after the determination of threshold levels. Biological control is considered to be optimum in case of the ideal conditions of temperature and humidity. During harsh conditions, chemical control is only option left. Attack of this pest is less on Native Cotton or Local Cotton.

    Army worm, aphid attack: experts warn cotton growers

    Friday, July 19, 2013
    Punjab Agriculture Department has warned the growers on Thursday that chances of attack of army worm and aphid on cotton crop have increased due to recent rains. Agricultural experts said that growers can save their crops from damages from these insects by developing their skills to recognise these and knowing the preventive and eradication steps. Army worm, aphid attack: experts warn cotton growersExperts also suggest that growers should spray recommended pesticides when attack of these pests reach economic threshold. A spokesman of the provincial agriculture department said that the experts have also recommended to make spray with intervals to eradicate weeds from the water courses.
    Source: Business Recorder

    Biotechnology: Cotton Production Set to Increase

    BY ORTON KIISHWEKO, 28 APRIL 2013
    RECENTLY, the Ministry of State in the Vice-President's Office (Environment) convened a meeting for stakeholders in the science community to deliberate on how crop genetic engineering can be used in the interest of agriculture and the local people in general.
    At the meeting some stakeholders had concerns on whether there is conclusive research findings that show genetically engineered crops have no harm on human beings.
    Biotechnology Cotton Production Set to Increase
    The same week, a renowned Harvard University scholar, Prof Calestous Juma visited East Africa and said biotechnology and genetic engineering have the potential to do for agriculture, what mobile technology has done for the communications sector in Africa.
    Prof Juma advocated for the adoption of Genetically Modified Organisms (GMOs), saying they would boost food and income security. He, however, cautioned that it would be detrimental to adopt GMOs without clear, flexible and supportive biotechnology regulations. Prof Juma has authored several books on Africa's development, including The New Harvest, which is arguably today's most authoritative scholarly work on agriculture in Africa.
    In his book, he argued that African agriculture is currently at a crossroads, at which persistent food shortages are compounded by threats from climate change. But, as the book argues, Africa faces three major opportunities that can transform its agriculture into a force for economic growth: advances in science and technology; the creation of regional markets and the emergence of a new crop of entrepreneurial leaders dedicated to the continent's economic improvement.
    Filled with case studies from within Africa and success stories from developing nations around the world, The New Harvest outlines the policies and institutional changes necessary to promote agricultural innovation across the African continent. Incorporating research from academia, government, civil society and private sector, the book suggests multiple ways that individual African countries can work with others at the regional level to develop local knowledge and resources, harness technological innovation, encourage entrepreneurship, increase agricultural output, create markets and improve infrastructure.
    He emphasised the role of technology in transforming livelihoods, insisting that if Africa didn't embrace GMOs in agriculture, the problems like climate change, pests and diseases that have dogged the sector over the years would devour production to shocking levels. He decried the phenomenon of resisting new technologies, saying it won't help Africa to develop. On the safety of GMOs, he compared the current debate to the rumours that were circulated during the early days of mobile technology that the phones would cause brain cancer.
    He said instead of focusing on rumours that discredit GMOs, it is prudent for governments to empower institutions to effectively check the safety standards of each product introduced on the market. He said biotechnology had caused a 24 per cent increase in cotton yield per acre and a 50 per cent growth in cotton profit among US smallholder farmers between 2006 and 2008. It raised consumption expenditure by 18% during the period.
    He cited another report which said GMO crops that are pest-resistant had suppressed pests even beyond gardens where they were planted to assist farmers who don't grow GMOs. "Biotechnology and in particular GMOs are not per se more risky than conventional plant breeding," he asserted, and explained that genetic engineering would make agriculture more attractive and reduce the number of youth running away from rural areas.
    The scholar's position brought into focus the importance of genetic engineering perhaps starting with non-food crops in Tanzania, including cotton. Locally, stakeholders have urged that the government should institute a policy that allows agricultural scientists to conduct research and trials on GMOs in different research centres. The Environmental Management Act does not allow the application of such research and that it should therefore be amended. For example, one of the crops whose future has elicited so much debate is cotton.
    Questions have been asked as to whether Bt Cotton can address the challenges in the cotton sector. The Tanzanian cotton sector has undergone dramatic changes since liberalisation in 1994. Stimulated by high producer prices, it has held either its position as either the most or second most important export crop in Tanzania in recent years. An estimated 40 per cent of the entire Tanzanian population is believed to derive their livelihood either directly or indirectly from cotton, grown by as many as half a million of mostly smallholder farmers.
    A recent World Bank publication remarks that the sector is unique in that it is marked with too much competition amongst buyers - resulting in higher producer prices yet lower qualities - compared to the other sub Saharan cotton economies. This increased competition- as a trade-off-also resulted in comparatively lower yields, as credit based input provisioning is challenging in an environment where an overcapacity in ginning fuels side-selling.
    The earlier South African case is illustrative in that the Tanzanian supply chain put into place via contract farming could serve a similar fate of struggling with recovering the debt and providing subsidized inputs, although measures are developed by the TCB to combat these issues. In addition to low yields obtained in a rain-fed environment, farmers in the sector struggle with lack of access to credit and extension service.
    Research in the cotton sector also has been limited with poor seed quality, although the new UK M08 variety - developed at the Ukiriguru Cotton Institute - is planned for release as early as 2013/14. Furthermore, the intense competition has resulted in a comparatively lower cotton quality, as buyers are more focused on securing their quantities for their orders. While the quality is improved by half the ginneries operating roller gins and the entire harvest being hand-picked, the sector continues to suffer from the collapse of the textile industry after liberalization.
    On average, only around 20 percent of the ginned cotton is consumed by domestic textile industries. The other 80 per cent are exported, thus revealing a potential source of domestic value addition as an estimated 90 per cent of the profits are obtained abroad (TCB 2010). These challenges were recognised by the Tanzanian Cotton Board as outlined in its Cotton Board Strategy of 2011-2013.
    Outside of its domestic domain, the cotton sector is plagued by a range of global structural issues. These include competition from synthetic fibres and a long term decline in terms-of-trade for agricultural commodities (that was reversed in the short-term during the commodity booms in the last few years).
    Courtesy: All Africa

    Pest of Cotton


    Important Pest of CottonNorth Carolina Cooperative Extension
    Extracted from INSECT and related PESTS of FIELD CROPS (AG-271)
    Dated 5/82
    Placed on the Web 10/94 by the Center for Integrated Pest Management, NCSU
    In 1980, cotton was planted on 25,506 hectares (63,000 acres) of North Carolina farm land. Cleveland County, the Scotland-Robeson counties area, and the Northampton-Halifax-Edgecombe counties area produce 90 percent of the cotton in North Carolina. Insects are an important factor in cotton production here but only the bollworm and the boll weevil are considered limiting. A pest management approach of varying degrees of sophistication has been applied for insect control in all cotton-producing areas of our state.

    Key to Pests of Cotton

    A. Insect and mite pests which pierce or rasp plant tissue to extract sap (Fig. A to D).


    1. Aphids
    2. - Usually feeding in colonies, these yellow, green or black, pear-shaped insects (Fig. A above) may be as long as 2 mm and may or may not have wings. Infested leaves curl and pucker; heavily infested seedlings become stunted and die. A black mold, which grows on the sticky, sugary "honeydew" that aphids excrete, is often evidence of aphid infestation.
      1. Cotton aphid
      2. - This aphid is usually yellow in the summer and pale or dark green in cooler seasons.
      3. Cowpea aphid
      4. - The adult of this species is black with white appendages. The nymph is pale gray with a powdery coating.
    3. Tarnished plant bug
    4. - Approximately 6.4 mm long, this oval-shaped, brown lygus bug (Fig. B above) has long legs, long antennae, and a white triangle between its "shoulders." It extracts sap from terminals, squares, flowers, and bolls, causing young fruiting forms to be shed. Infested flowers and bolls may open prematurely.
    5. Thrips
    6. - Several species of these yellow, orange, brown, or black rasping insects (Fig. C above) attack seedling cotton. Foliage infested by these tiny, fringed-wing insects becomes distorted and curls upward; terminal buds are sometimes killed.
    7. Twospotted spider mite
    8. - The almost microscopic, eight-legged, adult female mite is yellowish (Fig. D above) to dark green with 2 or 4 dark spots on its back. The immature mite may have 6 or 8 legs. Feeding on the underside of the leaf, this mite extracts sap, causing the upper leaf surface to have a whitish or bronze cast. Severe infestations can result in defoliation and loss of plant vigor. Silken webs are common on the underside of infested leaves, particularly along the large leaf veins.
    B. Caterpillars that chew or mine the foliage or sever seedling stems.
    1. Armyworms
    2. - These smooth-skinned, variously colored caterpillars have 5 pairs of prolegs, are occasionally problem foliage pests, and may be difficult to control chemically.
      1. Beet armyworm
      2. - This dark-headed (Fig. A above), green or black larva sometimes has 3 longitudinal, light stripes and usually attains a length of 25 to 30 mm. A small black spot occurs on each side of the second segment behind the head (Fig. B above). This larva normally skeletonizes foliage but at times feeds on squares, blooms, and bolls causing economic loss to cotton.
      3. Fall armyworm
      4. - Although this green, brown, or black caterpillar primarily attacks blooms, squares, and bolls, it also feeds on the foliage, occasionally tops plants, and bores into stems. This larva has 5 pairs of prolegs, reaches a maximum length of 40 mm, and often has distinct inverted "Y" on its head capsule (Fig. C above). It has a black, longitudinal stripe down each side of its body and a yellowish-gray stripe down its back.
      5. Yellowstriped armyworm
      6. - Reaching a length of up to 45 mm, the smooth-skinned, pale gray to jet black caterpillar has a yellowish-orange stripe along each side and a pair of black, triangular spots on the back of most segments (Fig. D above). Like the fall armyworm, this larva often has a pale but distinct inverted "Y" on its head capsule (Fig. E above). This insect rarely reaches damaging levels on cotton but is most injurious to seedlings.
    3. Cabbage looper
    4. - Reaching a length of about 40 mm, this green caterpillar has 3 pairs of prolegs and several longitudinal, white stripes. Its body tapers from rear to front. Its feeding leaves ragged holes in the foliage.
    5. Cutworms.
    6. These fat caterpillars reach a length of 40 or 45 mm and have 5 pairs of prolegs. They display a variety of feeding habits and curl up when disturbed. They sever seedling stems and occasionally feed on leaves.
      1. Black cutworm
      2. - The skin of this light gray to black cutworm is granulated, the granules resembling rounded, flattened pebbles (Fig. A). The caterpillar cuts seedlings off at the soil line during the night. It commonly pulls the cut stem of a seedling into the entrance of its burrow and feeds on it during the day.
      3. Granulate cutworm
      4. - This cutworm has a pale brown head, a dark brown band down its back and brown sides with faint stripes. The skin granules of this cutworm are like blunt cones as high as they are wide (Fig. B). The caterpillar also severs seedlings near the soil line at night.
      5. Variegated cutworm
      6. - Although primarily damaging to seedling stems, this species is a climbing cutworm and may feed on foliage. Its smooth-skinned body is pale gray to dark brown with a row of orange or yellow spots down the middle of its back. A black spot and a yellow spot occur on the eighth abdominal segment.
    C. Insects that feed in squares or bolls.
    1. Boll weevil larva
    2. - The white-bodied, brown-headed, legless grub (Fig. A), up to 13 mm long, feeds within squares or small bolls, destroying the contents.
    3. Boll Weevil adult
    4. - About 8.5 mm long, the reddish-brown or gray adult weevil (Fig. B) has a distinctive characteristic: a double-toothed spur on the inner surface of each front leg. The female punctures squares and young bolls to lay eggs. These nipple-like egg punctures are about 1 mm in diameter. Egg-punctured squares flare and fall to the ground where larval development is completed.
    5. Caterpillars
    6. - These moth larvae have 3 pairs of short legs near the head and 5 pairs of prolegs.
      1. Bollworm complex
      2. - When fully grown, these larvae are green, reddish, or brown with pale, longitudinal stripes and scattered, black spots. Early instars are cream colored or yellowish-green with few markings. Larval instars vary from 1.5 to 44 mm in length and have 5 pairs of prolegs. The contents of squares or bolls may be completely consumed by bollworms. Cotton lint development is reduced and rot organisms may gain entrance into the bolls that are only partially damaged.
      3. Fall armyworm
      4. -  This caterpillar may bore into stems and bolls like the bollworm, but typically enters the boll at the tip or at the base next to the stem.
      5. Yellowstriped armyworm
      6. - This larva occasionally bores into squares or bolls but is rarely an economic problem.
    Reference:
    For More Detail Visit excellent website
    http://ipm.ncsu.edu/AG271/cotton/cotton.html
    http://ipm.ncsu.edu/
     
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