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The dataset generation failed because of a cast error
Error code:   DatasetGenerationCastError
Exception:    DatasetGenerationCastError
Message:      An error occurred while generating the dataset

All the data files must have the same columns, but at some point there are 2 new columns ({'question', 'q_id'}) and 3 missing columns ({'c_id', 'Unnamed: 0', 'chunk'}).

This happened while the csv dataset builder was generating data using

hf://datasets/tensorboy/colbert_raw_data/queries.train.colbert.csv (at revision bca7b049ab4dbeb956183cbdb5d5ad71faa8bcaf)

Please either edit the data files to have matching columns, or separate them into different configurations (see docs at https://hf.co/docs/hub/datasets-manual-configuration#multiple-configurations)
Traceback:    Traceback (most recent call last):
                File "/src/services/worker/.venv/lib/python3.9/site-packages/datasets/builder.py", line 2011, in _prepare_split_single
                  writer.write_table(table)
                File "/src/services/worker/.venv/lib/python3.9/site-packages/datasets/arrow_writer.py", line 585, in write_table
                  pa_table = table_cast(pa_table, self._schema)
                File "/src/services/worker/.venv/lib/python3.9/site-packages/datasets/table.py", line 2302, in table_cast
                  return cast_table_to_schema(table, schema)
                File "/src/services/worker/.venv/lib/python3.9/site-packages/datasets/table.py", line 2256, in cast_table_to_schema
                  raise CastError(
              datasets.table.CastError: Couldn't cast
              q_id: int64
              question: string
              -- schema metadata --
              pandas: '{"index_columns": [{"kind": "range", "name": null, "start": 0, "' + 482
              to
              {'Unnamed: 0': Value(dtype='int64', id=None), 'c_id': Value(dtype='int64', id=None), 'chunk': Value(dtype='string', id=None)}
              because column names don't match
              
              During handling of the above exception, another exception occurred:
              
              Traceback (most recent call last):
                File "/src/services/worker/src/worker/job_runners/config/parquet_and_info.py", line 1324, in compute_config_parquet_and_info_response
                  parquet_operations = convert_to_parquet(builder)
                File "/src/services/worker/src/worker/job_runners/config/parquet_and_info.py", line 938, in convert_to_parquet
                  builder.download_and_prepare(
                File "/src/services/worker/.venv/lib/python3.9/site-packages/datasets/builder.py", line 1027, in download_and_prepare
                  self._download_and_prepare(
                File "/src/services/worker/.venv/lib/python3.9/site-packages/datasets/builder.py", line 1122, in _download_and_prepare
                  self._prepare_split(split_generator, **prepare_split_kwargs)
                File "/src/services/worker/.venv/lib/python3.9/site-packages/datasets/builder.py", line 1882, in _prepare_split
                  for job_id, done, content in self._prepare_split_single(
                File "/src/services/worker/.venv/lib/python3.9/site-packages/datasets/builder.py", line 2013, in _prepare_split_single
                  raise DatasetGenerationCastError.from_cast_error(
              datasets.exceptions.DatasetGenerationCastError: An error occurred while generating the dataset
              
              All the data files must have the same columns, but at some point there are 2 new columns ({'question', 'q_id'}) and 3 missing columns ({'c_id', 'Unnamed: 0', 'chunk'}).
              
              This happened while the csv dataset builder was generating data using
              
              hf://datasets/tensorboy/colbert_raw_data/queries.train.colbert.csv (at revision bca7b049ab4dbeb956183cbdb5d5ad71faa8bcaf)
              
              Please either edit the data files to have matching columns, or separate them into different configurations (see docs at https://hf.co/docs/hub/datasets-manual-configuration#multiple-configurations)

Need help to make the dataset viewer work? Make sure to review how to configure the dataset viewer, and open a discussion for direct support.

Unnamed: 0
int64
c_id
int64
chunk
string
0
8
'5. Mealy bug , Brevennia rehi , Pseudococcidae, Hemiptera Symptom of attack: The infestation starts in plants one or two month after transplanting. Stunted, circular patches may be seen in the fields. If such plants are pulled out and teased the insects can be seen at the base of the leaves and leaf sheaths. Nature of damage: Large number of these insects’ remains inside the leaf sheaths and suck up the plant sap. The affected tillers remain stunted with yellowish curled leaves. When the attack is severe, it inhibits panicle emergence. This type of disease is called as Soorai disease in Tamil Nadu. The damage occurs from September. In severe cases, yield may be reduced even upto 50%. Egg: The female lays numerous yellowish white eggs/ simply deposits nymphs in outer leaf sheaths. Nymph: The newly hatched nymphs crowded within the waxy threads for 6-10 h before they disperse to various parts of the same plant. The pale yellowish nymph is active and crawls about the plant for a while and settled itself on the plant/ stem and turns dark yellow after a day. Body gets covered with waxy material on second day. Adult: Nymphs and adults being wingless look alike. Females are reddish, oval, soft- bodied living in colonies inside the leaf sheath. Males are small, slender, pale-yellow, having single pair of wings and a style like process at the end of the abdomen but lack mouthparts. Males are seldom found in the colonies, so it reproduces parthenogenetically.'
1
10
'Egg: Eggs are cylindrical, greenish and laid in small groups of ten in two rows on the leaves. Nymph: Young nymph is brown with yellowish green abdomen and a few black spots. Adult: Adults are flat, 7-9 mm long, brownish black bugs with a prominent scutellum and pronotum having a spine on either side. It is active on the cloudy days and during night. Adults or late nymphal stage aestivate in cracks in bunds.'
2
174
'Family Eriophyidae 5. Aceria cajani : It is a vector of sterility mosaic of pigeonpea. 6. Aceria sorghii : Leaf crinkling, general chlorosis and choking of terminal leaves. Host plant is sorghum.'
3
175
'Chemical : Acaricides viz ., tetradifon, chlorbenzalite, dicofol/ kelthane, can be used to kill phytophagous mites in all stage of development. Biological : Some of the predatory mites and insects (coccinellids, Scolothrips indicus, Chrysopa ) produce effective control.'
4
56
'8. Ash weevil , Myllocerus spp., Curculionidae, Coleoptera 9. Pink stem borer , Sesamia inferens , Noctuidae, Lepidoptera 10. Semilooper , Antoba silicula , Noctuidae, Lepidoptera 11. Stink bug , Nezara viridula , Pentatomidae, Hemiptera 12. Stink bug , Dolycoris indicus , Pentatomidae, Hemiptera'
5
9
'6. Black bug, Scotinophara lurida, Podopidae, Hemiptera Symptom of attack: Presence of bugs at the base of the stem just above the water level. Plants stunted with reduced number of tillers; leaves turn reddish brown and dry . Nature of damage: The bugs remain and feed the plant sap on the base of the plants causing stunting of plants. Leaves turn reddish brown and grains do not develop. Bugs feed on the panicles in milky stage result in brown spots or empty grains in the panicles. Heavy bug infestation may cause death to the plants and whole field appears burned called bug burn similar to hopper burn.'
6
57
'ITALIAN MILLET 1. Stem borer, Anadastus parvulus , Languriidae, Coloeptera Symptom of damage: Scrapped leaves, plants wither and in severe cases. Nature of damage: Grubs bore into the stem and cause withering of plants. Adult beetle scrapes green matter on the leaves. Grub: Yellowish with chitinous spines on the surface of the anal segment. Adult: Small smooth beetle with red head and thorax and blue wings.'
7
176
'1. House Crow , Corvus splendens, Corvidae, Passeriformes It is grey and has black and grey wings with a black area on the throat and the forehead. It is omnivorous and feed on dead rats, carrion, kitchen scraps, locusts, termites, the eggs of other birds and the ripening grains of maize and fruits. Crow are particularly attracted to maize when it is exposed on the cob. They are often seen in flocks in maize and other fields. Management : Hanging a dead crow on the top of a pole can effectively be used as a scarecrow. Maize cobs can be protected by wrapping one or two of the nearby leaves around them. A large-wire gauze cage, 2x1x1 metres having on one side a converging entrance, can be used as a trap for crows if some attractive food is kept inside.'
8
177
'2. Common Myna , Acridotheres tristis, Saturnidae, Passeriformes It is a dark- brown bird, with a bright yellow bill, its legs and patches around the eyes. As it flies, large white patches become visible on the wings. It is omnivorous and feed on insects, earthworms, grasshoppers, fruits and kitchen scraps. They are seen in ripening maize and wheat fields feeding on the grains and their flocks are found alongside those of crows and parakeets. Management : Destroying the nests goes a long way in checking their multiplication.'
9
178
'3. House sparrow , Passer domesticus , Ploceidae, Passeriformes Female is ash to greyish brown above and fulvous ash-white below. The male is 15 cm long, darker above, with blackish streaks on the wings and a black patch on the throat and breast. It has prominent white cheeks. Feeds on grains of maize. Management : Spraying the wheat crop when ears are in the milky stage with Tetra Methyl Thiuram Disulphite (TMTD) 0.6% repels the sparrows and protects the crop.'
10
1,456
'LMP containing pectic acids are extracted with lower temperatures with less acidic solutions, but in presence of other chemical compounds. LMP are pectin derivatives which do not need sugar to gel. If used, they need to react with a calcium salt (dicalcium phosphate) which has to be added during jam making.'
11
1,457
'The fresh fruit tissue or separated parts, including the peel and core are heated in 95% alcohol or 0.05N HCl (pH 2.0) for 10-20 min at 70 o C to inactivate pectic enzymes. After the pretreatment, the materials is ground in an electric blender and placed in water. Versene or Na-EDTA is added at 2.0%. The pH is adjusted to 6.0. The mixture is heated for about an hour at 90-95 o C. The slurry formed is rapidly filtered and the pectin is precipitated from the solution using acidified alcohol. The precipitate is centrifuged and repeatedly washed with 70% alcohol. Acetone is used for dehydration and the pectin produced is vacuum-dried. It may also be dried in a hot-air oven at 50 o C for 4 h.'
12
1,853
'lue-green algae inoculum is sprinkled in the tray and water is let in. Standing water of 5 to 10 ithin a week, a thick algal scum is formed. At this stage, water drained out and soil is allowed to dry. The dried flakes of blue green algae are collected and'
13
58
'3. Black bug , Scotinophara lurida , Podopidae, Hemiptera 4. Earhead bug , Leptocorisa acuta , Alydidae, Hemiptera 5. Ash weevil , Myllocerus spp., Curculionidae, Coleoptera 6. Shoot bug , Peregrinus maidis , Delphacidae, Hemiptera'
14
22
'6. Yellow hairy caterpillar : Psalis pennatula : Lymantriidae: Lepidoptera Symptom of attack: Defoliated leaves. It is a minor pest. Egg: Eggs are laid in batches on the leaves covered with yellow hairs.'
15
23
'Larva: The caterpillar is yellow with red stripes and an orange head. Tufts of hairs are found all over, of which two in the anterior region and one in the posterior region are prominent. Pupa: Pupation is in a yellowish cocoon of hairs on the leaves. Adult: Moth is light yellow with bipectinate antenna.'
16
59
'1. Gram pod borer , Helicoverpa armigera , Noctuidae, Lepidoptera Symptom of damage: In the early stages, plants seen defoliated. Boreholes seen on the pods and affected pods have no seeds. Nature of damage: Young larva feeds on tender leaves, buds, flowers, and subsequently it bores into the pods and feeds on the seeds with its head and part of the body only thrust inside, the rest remaining outside. A single larva may destroy 30-40 pods before maturity. Egg: Spherical in shape with a flattened base, giving dome shaped appearance, surface is sculptured in the form of longitudinal ribs. Yellowish-white, glistening and change to dark brown, before hatching. Larva: Newly hatched caterpillar is sluggish and whitish-green in colour. Full-grown larva is 3.5-4.0 cm in length with pale-green body colour. However, the colour varies according to the food intake. Dorsal surface bears dark broken stripes. Head is reddish- brown. Larva is highly cannibalistic and readily eats one another. Pupa: It pupates in soil in earthen cell. Pupa is obtect type. Freshly formed pupa is greenish yellow in colour and darkened prior to emergence of moths. Adult: It is a medium-sized light brown coloured moth. On the forewings, there is speck that forms a V-shaped mark. Hind wings are dull grey coloured with a black border on the distal end. Female moth is bigger than male and presence of tuft of hairs on the tip of the abdomen.'
17
60
'2. Blue butterfly, Lampides boeticus , Lycaenidae, Lepidoptera Symptom of damage: Bore holes on buds, flowers, green pods and matured pods. Nature of damage: The larva bores into the buds, flowers and green pods just within couple of hours after hatching and feeds inside the developing grains. Egg: Eggs are laid on the buds, flowers, green pods and on shoot and leaves. Greenish white in colour, round in shape with a slight depression at the top. Larva: Newly hatched larva is yellowish green in colour with black head and a dark- brown patch on the prothorax and cylindrical body with scattered hair. Full-grown larva is yellowish green to yellowish red sometimes light purple in colour, ventral surface is light green. Whole larva is covered with small setae and marked with irregular black markings. It looks like a slug. Brownish mid-dorsal and yellowish lateral lines are well marked. Pupa: Pupa are green in colour later on it darkens and wings are also visible. Adult: It is medium sized butterfly. The colour of the wings is violet metallic blue to dusky blue. The tail of hind wings is black and tipped with white. The female is slightly bigger than the male. In males, the abdomen is slender and tapering, while in female it is long and broader at the tip.'
18
82
'1. Mustard aphid , Lipaphis erysimi , Aphididae, Hemiptera Nature of damage: Suck the sap from under surface of leaves. Nymph: Light yellowish green in colour and pear shaped. Adult: Darker than nymph.'
19
83
'2. Mustard sawfly,. Athalia lugens proxima , Tenthredinidae, Hymenoptera Nature of damage: Grub nibbles the margins of tender leaves and pod. Larva: Resembles lepidopterous caterpillar; oily black or green in colour. Adult: Adult with dark head and thorax and orange colour abdomen and translucent smoky wings with black veins.'
20
179
'Cultural : Deep sowing of seeds, covering the seeds with soil, pre-and post dating of sowing, growing of trap crops near the main one and use of plant varieties that are physically and gustatorily unattractive to birds.'
21
180
'Use of deterrents : Scare-crow (a human figure erected in the fields) or acetylene gun, a device by which loud bangs are produced by the action of water on calcium carbide; use of bioacoustics, in which bird’s stress or alarm signals are recorded and played in'
22
181
'Invertebrata Phylum : Mollusca Class : Gasteropoda Snails differ from slugs in having a spirally coiled shell over their body which in slugs is reduced and completely hidden under the mantle.'
23
182
'They do a lot of damage to vegetables, garden plants, the damage being more serious in the seedling stage. Giant African snails even damage plantation crops like arecanut, rubber buds and coffee.'
24
183
'Cultural : They can be handpicked and killed. Chemical : Metaldehyde (5%), copper sulphate solution (1%) and insecticides (aresenates, persistent organochlorines, etc.)'
25
223
'Leaf quality often determines when fruits and vegetables should be harvested. In root crops, the condition of the leaves can likewise indicate the condition of the crop below ground. For example, if potatoes are to be stored, then the optimum harvest time is soon after the leaves and stems have died. If harvested earlier, the skins will be less resistant to harvesting and handling damage and more prone to storage diseases.'
26
1,458
'A pectin solution of maximum strength can be obtained with about 30 min of boiling. When this period is divided into two, each of 15 min period of extraction, maximum amount of pectin can be extracted. Other jellying agents include agar, arrow root, tapioca flour or cassava starch.'
27
1,459
'Tea is one of the most popular beverages in the world. It also provides valuable source of income to many tea producer countries. It is a capital earning industry. To promote its development, the Govt. of India has set up'
28
1,460
'Tea is a perennial plant having a lifespan extending 100 years. The popularity of tea is due to: • Its sensory properties • Relatively low retail price • Apparent health benefits'
29
2,289
'Streptomycin sulpahte bottle @ Rs 7 / bottle Rs 28/= 1 Formalin 40 Y @ 300 ml / month Rs 60/= For I yr Rs 720/= Blotting paper sheet 1 yr 50 sheets x 2 Rs 100/='
30
27
'producing only partially filled/ half filled grains. Small puncture appear in the middle of the flag leaf and its margin get discolored. Egg: White, cigar shaped egg laid singly on either side of the leaves. Grub: Newly hatched larva is transparent to very light cream in colour but later become yellow. The larvae move down the leaf into the whorl on a film of dew and feed within developing whorls. The larvae mostly remain outside the leaves and feed on the mesophyll tissue of the foliage. When leaves emerge from the whorl damage can be seen as pinholes in the leaves and white and yellowish lesions on the leaf edge. Pupa: Pupation takes place in between the leaf sheath where the pupa is loosely attached to the stem. The puparium is light to dark brown ovoid and sub-cylindrical in shape. Adult: Adult dark grey flies, 1.8-2.3 mm in size.'
31
26
'9. Whorl maggot : Hydrellia sasakii : Ephydridae: Diptera Symptoms of attack: Presence of feeding lesions in the lines and the infested plants become stunted. Nature of damage: The maggots are found to feed on the unopened leaves and to nibble the inner margins of the leaves, which showed conspicuous feeding lesions in the lines. Damaged leaves became distorted and broke-off in the wind. Infested plants are stunted. It cause damage to the boot leaf and developing panicles, which resulted in'
32
28
'1. Shoot fly : Atherigona varia soccata : Anthomyiidae: Diptera. Symptom of attack: Dead heats or drying of central shoots or production of profuse side tillers in main plants. Nature of damage: The maggots bore into the shoot of young plants, a week after germination to about one month and as a result the central shoot dries up. If the plants are attacked at the initial stages the mother plant may produce profuse side tillers, but the tillers also may be attacked. The infestation often goes as high as 60%. The high yielding hybrid varieties are severely attacked. In South India, crop is damaged during October to December as also in summer. Egg: Whitish eggs are laid singly on the under surface of the leaves which are about one week old. Maggot: The maggots are yellow in colour migrate to the dorsal surface of the leaf, enter the space between the leaf sheath and the axis and make a clear cut through the tightly rolled sheaths and damages growing point. The growing points of the plant die and decay on which the maggots feed. Pupa: Pupation takes place inside the stem itself. Adult: The adult is a small dark fly. Female fly has whitish grey head and thorax, while the abdomen is yellowish with paired brown patches. Male is darker in colour.'
33
34
'III. SAP FEEDERS 8. Shoot bug : Peregrinus maidis : Delphacidae: Hemiptera Symptom of attack: The leaves turn yellow due to sucking; plants become weak and the yield goes down. The mid rib of the leaves become red due to egg laying and may dry up subsequently. Nature of damage: Both adults and nymphs suck the plant sap from the leaves and cause the shoot to dry. They feed gregariously within the leaf sheaths. It is not a serious pest, but sometimes causes appreciable damage. Life stages: It is a small active, grayish brown bug. Colonies of this bug (both adults and nymphs) live within the whorl of the central leaf or in the root region. This pest is very common in Coimbatore during summer. The large black ant attends these insects.'
34
35
'9. Plant lice : Rhopalosiphum maidis, Longuinguis sacchari : Aphididae: Hemiptera Nature of damage: Nymphs and adults suck plant sap from the leaf, leaf sheath and inflorescence. They occur in cluster and may cause severe damage to inflorescence by hampering pollination. The aphid colony secretes honeydew in plenty. Life stages: The former one is yellow with dark green legs and lives inside the central leaf. The latter is creamy and lives on the under the surface of lower leaves. These are not serious pests. Reproduction parthenogenetic. Cloudy and humid weather favours reproduction.'
35
1,461
'The history of tea production in India spans more than 160 years. In 1838, the first consignment of tea from Assam was shipped to England. The word ‘Chai’ is derived from a Cantonese word ‘Chah’ . Plantations in Darjeeling, Tarai and Dooars regions of northern Bengal and Nilgiris and other regions of South India.'
36
2
'2. Green leafhopper, Nephotettix virescens , Cicadellidae, Hemiptera Symptoms of attack: Affected plants become pale yellow in colour and get stunted in growth. If the plants are tapped large number of leafhoppers may be seen jumping to water. Nature of damage: Both nymphs and adults suck the plant sap from the leaf and leaf sheath. (It is a phloem feeder. Amino acid content is high in phloem sap than xylem. The xylem and phloem vessels are plugged with their stylet sheath that causes disruption in the transport of food substances in the vessels.) Mild infestation reduces the vigour of the plant and the number of reproductive tillers. Heavy infestation causes withering and complete drying of the'
37
1
'1. Thrips, Stenchaetothrips biformis, Thripidae, Thysanoptera Symptom of attack: Affected nurseries present a pale yellow colour with brown tips . On passing the wet palm over the top of the seedlings a large number of black adults and yellowish nymphs may be seen striking to the palm. The infestation invariably disappears after sharp showers. Nature of damage: Both the adults and nymphs lacerate the tender leaves and suck up the plant sap. As a result fine yellowish lines or silvery streaks are seen on the leaves. Later, the leaves curl longitudinally and begin to dry from the tip downwards. In severe cases, the entire nursery may dry up and fail to produce seedling. Sometimes transplanted crop is also affected in the early stages. Life stages Egg: Eggs laid singly in the tissues of the tender leaves on the sides facing the stem. Eggs are hyaline and turn pale yellow as they mature. Nymph: Newly hatched nymphs are transparent but turn yellowish white after the first moult and possess darker legs, head and antennae. Pupa: Pupation takes place inside the rolled leaves and appendages and wings are clearly visible. Adult: Adult is 1 mm long, dark brown to black in colour with fringed wings. Male is smaller, more slender than female. It reproduces parthenogenetically since males are seldom seen in the population.'
38
3
'ovipositional punctures. Nymphs and adults exude sticky, whitish honeydew, which attracts sooty mould (that reduces the photosynthetic rate) . It also transmits plant diseases such as dwarf, transitory yellowing, yellow dwarf and rice tungro virus (Tungro is transmitted during short feeding period). Life stages Egg: Greenish transparent eggs are deposited in the midrib of leaf blade or sheath of rice or green grass. They are laid in batches of 10 to 15 arranged in a single row. Nymph: The nymphs are soft bodied, yellow white in colour. Gradually the colour changes to green.'
39
4
'Adult: Adults are 3-5 mm long, bright green with variable black markings, wedge shaped with a characteristic diagonal movement. Male insect has a black spot in middle of the forewings that is absent in females. The insect is active during July to September.'
40
5
'3. Brown planthopper/ Fulgorid, Nilaparvata lugens, Delphacidae, Hemiptera Symptom of attack: Symptoms will not be visible from outside in the early stages, but if we enter the field and tap the plants large number of this insect can be seen. They are visible only when the damage has been severe, the plants present a burnt up appearance, hopper burn, in circular patches. Nature of damage: Both the nymphs and adults remain at the ground level and suck the plant sap. It is a typical vascular feeder primarily sucking phloem sap leading to hopper burn . At early infestation, circular yellow patches appear which soon turn brownish due to the drying up of the plants. The patches of infestation then may spread out and cover the entire field. The grain setting is also affected to a great extent. During sustained feeding, it excretes a large amount of honeydew . It also acts as vector of the virus diseases like grassy stunt, wilted stunt and ragged stunt. (Transmission of persistent ragged stunt and grassy stunt virus require more time. Sheath blight and stem rot incidence was high in BPH infested plants.) Life stages Egg: Eggs are laid in a group of 2 to 12 in leaf sheath (near the plant base or in the ventral midribs of leaf blades) . White, transparent, slender cylindrical and curved eggs are thrust in straight-line in two rows . (They are covered with a dome-shaped egg plug secreted by the female. Only the tips protrude from the plant surface.) Nymph: Freshly hatched nymph is cottony white, 0.6 mm long and it turns purple- brown, 3.0 mm long in the fifth instar. Adult: Adult hopper is 4.5-5.0 mm long and has a yellowish brown to dark brown body. The wings are sub hyaline with a dull yellowish tint. It has two characteristic wing morphs: macropterous (long winged ) and brachypterous (short winged). (Wing morphism is influenced by various factors viz., crowding during the nymphal stage and reduction in the quality and quantity of food, short day length and low temperature, which favour macroptery)'
41
224
'As part of the natural development of a fruit an abscission layer is formed in the pedicel.'
42
225
'4 A fruit may change in texture during maturation, especially during ripening when it may become rapidly softer. Excessive loss of moisture may also affect the texture of crops. These textural changes are detected by touch, and the harvester may simply be able to gently squeeze the fruit and judge whether the crop can be harvested.'
43
6
'Symptom of attack: Heavy infestation cause outer leaves of a hill to show burn symptoms. Damage in the form of hopperburn appears uniformly in a rice field, whereas it appears as circular patches in the case of BPH. Nature of damage: WBPH is more abundant during the early stage of the growth of rice crop, especially in nurseries. (It attacks less than four-month old plants in fields with standing water and shows a marked increase with the age of the crop. Rice is more sensitive to attack at the tillering phase than at the boot and heading stages. ) Damage is caused through feeding and oviposition. Gravid females cause ovipositional punctures in leaf sheaths. Both nymphs and adults suck phloem sap causing reduced vigour, stunting, yellowing of leaves and delayed tillering and grain formation . (Rice crop fails to produce complete grains [seedless glumes] and this condition is known as red disease in Malaysia.) Feeding puncture and lacerations caused by ovipositor predispose the plants to pathogenic organisms and'
44
7
'honeydew excretion encourages the growth of sooty mould . It is not a vector of any viral disease. Egg: Cylindrical eggs are laid in groups when the rice plant is small but in the upper part of the rice plant when the plant is large. (They are laid with the micropylar end protruding from the tissue, the operculum is long and narrow. The eggs in a group are not sealed together by the material secreted by female.) Nymph: White to a strongly mottled dark grey or black and white in colour and 0.6 mm size when young. Fifth instar nymph with a narrow head and white or creamy white body. Dorsal surface of the thorax and abdomen marked with various amounts of grey and white markings. Adult: The adult hopper is 3.5-4.0 mm long. The forewings are uniformly hyaline with dark veins. There is a prominent white band between the junctures of the wings. Macropterous males and females and brachypterous females are commonly found in the field.'
45
184
'1. Rice weevil, Sitophilus oryzae, S. zeamais, S. granarius, Curculionidae, Coleoptera Host range: Wheat, rice, maize, jowar, paddy. Life history: 150-250 E 4-5 d L 20 d A 3-6 d P Symptom of damage: Presence of irregular holes of 1.5 m diameter on grains of rice, sorghum, wheat, barley, maize before harvest and in store. Nature of damage: Both grub and adults cause the damage. Grains are hollowed out; kernels are reduced to mere powder. S. oryzae and S. zeamais starts its attack in field itself. Adults cut circular holes. Heating takes place during heavy infestation, which is known as ‘dry heating’. Egg: Translucent white, plugs the egg hole with gelatinous secretion, laid singly. Grub : White with yellowish brown head, apodous, fleshy, curved, remains within the grain Pupa: Pupates inside the grain. Adult: Small, reddish brown to chocolate coloured weevils has characteristic snout, elbowed antennae, slightly clubbed. Hindwings present except in S. granarius. S. zeamais is the largest amongst the three species.'
46
226
'Physical and chemical treatment to increase the shelf life conditions for'
47
11
'7. Earhead bug/ Gundhi bug, Leptocorisa acuta , Alydidae, Hemiptera Symptom of attack: Leaves turn yellow and later rusted from tip downwards. Appearance of numerous brownish spots at the feeding sites / shrivelling of grains. In the case of heavy infestation, the whole earhead may become devoid of mature grains. Its presence in the field is made out by its strong smell. Nature of damage: Both adults and nymphs do the damage. The nymphs start feeding 3 to 4 hours after hatching. They feed on the leaf sap near the tip/ on milky sap in developing spikelets at milky stage. Sucking of the milky sap causes ill-filled/ partial filled and chaffy grains . Serious infestation can reduce the yield by 50%. The straw gives off-flavour that is unattractive to cattle. Egg: Eggs are circular, brownish seed like, 2 mm long, laid in clusters in two rows along the midrib on the upper surface of the leaf-blade. Nymph: First instar is small, 2 mm long, pale green in colour, which grows to deepen green through different instars. Adult: Adults are greenish yellow, long and slender, above ½ inch in length with a characteristic buggy odour.'
48
12
'8. Earhead stink bug/ Shield bug/Red spotted bug, Menida histrio, Pentatomidae, Hemiptera Symptom of attack: Small dot like discoloration on the grains. Nature of damage: Both adult and nymph suck the sap/ milk of developing rice grain and cause pecky rice . (Grain discoloration is caused by subsequent infections of pathogenic fungi or bacteria on the sucking injuries and such grains are called as pecky rice). Sucking of this pentatomid bug causes comparatively small dot like discolorations on the grain than by L. acuta. Egg: Eggs are laid in masses of 2-6 on leaves. Nymph: Nymphs are dark brown. Adult: It is a small brown bug with red and yellow spots.'
49
13
'Minor pests 1. White leafhopper, Cofana spectra, Cicadellidae, Hemiptera 2. Nama vandu/ Stripped bug, Tetroda histeroides, Pentatomidae, Hemiptera 3. Blue leafhopper, Empoascanara spp., Cicadellidae, Hemiptera 4. Zigzag leafhopper, Recilia dorsalis , Cicadellidae, Hemiptera'
50
14
'1. Paddy stem borer , Scirpophaga incertulas, Pyraustidae, Lepidoptera Symptoms of attack: A number of stem borer moths seen dead and floating on the water in the fields. In the vegetative stage, dead hearts seen in the affected tillers and in the reproductive stage, whiteear may be seen. Nature of damage: The insect may start attacking the plants in the nursery especially long duration varieties. The incidence is mild in the season June to September, but later on gets intensified from October to January and February. The caterpillar enters the stem and feeds on the growing shoot. As a result the central shoot dries up and produces the characteristic dead heart . The tillers may get affected at different stages. When they are affected at the time of flowering the earheads become chaffy and are known as white ear . Egg: Eggs are creamy white, flattened, oval and scale like and laid in mass. Each egg mass consists of 15-80 eggs and covered with buff coloured hairs. Before hatching, the eggs darken to a purplish tinge. They are laid mostly near the tip of the leaves. Larva: The hatched larvae move downward and wander about on the plant for 1 or 2 hours. They may hang down by a sliver thread and get to other plants with the help of the wind. They can also swim over the water and reach other tillers. They enter the leaf sheath and feed upon the green tissues of the stem for 2-3 days. Then they bore into the stem near the node. Deposition of silica in the epidermal layer of the stem and leaf sheath acts as an obstacle to the first instar larvae to chew up a hole. Generally only one caterpillar is seen inside a tiller. It may come out and attack fresh tiller. The full-grown caterpillar measures about 20 mm, white or yellowish white in colour with a conspicuous prothoracic shield. Pupa: Pupation takes place inside the rice stem, straw or stubble. Before pupation it make a exit hole in the internode and covers it will a thin web for the adult to come out later. The anterior extremity of the cocoon is tubular and attached to the exit hole and to make the cocoon waterproof the larva webs two horizontal septa in this tubular area. Adult: They exhibit remarkable sexual dimorphism. The female moth is bright yellowish brown with a black spot at the centre of the forewing and a tuft of yellow hairs at the anal region. The male is small in size and brownish.'
51
1,462
'Centre of origin – Southeast China Later it spread to Southern portion of China, parts of India, Myanmar, Thailand, Laos and Vietnam Early part of 19 th Century – An unsuccessful attempt was made to establish Chinese tea in India. Only when the native „wild‟ tea plants found in Assam were used, the tea production in India became successful.'
52
39
'Red hairy caterpillar: Amsacta albistriga : Arctiidae: Lepidoptera Angoumois grain moth: Sitotroga cerallela : Gelechiidae: Lepidoptera Cryptoblabes sp.: Pyralidae: Lepidoptera Flower webber: Eublemma silicula : Noctuidae: Lepidoptera Dolicoris indicus : Nezara viridula : Pentatomidae: Hemiptera These pests are found on the earheads in the milky stage. The injury is only very little.'
53
150
'1. Hairy caterpillar , Utethesia pulchella, Arctiidae, Lepidoptera Symptom of damage: Defoliation of the plant. Nature of damage: Larva feeds on leaves and also cause severe damage by feeding on the contents of developing pods.'
54
15
'2. Paddy gall midge, Orseolia oryzae , Cecidomyiidae, Diptera Symptom of attack: The central shoot instead of producing leaf produces a long tubular structure. When the gall elongates as an external symptom of damage, the insect will be in pupal stage and ready for emergence. Nature of damage: The maggot bores into the growing point of the tiller and causes abnormal growth of the leaf sheath, which becomes whitish tubular and ends bluntly. It may be pale green, pink or purplish. Further growth of tiller is arrested. This is called onion shoot , silver shoot or anaikomban . The feeding by the maggot and the larval secretion, which contains an active substance called cecidogen, is responsible for cell'
55
16
'proliferation of the meristematic cells and gall formation. It is a pest in irrigated and wet season crop. Tillers in 35 to 53 days old crops are preferred. Egg: The fly lays elongate, cylindrical, shinning white or red or pinkish eggs singly or in clusters (2-6) at the base of the leaves. Maggot: Maggot is 1 mm long after hatching with pointed anterior end. It creeps down the sheath and enters the growing bud. An oval chamber is formed round the site of feeding. Pupa: At the time of emergence the pupa wriggles up the tube with the help of antennal horn to the tip of the silver shoot and projects half way out. Adult: The adult fly is yellowish brown and mosquito like. The male is ash grey in colour. Adults feed on dewdrops.'
56
17
'1. Swarming caterpillar : Spodoptera mauritia : Noctuidae: Lepidoptera Symptom of attack: Nurseries found completely eaten away by the caterpillars’ overnight. Nature of damage: Caterpillars march in large numbers in the evening hours and feed on the leaves of paddy seedlings till the morning and hide during daytime. They feed gregariously and after feeding the plants in one field march onto the next field. Under severe infestation crop gives the appearance of grazed plants . Attacked plants are reduced to stumps. Nurseries situated in ill-drained marshy areas attacked are earlier than dry ground. Damage is severe during July to September. Egg: Eggs are spherical and creamy in colour, which are laid in a group covered over with grey hairs. Larva: The caterpillars are light green with yellowish white lateral and dorsal stripes in the early stages and later become dark brown or grayish green in colour with a crescent (semi-circular) shaped black spot on the side of each segment. Pupa: They pupate inside the soil in earthen cocoons. Pupa is dark brown and measures 16-17 mm long. Adult: The adult moth is medium sized, stout built dark brown with a conspicuous triangular black spot on the forewings. Hind wings are brownish white with thin black margins.'
57
32
'6. Leaf roller : Marasmia trapezalis : Pyralidae: Lepidoptera Symptom of attack: Rolled up leaves in which the larvae are found feeding and longitudinal patches on leaves whose tips dry are the clear symptoms. Nature of damage: The leaf roller becomes quite serious on young crops and feeds on the leaf epidermis. It causes longitudinal patches on the leaves and the tips of the leaves dry up. It is only a minor pest and rarely becomes serious. The varieties with broad leaves are attacked more severely. Egg: Eggs are laid on young leaves. Larva: A caterpillar is greenish yellow and is provided with setae over its body. Head and thoracic shield are brownish in colour. When full grown the caterpillar measures about 20 mm. Pupa: Pupation takes place within the rolled leaf. Adult: Adults are grayish with shining coloured patterns. Anal margins are darker in colour.'
58
33
'7. Flea beetle : Cryptocephalus schestedti : Chrysomelidae: Coleoptera Monolepta signata : Chrysomelidae: Coleoptera Symptom of attack: Shot holes. Nature of damage: The pest occurs in small number is feeding on the leaves. It nibbles small holes on the leaves. Life stages: C. schestedti : This is an yellow beetle with long black streak. M. signata : Adult is a black beetle with four yellow spots.'
59
185
'2. Sweet potato weevil, Cylas formicarius , Apionidae, Coleoptera Host range: Sweet potato. Life history: 200 E 3-5 d G Total life cycle : 1-1 ½ mon A 7-10 d P Symptom of damage: Grubs and adults bore into the tubers and make them unfit for consumption. Nature of damage: It is an important pest both in the field and in storage. Grubs bore into the tubers and make them unfit for consumption. They also attack the vines. Adult weevils feed on leaves, vines and tubers. Egg: Eggs are laid singly in small cavities on vines and tubers. Grub: Whitish grub is apodous and has a brown head. Pupa: It pupates inside the vine or tuber. Adult: Slender, ant-like with a long snout, shiny black with reddish brown thorax and legs.'
60
18
'2. Rice case worm : Nymphula depunctalis : Pyraustidae: Lepidoptera Symptom of attack: Plants stunted, caterpillars hanging on the leaf edges in a tubular case . Nature of damage: The caterpillar cuts a piece of leaf, rolls it longitudinally into a tubular structure and remains inside. It feeds by scraping the green tissue of the leaf. The cases often float in the water. Its damage can be distinguished from damage by other pests in two ways, firstly the ladder like appearance of the removed leaf tissue resulting from the back and forth motion of the head during feeding and secondly the damage pattern is not uniform through out the field because the floating cases are often carried in the run off water to low lying fields where the damage is more concentrated. Egg: Eggs are light yellow, disc like, smooth and irregular in shape. They are laid on the under side of the leaves floating on the water. Larva: They hatch into green caterpillars with orange brownish head. Each caterpillar lives inside a tubular case and hang down the leaves. The tubular cases are open at one end. The inside of the case is lined with silk to hold a thin film of water, which is essential for respiration and preventing desiccation of the larvae. The cases are replaced with each moult. It moves up and down with the protruded legs and scrapes the green matter. It drops in the water when disturbed. It is semi aquatic and can breathe by filamental gills at the sides. Full-grown caterpillars measure upto 15 mm length. Pupa: It pupates inside the leaf case. Fresh pupae are milky white, which gradually turn to light yellow.'
61
19
'3. Rice skipper : Pelopidas mathias : Hesperidae: Lepidoptera Symptom of attack: Leaves folded longitudinally and scrapped patches in such places. Nature of damage: The caterpillar folds the leaves and feeds from inside. It feeds on the parenchyma and leaf gets reduced to skeleton. Occurs in the nursery and planted crop. Not a serious pest. Egg: Eggs are laid on the leaves. Larva: The caterpillar is elongate, yellowish green with four white dorsal stripes, smooth and with a constructed neck and red ‘V’ mark on the head, which is distinct. Pupa: Pale green pupa has white longitudinal lines on it and is attached to the leaf blade by a silk girdle. Adult: The adult is a dark brown skipper butterfly with two white spots on the wings.'
62
20
'4. Leaf folder/ roller : Cnaphalocrocis medinalis : Pyralidae: Lepidoptera Symptom of attack: Leaves folded longitudinally or transversely with silk and scrapped patches in such places. Nature of damage: Larvae remain inside the fold and scrapping off green portion of the leaves leaving white patches. Egg: Flat oval yellowish eggs laid singly or in pairs on the undersurface of tender leaves. Larva: Larva is yellowish green in colour and translucent about 16-20 mm long. Pupa: It pupates inside the fold. Adult: Adult is small yellow coloured moth with dark wavy lines on both pairs of wings.'
63
21
'5. Rice horned caterpillar : Melanitis ismene : Nymphalidae: Lepidoptera Symptom of attack: Defoliated leaves. It is a minor pest. Nature of damage: The larva feed on the paddy leaves at night, remaining inactive during daytime. Egg: Eggs are white, round laid singly on the paddy leaves. Larva: Larva is green in colour with roughened skin, flattened dorsally and has a dark brown head with a pair of red horn like processes and two yellow processes in the anal end. It feeds on the leaves. Pupa: Dark green chrysalis hangs from the leaf and is attached to the leaf blade by its anal extremity. Adult: The butterfly is dark brown with large wings having a few black and yellow eye- like markings one on each of the forewings and six ocellar spots on hindwings.'
64
186
'3. Lesser grain borer/Hooded grain borer/paddy borer beetle, Rhyzopertha dominica , Bostrychidae, Coleoptera Host range: Paddy, rice, wheat, maize. It is able to attack paddy more easily than S. oryzae. Life history: 550 E 4-6 d G 4'
65
227
'Fruits and vegetables are processed by various methods like low temperature, thermal treatment, concentration, freezing and irradiation. But prior to subjecting fruits and vegetables to such treatments, all fruits and vegetables undergo some preliminary operations. Each processing method is based on certain principles and each has its own advantages and disadvantages.'
66
24
'7. Grass hoppers : Hieroglyphus banian (Large grasshopper) Oxya nitidula (Small grasshopper) : Acrididae: Orthoptera Symptom of attack: The nymphs and adults nibble leaves and also earheads in the early stages. Nature of damage: Both the adults and nymphs feed on the leaf and in severe cases the entire leaf may be eaten away. It is capable of causing severe damage. In the earhead stage the adults nibble at the tender florets or grain or into the base of the stalks causing white ears. Life stages H. banian has only one brood in a year. O . nitidula breeds throughout the year. Egg: It lays eggs in the wet sandy soil during October to November at a depth of about 2”especially in the side of bunds. The eggs are laid in batches of 30-40, hatch only in June to July on receipt of the monsoon rains. Eggs are yellowish and covered with gummy substrate that hardens into a waterproof coating. Nymphs: The nymphs feed on the grasses or paddy Adult: They grow into adults by August to September. H. banian measures about 1½ inches long. There are three transverse dark lines on the prothorax, which is helpful for identifying the pest. O. nitudula is about one inch long and has a longitudinal brown streak on either side of the thorax.'
67
25
'8. Spiny beetle/ Rice hispa : Dicladispa armigera : Chrysomelidae: Coleoptera Symptom of attack: The mining of the grubs will be clearly seen on the leaves. White parallel line will be clear on the leaves. Nature of damage: The grub mines into the leaf blade and feed on the green tissue between the veins. Adults also feed in the green tissue; they scrape the green matter of the tender leaves. Generally the plants are affected in the young stage. Egg: Eggs are laid inside minute slits on the tender leaves generally toward the tip. Grub: The grub is whitish yellow and flattened. It feeds inside the leaf tissue by mining. It pupates inside. Adult: The adult beetle is somewhat square shaped about 1/6 to 1/8” in length and width. Dark blue or blackish in colour with spines all over the body.'
68
47
'9. Whitegrub, Holotrichia consanguinea , Melolonthidae, Coleoptera Symptom of damage: Death of grown up plants. Leaves and tender shoots nibbled. Nature of damage: Grub feed on the root and rootlets, results in the death of the plants. Adults nibble on the leaves and tender shoots. They can move under soil, thus can migrate from one plant to another.'
69
48
'10. Root aphid , Tetraneura nigriabdominalis , Aphididae, Hemiptera Symptom of damage: Wilting and drying of plants in patches. Presence of black ants, Camponotus compressus , around the base of the plants. Nature of damage: Nymph and adult attack underground parts of the plants, they suck sap from roots. Plants become weak and may wilt. Nymph and Adult: Pinkish globular aphids.'
70
49
'3. Cutworm, Agrotis ipsilon , Noctuidae, Lepidoptera Symptom of damage: Cutting of tender stem and defoliation. Nature of damage: Larva defoliates the crop. Larva: Greasy to touch; coil up at the slightest touch. Blackish brown with red head, greyish green laterally with dark stripes. Adult: Stout moth with brownish forewings with wavy lines and spots; hindwings hyaline.'
71
84
'6. Flea beetle , Phyllotreta cruciferae , Alticidae, Coleoptera 7. Diamond back moth , Plutella xylostella , Plutellidae, Lepidoptera Lecture No. 11. PESTS OF OILSEEDS - GROUNDNUT'
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'Symptom of damage: Branches may droop and the plants show wilting and may die when the grubs reach the root. Nature of damage: Grubs tunnel the stem just below the soil surface and main roots, tunnel containing elongate flat-headed grubs. Life stages Egg: Small flat oval eggs laid on the main stem of the plants. Grub: Slender pale whitish with flattened anterior portion, called ‘flat-headed grubs’. Pupa: Pupation occurs inside burrows (tunnels) from which the adult beetles emerge by cutting their way out. Adult: Dark brown, shiny beetle, jewel like and small (1 cm) beetle.'
73
29
'2. Stem borer : Chilo partellus : Crambidae: Lepidoptera Symptoms of attack: Presence of circular holes on the unfolded leaves and dead hearts in the early stages are the main symptoms. The boreholes may be visible in contrast to the dead heart caused by the stem borer. When grown up plants are attacked the symptoms will not be quite visible. Nature of damage: The caterpillar bores into the stem and feeds on the central shoot. There may be more than one caterpillar in a single plant. In early stages, the caterpillars make circular holes on unfolded leaves and later central shoot dries up producing dead heart. Later it acts as an internode borer and is found till the time of harvest. Young cobs may also be attacked. Yield is affected much and the quality of the fodder is also reduced. The damage caused to the crop by this pest was estimated to range between 70 – 80%. Egg: Eggs are yellowish in colour, flat and oval, laid on the underside of the leaves, near the midrib. Larva: The larva is pale white with black dots and brown head. The newly hatched caterpillars migrate to the top of the plant and enter the stem or it mines in the midrib or bores into the stem near the node and feeds upwards. The larvae remain dormant in winter and hibernate. A caterpillar is dirty white with a brown head and thorax. There are four longitudinal stripes on its dorsal surface. Pupa: Pupation takes place inside the stem. Adult: Moth is medium sized and straw coloured. Male has pale brown forewings provided with dark brown scales forming a dark area along the coastal margin. Hind'
74
30
'3. Pink Stem borer : Sesamia inferens : Noctuidae: Lepidoptera Symptom of damage: Presence of dead heart. Nature of damage: The young larvae after hatching, congregate inside the leaf whorls and feed on folded central leaves causing typical ‘pin hole’ symptoms. Severe feeding results in killing of the central shoot and consequent dead heart formation. Usually the second instar larvae migrate to neighbouring plants by coming out from the whorls and suspending themselves from the plants by silken threads, these are then easily blown off by wind to other plants. These larvae penetrate in the stem and cause tunneling resulting in stunting, infested plants become weak and bear very small earheads. The weakened stems, especially of tall local varieties, break easily during heavy rains or with high velocity winds. Egg: Creamy white spherical eggs are laid in batches in between leaf sheaths and stem of a plant. Larva: The larvae penetrate the stems directly and may kill the young plants. The fully developed caterpillar is cylindrical, pinkish dorsally and whitish ventrally. Larvae can migrate from plant to plant. Pupa: Pupation occurs inside the stem, pupae are robust and light brown in colour. Adult: Adults are stout, straw coloured and are nocturnal in habit.'
75
31
'II. LEAF FEEDERS 5. Slug caterpillar : Thosea apierens : Cochlididae: Lepidoptera Symptom of attack: Defoliation. Nature of damage: They feed on the leaves and defoliate. Apart from this they cause lot of irritation on the people who work in the field. Harvest is made difficult and it is reported the even cattle do not relish the fodder. Life stages: Slug is found to appear in a severe form in Coimbatore.'
76
55
'4. Root grub , Arthrodeis sp., Tenebrionidae, Coleoptera Symptom of damage: Yellowing and gradual wilting of entire plants. Nature of damage: Grubs feed on the roots of rainfed crop. Adult: Black coloured shiny beetle.'
77
67
'Pupa: Pupation takes place in hard chitinous puparium, which is found sticking to the side of pod or in the groove eaten into the grain by the larva. It is cylindrical with broadly rounded ends. Fresh pupa is yellowish white, but becomes darker subsequently. Adult: It is slightly bigger than the male. Its wings are also slightly broader. Colour of a newly emerged adult is dull-white and smoky patches at places, but gradually it acquires the normal black colour with slight bright greenish tinge. Abdomen is glossy black, but in some cases it is slight bronzy, while ins other cases it has a greenish-blue background.'
78
95
'13. Thrips, Caliothrips indicus , Thripidae, Thysanoptera Symptom of damage: Older/lower leaves showing white spots/marks or streaks intermingled with black excreta on the upper surface. Nature of damage: Nymphs and adults suck the sap from tender shoots. Nymph and Adult: Dark blackish brown with fringed wings. Forewings have three pale white coloured bands.'
79
96
'14. Thrips , Scirtothrips dorsalis , Thripidae, Thysanoptera Symptom of damage: Tender leaves showing yellowish green patches on the upper surface and brown necrotic areas and silvery sheen on the lower surface. Nature of damage: Nymphs and adults suck the sap from tender shoots. Nymph and Adult: Creamy to white nymph and black adult.'
80
1,463
'Tea means tea other than Kangra tea obtained by acceptable processes, exclusively from the leaves, buds and tender stems of plant of the Camellia sinensis (L) O.Kuntze. It may be in the'
81
36
'10. Earhead bug : Calocoris angustatus : Miridae: Hemiptera Symptom of damage: No external symptom will be visible. The earheads should be tapped either on the palm or a piece of cardboard. A number of brownish or greenish nymphs and adults can be seen. On the developing grains small brownish spots will be visible. In severe infestation, the grains get shriveled without maturing and the earheads appear uneven. Nature of damage: The adults and nymphs live inside the earhead and suck the milky fluid from the tender ripening grains. Due to the feeding, the grains get shriveled and chaffy and thus unfit for sowing and for consumption. No damage is caused to fully ripened grains. A reduction of 15 – 30% in the yield was estimated due to its attack. Usually high yielding varieties with compact earheads (Chitrai cholam) are subjected to more infestation than the loose earheads. Egg: The female bug thrusts shining pale yellowish cigar shaped eggs into the tender tissues of the shoot between glumes in the centre of the florets.'
82
37
'Nymph: The newly hatched nymphs have light orange red abdomen, which changes to green in the advanced instars. Adult: The adult is a slender green elongate bug about 1 cm long and active flier.'
83
38
'12. Sorghum midge : Contarinia sorghicola : Cecidomyidae: Diptera Symptoms of attack: The flowers appear damaged; earheads are devoid of grains and during severe attack, may appear blighted. Nature of damage: This fly attacks the developing grains. The larvae develop by feeding inside the grains. This results in the failure of grain formation causing them to shrivel during serious infestation the entire earhead may appear to be blighted or blasted. This pest is a minor pest and assumed major pest status after the introduction of CSH 1 hybrid cholam. Egg: Eggs are laid inside the glumes of closed or open flowers. Maggot: The newly hatched maggot feed on the ovaries. The advanced stage larvae are pink in colour. Pupa: pupate inside the damaged flowers. Adult: The midge is a tiny (2 mm long) pinkish coloured fly.'
84
187
'28-56 d Total life cycle : 25 d A 7-8 d P Symptom of damage: Presence of round tunnel (1 mm) in grains and root crops. In bagged storage irregular messy waste flour spots indicate infestation of the pest. Presence of frass, shelled grains and foul smell. Nature of damage: Heating is very common. Infestation is confined to a small area. Grubs and adults cause damage and are voracious feeders. Adults reduce the grain kernels to mere frass. Grubs eat their way into the grain or feed on the grain dust or starchy material and are capable of attacking grain externally. Egg: Eggs are laid on the surface or on the interstices of cereal grains singly or in clusters. Grub: White, apodous with brown head, free living upto 3 rd instar. Pupa: Grub enters the grain after 3 rd instar for pupation. Adult: Brown to blackish beetle, head is deflexed downwards below prothorax to such an extent that it is almost hidden in a dorsal view. There is a prominent constriction between prothorax and elytra. Antenna clubbed with large loose three-segment.'
85
1,464
'form of black or oolong tea. The product shall have characteristic flavour free from any off odour, taint and mustiness. It shall be free from living insects, moulds, dead insects, insect fragments and rodent contamination. The product shall be free from extraneous matter, added colouring matter and harmful substances.'
86
40
'1. Pink borer, Sesamia inferens , Noctuidae, Lepidoptera Symptom of damage: Deadheart. Nature of damage: Larva congregate inside the leaf whorls and feed on the central leaves causing typical ‘pin hole’ symptom. Severe feeding results in drying of the central shoot and results in dead heart formation. Egg: Creamy white spherical eggs laid in batches in between leaf sheaths and stem of the plant. Larva : Pinkish brown with a reddish brown head. Pupa: Brown, obtect pupa, pupates inside the stem. Adult: Straw coloured moth with forewings having 3 black spots and a faint brown mid-stripe with white hindwings.'
87
41
'2. White borer, Saluria inficita , Phycitidae, Lepidoptera Symptom of damage: Deadheart. Nature of damage: Larva found at the base of tillers close to soil level and attack the basal parts of the plants. Larva: Creamy white with yellow head. Pupa: Brown, obtect type, pupates inside the stem. Adult: Small moth with dark brown forewings bearing a white band along the anterior margin and white hindwings.'
88
42
'3. Cutworm, Spodoptera exigua , Noctuidae, Lepidoptera Symptom of damage: Defoliation in the nursery. Nature of damage: Larva feed on leaves especially in the nursery. Larvae hide in the soil during daytime and feed on leaves at night. Egg: Lays cluster of eggs on the lower portion of young plants. Larva: Brownish green with wavy lines in dorsal surface and lateral yellow stripes. Pupa: Pupates in the soil in earthen cocoons. Adult: Brown moth with white hindwings.'
89
43
'4. Black hairy caterpillar, Estigmene lactinea , Arctiidae, Lepidoptera Symptom of damage: Defoliation. Nature of damage: Larva feeds on the leaves. Egg: Eggs are laid on the plants. Larva: Thick with black head and hairs all over the body. Pupa: Pupates in soil. Adult: Large white moth with crimson markings on head, body and wings.'
90
44
'Symptom of damage: Shot holes in the leaves of young plants. Nature of damage: Adult bites and makes holes in the leaves of young plants and affects their vigour both in the nursery and in the young transplanted crop. Adult: Dark blue beetle with enlarged hind femur.'
91
45
'6. Wingless grasshopper , Neorthacris simulans , Acrididae, Orthoptera Symptom of damage: Defoliation. Nature of damage: Nymph and adult defoliate the crop. Adult: Greenish brown colour with a red stripe on the sides; without wings.'
92
46
'8. Aphid, Hysteroneura setariae , Aphididae, Hemiptera Symptom of damage: Presence of colonies of aphids on leaves and ears. Nature of damage: Nymph and adult suck the sap. Adult: Brown coloured aphids.'
93
232
'5. Ripening -Ripening before processing may be required for certain fruits such as avocado, banana, kiwifruit, mango, nectarine, papaya, peach, pear, plum, melons, etc. that are picked immature. Ethylene treatment can be used to obtain faster and more uniform ripening. The optimum temperature range for ripening is 15-25 C and'
94
50
'4. Phadka grasshopper , Hieroglyphus nigrorepletus , Acrididae, Orthoptera Symptom of damage: Leaves defoliated from the margin; plants often bared. Nature of damage: Nymph and adult feed on the leaves and shoots. Egg: Gravid female trails its abdomen on the ground searching for a soft moist spot. It drills a hole with its ovipositor, inserts the abdomen with ovipositor, secretes a fluid and lays the eggs one by one. The fluid hardens into a capsule or egg-pod containing 30-40 eggs. Nymph and Adult: Have green and brown forms, the brown being the most common form. Both have a conspicuous irregular black dorsal pronotal stripe. Adults mostly brachypterous.'
95
51
'5. Stem borer, Chilo partellus, Crambidae, Lepidoptera 6. Pink stem borer, Sesamia inferens , Noctuidae, Lepidoptera 7. Webworm, Cryptoblabes gnidiella , Pyraustidae, Lepidoptera 8. Cutworm, Mythimna separata , Noctuidae, Lepidoptera 9. Cutworm, Spodoptera exigua , Notuidae, Lepidoptera 10. Ash weevil, Myllocerus spp., Curculionidae, Coleoptera 11. Leaf hopper , Pyrilla perpusilla , Lophopidae, Hemiptera 12. Aphid , Rhopalosiphum maidis , Aphididae, Hemiptera 13. Shoot bug , Peregrinus maidis , Delphacidae, Hemiptera'
96
52
'1. Shoot fly, Atherigona approximata , Muscidae, Diptera Symptom of damage: Dead hearts in young plants; corkscrew or chaffy grains in the upper portion and well-developed grains in the lower portion of earhead in mature crop. Nature of damage: Maggot damages the growing point and causes ‘dead heart’. It injures the leaf blades as well as the young shoots and tillers. It also infests the peduncle of earhead at the time of emergence from boot-leaf, preventing seed setting at advanced stage of crop growth. Egg: Eggs are laid on the shoots near the soil surface. Maggot: White cylindrical maggots. Pupa: Puparium brown colour, pupates inside the stem. S Adult: Greyish white fly.'
97
53
'2. Earhead midge, Geromyia penniseti , Cecidomyiidae, Diptera Symptom of damage: Grainless glumes with white pupal case attached to the tip of the spikelet. Nature of damage: Maggot attacks developing grains and feed on the ovaries. As a result of their feeding grain formation is affected and in case of heavy infestation entire head appear to be aborted. Egg: Eggs are laid singly or in pairs in spikelets and may be found sticking to glumes. Maggot: White cylindrical maggots. Pupa: Puparium brown colour pupates inside the spikelet. Adult: Light pink, fragile fly.'
98
54
'3. Leaf beetle, Lema downsei , Galerucidae, Coleoptera Symptom of damage: Whitening and drying of leaves leading to burnt up appearance. Nature of damage: Grub and adult scrape the green matter of leaves in rainfed crop causing whitening and ultimate drying. Egg: Eggs laid singly on the leaf tissue. Grub: Whitish with a black head, swollen humped body and has the habit of carrying its faecal matter dorsally. Pupa: Pupation takes place inside the soil. Adult: Straw coloured beetle.'
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'3. Gram blue butterfly , Euchrysops (Catochrysops) cnejus , Lycaenidae, Lepidoptera Symptom of damage: Presence of regular, big, circular borehole on the flowers and pods. Presence of flat slug like green coloured larva on affected flowers or young pods. Black ants hovering around the plants. Nature of damage: Larva bores into the buds, flowers and green pods and feeds inside the developing grains. Egg: Laid on flower buds, green pods, shoots and leaves. Larva: Flat, slug like, green or yellowish green, red coloured mid stripe and few hairs. Pupa: Pupates in soil or on the plants Adult: Blue coloured butterfly having five black spots on the dorsal surface of the hind wing and two black spots on the ventral surface.'
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