Sunflower

Insect Management

Introduction Calendar Of Appearance Of Major Insect Pests Of Sunflower In India Common Sunflower Pests Jassids White Flies Aphid Tobacco Caterpillar Head Borer Bihar Hairy Caterpillar Root Weevil Integrated Pest Management Of Sunflower Integrated Management Hints Crop Rotation Fertility Management Sanitation Planting Date Tillage Sucking Pests Defoliators Inflorescence Pests Seedling Pests Soil Insects Storage Pests

Introduction

  • Sunflower (Helianthus annuus L.) has contributed significantly to the increased oilseed production in the country during nineties.
  • The cultivation of sunflower which was confined to southern part of the country has now expanded to northern part.
  • A diverse assemblage of both beneficial and harmful insect species are associated with sunflower crop.
  • As many as 251 insect and acarine species are known to attack sunflower crop worldwide.
  • In India, more than fifty insect species have been found feeding on sunflower of which seedling pests, cutworm (Agrotis spp) and grasshopper (Atractomorpha crenulata), soil insects (termites and whitegrubs), sucking pests such as leaf hopper (Amrasca biguttula biguttula), whitefly (Bemesia tabaci), thrips (Scirtothrips dorsalis), defoliators like Bihar hairy caterpillar (Spilosoma obliqua), tobacco caterpillar (Spodoptera litura), green semilooper (Plusia orichalcea), cabbage semilooper (Trichoplusia sppi) and capitulum borer (Helicoverpa armigera) are of economic importance.
  • Non insect pests such as rabits, parakeets, doves, house sparrows, crows, rats etc. have been reported to cause severe damage on sunflower.
  • However, the number of species of major pests requiring management strategy vary from region to region.
  • Various pest species damage different parts of sunflower plant.
  • Soil insects damage roots and emerging seedlings.
  • Defoliators and sucking pests cause loss in food reserves.
  • Infloresence pests destroy floral parts, ovaries and developing seeds and cause direct damage.
  • Storage insect pests damage endosperm and embryo thereby prevent their proper germination and depress quality and quantity of seed oil.
  • Damage by insects predisposes plants to various diseases through affected parts.

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Calendar Of Appearance Of Major Insect Pests Of Sunflower In India

Sl.No. Insect pests and diseases Crop stage Pest status
1. Cut worm, (Agrotis segetum ) Seedling Severe
2. White fly, (Bemisia tabaci ) Seedling and Vegetative Severe
3. Green jassid, (Amsacta biguttula biguttula) Seedling and Vegetative Severe
4. Tobacco caterpillar, (Spodoptera litura and S.exigua) Seedling and Vegetative Severe
5. Shield bug, (Galeatus scrophicus) Vegetative and flowering -
6. Semilooper, (Plusia orichalcea ) Vegetative Regular
7. Capitulum borer, (Helicoverpa armigera) Vegetative and flowering Regular
8. Bihar Hairy caterpillar, (Silosoma obliqua ) Foliage Severe

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Common Sunflower Pests

Seedlings and root pests

Scientific name Common name Distribution
Agrotis spp. Cutworms Cosmopolitan
Amsacta lactinea Tiger moth Asia
Euphoria boliviensis Scarab South America
Meloidogyne spp. Root knot nematodes Widespread
Tanymecus dilaticollis Mite USSR ,Europe
Stem pests
Heterobychus spp. Stem borer East Africa
Melanagromyza spp. Stem girdler Widespread
Foliage pests
Aphis gossypii Cotton aphid Africa , Australia , Asia
Amrasca b. bigutulla Jassid Asia
Anuraphi helichrysi Aphis USSR , Europe
Diacrisia obliqua Hairy caterpillar India
Empoasca spp. Jassids Africa
Heliothis spp. Bollworms Cosmopolitan
S. litura Leafworm Asia , Australia
Flower and fruit pests
Heliothis spp. Bollworm Cosmopolitan
Nezara viridula Green shield bug Cosmopolitan
Storage pests
Sitophilus spp. Granary weevils Cosmopolitan
Tribolium castaneum Red flour beetle Cosmopolitan

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Jassids

Scientific Name: Empoasca kerri
Order: Hemiptera
Family: Cicadellidae

This insect pest has been reported from Maharashtra, Andhra Pradesh, Telangana, Karnataka and Tamil Nadu.

Seasonal occurrence

  • Widely distributed
  • Mostly seen at seedling stage, some times found almost throughout the year.

Life History

  • Nymphs are pale greenish almost translucent and walk diagonally.
  • Adults are greenish yellow, wedge shaped with a pair of black spots on vertex and a black spot on each of the forewings.
  • Female inserts eggs into leaf veins on the underside.
  • Eggs hatch in 6-10 days and nymphal period is 7-9 days and the winged adults live for 2-3 weeks.
  • Completes 7-8 generations in a year.

Nature of damage

  • Nymphs and adults suck sap usually from the under surface of the leaves and inject toxins causing curling of leaf edges and leaves turn red or brown. The leaves dry up and shed.
  • Economic threshold; 2-3 Jassids per leaf.

Control

  • Spraying with any systemic insecticide.
  • Seed treatment with imidacloprid or carbosulfan or spraying of monocrotophos protects the crop from all sucking pests including Jassids for about a month.

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White Flies

Scientific name: Trialeurodes sp.
Order: Hemiptera
Family: Aleyrodidae

  • In recent years white flies are becoming a serious pest in Andhra Pradesh, Telangana, Karnataka, Tamil Nadu and Maharashtra.
  • In Tamil Nadu, the white fly is found round the year but it takes on a serious proportion from March to June.

Seasonal occurrence

Highly Polyphagous generally appears from November to February.

Life cycle


Nymph
  • The insect breeds throughout the year and the female lays stalked yellow spindle shaped eggs singly on the lower surface of the leaf.

Adult
  • Eggs hatch in about a week’s time.
  • The nymphal stage remains attached on the lower side of leaves and takes about 4 weeks to complete development.
  • Number of generations varies between 12-15 per year.
  • Nymphs are oval, scale like and remain attached to the leaf surface.
  • Adults are tiny, moth like with yellowish body and wings coated with milky white waxy powder.

Nature of damage

  • Nymphs and adults suck the sap usually from the under surface of the leaves and excrete honeydew.
  • Leaves appear sickly and get coated with sooty mold.Stunted plant growth, shedding of fruit bodies, It also transmits the leaf curl virus.

Ecology

  • Temperatures around 300 C with high humidity favours multiplication of pest.
  • Economic threshold: 8-10 adults or 20 nymphs/leaf.

Control

  • Whiteflies can be effectively attracted and controlled by yellow sticky traps, which are coated with grease/sticky oily materials.
  • Spray Triazophos (2.5 ml/l) or Prophanophos (2 ml/l).
  • Spraying of any Neem product (5% Neem oil before egg laying) or 5 kg Neem Kernal extract per acre with any sticky material.
  • Use of Synthetic pyretheroids increases the intensity of Whitefly.

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Aphid

Scientific Name: Aphis craccivora
Order: Hemiptera
Family: Aphididae

It is a major pest in Andhra Pradesh,Telangana, Maharashtra, Tamil Nadu and Karnataka.

Seasonal occurrence

Polyphagous pest, widely distributed

Life cycle

  • Nymphs are light yellowish green or greenish black or brownish.
  • Adults are mostly wingless but few winged forms also seen.
  • Winged and wingless forms breed parthenogenetically and hence population build up is quite fast.
  • It has 12-14 generations per year.

Nature of damage

  • Nymphs and adults colonise on the under surface of the young leaves, shoots and suck the sap resulting in crinkling and curling of leaves.
  • Leaves appear shiny and sticky due to honeydew excreted by the insects. Later sooty mold grow on honey dew and leaves have a black coating.

Ecology

  • Cool and humid conditions are favourable for multiplication while heavy rains wash away the aphid colonies.
  • Economic threshold limit is 15-20% affected plants.

Control

  • Seed treatment with Imidacloprid (5g/kg seed) keeps the crop free of sucking pests over a month.
  • Dimethoate or methyl Demeton or Phosphamidon can be used for control.
  • Paint on stem with a mixture of Monocrotophos: water (1:4) or Imidacloprad: water (1:20) at 20, 40 and 60 days age of crop.

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Tobacco Caterpillar

Scientific name: Spodoptera litura
Order: Lepidoptera
Family: Noctuidae

  • Distributed in all parts of Sunflower growing areas.
  • This is a polyphagous pest having a wide host range.

Seasonal occurance

Polyphagous and cosmopolitian

Life cycle

  • Moth lays eggs on the underside of leaves in masses (100-300) and covered with brown hair.
  • Each female lays 1000-2000 eggs.Eggs hatch in 3-5 days.
  • Larval stage completed in 28 days.
  • Pupation takes place in the soil and pupal period lasts for about 9 days.
  • Longivity of adults is 9-10 days. Has 6-8 generations/year.

Nature of damage

  • Soon after hatching, early instar larvae feed gregariously by scraping the chlorophyll of Lamina leading to skeletonization.
  • Later they disperse, become solitary and nocturnal.
  • Also feed on the flower buds, flowers, calyx.
  • Economic threshold: 5-10% incidence level in retained and shed fruiting bodies.

Control

  • Use of Pheromone traps (4 traps/acre) for pest intensity identification as well as to trap the male moths.
  • If eight egg masses observed per 100 m row of crop-spray 5% Neem Kernal extract preferably in the evening.
  • Spray Chloriphyriphos or Endosulphan or Quinalphos @ 2 ml/l of water.
  • Add and mix one liter of Monocrotophos or one kg of Carbaryl and 1 kg of Jaggery with 10 kg of rice bran.
  • Mix with water and made into small balls and keep the balls at each plant.

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Head Borer

Scientific Name: Heliothis armigera
Order: Lepidoptera
Family: Noctuidae

  • This is a polyphagous pest and distributed widely.
  • It causes damage to a number of crops.
  • The young larva enters inside the sunflower head in the centre and starts feeding.
  • Heads are damaged seriously causing a huge amount of field loss.
  • The eggs are laid singly on leaves or flower heads. Young larvae feed on the leaves and on the head.

Seasonal occurrence

It is active throughout the year.

Life cycle

  • The female moth lays shining, cream, colored eggs singly on tender parts of the plant.
  • Each moth lays 730-3000 eggs. The eggs hatch in 4 days.
  • The larvae become full-grown in 17-20 days.
  • Pupation takes place in soil for 10-13 days.
  • There may be as many as 7-8 generation/year.

Nature of damage


Larva boring into head

  • The larva damages by boring into, flowers and feeds on inner contents, while feeding it thrusts it head inside the leaving the rest of its body outside.
  • The entry hole is large and circular.
  • 8-9 moths per pheromone trap/day, or 5 eggs/10 plants or 1 larva/plant or 5-10% infested fruiting bodies.

Control methods

Cultural methods


Sunflower inter cropped
with groundnut
  • Recommended doses of fertilizers should be applied.
  • Inter crops like, Green gram, Black gram, Groundnut, Soybean should be sown.
  • Sow 3-4 lines of maize (or) Jowar around the sunflower crop to monitor the moth.
  • Sow trap crops like marigold at 50 plants/acre along with sunflower.

Physical methods

  • Collection & destruction of eggs on trap crop as well as main crop.
  • Collection & destruction of larvae on trap crop as well as main crop.

Mechanical Methods


Pheromone trap
  • Use of pheromone traps (4 traps/acre) for pest intensity identification as well as to trap the male moths.
  • Setting of light traps (1 light trap/5 acre) to know the range of pest incidence as well as to kill moth population.
  • Arrange 10-bird perches/acre.

Biological methods

  • Trichograma pretiosum attacks on eggs of Heliothis.
  • Release Trichogramma parasites @ (20,000/acre)
  • Eucelatoria byrani; Carcelia illota attacks on larvae of Heliothis.
  • Bacillus thuringenisis (soil bacteria)
  • NPV (virus)
  • Beauveria bassiana (fungi)
  • Nomuraea rileyi (fungi)

NPV:

NPV 200 LE + 1 kg Jaggery + 200ml Sandovit (or) Teepal; mixing and spray in the evening hours only;

NPV is more effective in cloudy weather.

Bio-pesticides

  • Spraying 5% Neem oil before egg laying.
  • 5 kg Neem Kernal extract /acre. Add any sticky material to spray mixture.

Chemical Control

  • Monocrotophos 2.0 ml/lt of water
  • Endosulfan 3 ml/l of water
  • Quinalphos 3m/lt of water
  • Propenophos 2m/lt of water
  • Chlorophyriphos 2.5m/lt of water
  • Carboryl 1kg/acre.
  • Fenvalrate 250 m/acre
  • Cypermethin 10 EC 400 ml/acre
  • Decamethrin 2.8 EC 300 ml/acre

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Bihar Hairy Caterpillar

Scientific Name: Spilosoma obliqua
Order: Lepidoptera
Family: Arctiidae


Early larva
  • This insect has been recorded from all sunflower growing areas.
  • This is a polyphagous pest.
  • Young larvae feed gregariously mostly on the under surface of the leaves.
  • A caterpillar of later stages defoliates the field completely and moves to the next field.
  • Hundreds of eggs are laid by the female on the lower leaf surface in masses.
  • Eggs hatch within three to four days.
  • Larvae become full grown in 15 to 20 days.
  • Full grown larva is about 5 cm long.
  • Pupation takes place on the soil under dry foliage- and debris.
  • The pupa forms a thin silken Cocoon by interwoven shed hairs of the larvae.
  • Only one to two instar larvae can be controlled by insecticide spray.
  • Spray Monocrotophose or Quinolphose @ 1.5 ml/lit of water.

Late larva

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Root Weevil

Scientific Name: Myllocerus discolor
Order: Coleoptera
Family: Curculionidae

  • The pest is distributed all over the sunflower growing areas of the country. Damage is caused by both grub and adults.
  • Grubs feed on roots whereas adults feed on the margin of the leaves.
  • Damage caused by grubs is more than by the adult. Plants collapse and die due to grub damage.
  • The female lays about 300 eggs singly or in groups .
  • Hatching takes place after three to seven days of incubation The grubs feed on roots and become full grown in about 10 days.
  • The pupation takes place in an earthen cell at a depth of 5 to 7 cm. Pupal period usually varies from five to seven days.
  • Sometimes pupae remain in the soil in diapause until the next year.
  • The weevil is grey.
  • Control may be achieved by use of any chlorinated hydrocarbons.

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Integrated Pest Management Of Sunflower

  • In India cultural practices were the important tools for pest management in traditional agriculture.
  • The farmers continued to follow these practices until the advent of pesticides.
  • Actually speaking the pesticides were evolved to supplement the cultural practices, but they have supplant them, which in turn has led to many hazardous to the environment and human health, such as increased resistance of pests to pesticides, change in pest status, destruction of natural enemies, contamination of environment, hazards to human health and de-stabilization of natural eco-system.
  • The world-wide awareness of safe environment provided impetus to foster non-chemical pest management strategies.
  • Of these, cultural methods constitute the most farmer-oriented approach, where the weak points in the biology and behaviour of insects are exploited and pressure is exerted on the population by manipulating the environment.
  • Farmers have been modulating a crop growth through adjustments in time of sowing, cultural practices and plant population density.

The cultural practices may influence pest in four ways


Use of pheromone traps

Removal of stubles

Removal of affected leaves

Summer ploughing
  • Practices like flooding, summer ploughing, solar heating (solarization), crop rotation or soil amendment reduce inoculum potential.
  • Use of healthy seed, sanitation, field levelling reduces initial pest load.
  • An optimum use of irrigation, plant density and nutrients minimises host susceptibility.
  • Isolation of field or mixed cropping promotes pest escape.
  • Under Indian conditions, cultural practices are one of the strong IPM components which are of immense importance because of low cost inputs, easy in adoption and acceptance by farmers.
  • Cultural practices like summer ploughing, sanitation, tillage, crop rotation, intercropping, fertility management, planting date, barrier crops, spacing, soil moisture and irrigation management are very important low cost IPM components which help in sustainable production of sunflower crop apart from maintaining ecological balance.

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Integrated Management Hints

  • Since sunflower crop attracts several species of beneficial insect fauna hence attention need to be focused on conservation of activity of promising bio-control agents and pollinators by adopting following eco friendly integrated pest management approaches.
  • Summer ploughing which exposes resting stages of insects to predatory birds as well as to hot sun.
  • Seed treatment with imidacloprid keeps sucking pests below the threshold level up to 35-40 days after sowing with out affecting natural enemies.
  • Growing sunflower on slopes of ridges of 6-8 cm height would reduce damage due to cutworms.
  • Termites can be effectively managed by killing queen after digging termetorium.
  • Remove alternate hosts which acts as initial source of infestation.
  • Keep field bunds and crop weed free to avoid high pest load as it favours the pest build up on the main crop.
  • Hand collection of egg masses, early and late instar larvae of S.litura and S.obliqua and collection and destruction of late instar larvae of other defoliators and H.armigera.
  • Mixed cropping of sunflower with cotton will result lower thrips and jassid infestation on sunflower whereas H.armigera will be low on sunflower in the sunflower + red gram intercropping system.
  • Spray NSKE (5%) or other neem formulations against defoliators and head borer.
  • Use Spodoptera and Helicoverpa NPV @ 250 LE/ha in case there is an outbreak of pests. NPV can also be used in sequence with NSKE (5%) for effective management of these pests.
  • Release bio-agents,Need based application of pesticides.

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Crop Rotation

  • Continuous cropping encourages carry over of pest population from one planting season to another and favours pest build up and increased infestation leading to severe crop damage.
  • To break the continuity, another crop is planted in between which is not a host or least preferred one.
  • Crop rotations are very effective in breaking this cycle especially for insect pests and diseases of limited host range.
  • Cropping sequence sunflower followed by groundnut reduced downy mildew incidence compared to sunflower followed by sunflower.
  • Introduction of fallow period between successive seasons is often a useful technique to decrease the impact of virulence of the soil pathogens.

Intercropping


Intercropping with redgram
  • Inter and mixed cropping in traditional farming system is an insurance against the risk of crop failure, better utilisation of farm resources and labour and protection from insects.
  • Sunflower is recommended to be grown as crop with redgram, groundnut, ragi and soybean.
  • Sunflower grown with redgram brought down the H.armigera and S.litura populations on sunflower by a small margin compared to other cropping systems.
  • Mixed cropping of sunflower with cotton resulted in lower thrips and jassid infestation on sunflower.
  • Groundnut + sunflower (6:2) intercropping system reduced blight incidence besides being more remunerative than sole crop of sunflower.
  • Losses due to outbreaks of aerial disease will be lowered if multiple varieties are grown especially when large areas are to be grown.
  • Differential response of the hosts to the pathogen can circumvent massive outbreaks and nullify the huge losses.

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Fertility Management

  • Plant growth is dependent on the nutritional status of the soil which in turn has indirect effect on insect pests and diseases.
  • Slight change in the nutritional balance can lead to differential responses.
  • Of the 17 essential elements, the effects of N, P and K have been studied in several cropping systems.
  • Increased application of nitrogen favoured jassid build up and enhanced the development period of H.armigera larvae hence fertiliser application will also help to reduce pest incidence if it is used judiciously.
  • Use FYM or green manure crop has been reported to reduce stem rot severity by nearly 16%.
  • Pathogens like nematodes, Sclerotium, Fusarium, Verticillium, Rhizoctonia are suppressed.
  • Nitrogenous fertilizers are applied to increase yield of crops and this also makes the crop vulnerable to greater infection.
  • Since continuous supply of high nitrogen doses enhances the disease severity, split application is recommended.
  • Application of potash enhances host resistance and efforts are on to standardize the dosages.

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Sanitation

  • Sanitation practices, such as use of healthy seed material, burning and destruction of crop refuge, clean storage, etc., reduce pest population, discourage breeding and hibernating sites and prevent carry over of pest to the next crop/season.
  • Field bunds and crop should be kept clean to avoid high pest load.
  • Sunflower stalk mulched in field was proved to be source of initial inoculum compared to less than 2% disease in no mulch situation emphasising on sanitation of fields.
  • Crop residues in the field are an apt choice for survival and multiplication of facultative parasites like Sclerotina sp., Sclerotium etc.,
  • Heat produced by burning crop residue also reduces number of viable sclerotia by 95%.
  • Residue burning produces an effect similar to solarization, reducing the population of the soil pests.
  • Pupation of defoliators, Plusia orichalcea and Trichoplusia ni takes places on the plant itself hence plant debris should be destroyed to suppress these pests.
  • Selection of seed from healthy crop is primary necessity in development of healthy seed production technique.
  • Many plant pathogens (Alternaria, rusts, Macrophomina, Plasmopara sp.) spread by being externally or internally seed borne.
  • Latent infection in and can lead to epidemics in congenial conditions.

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Planting Date

  • Date of planting takes advantage of the absence of the pest on the crop or when susceptible stage of the crop synchronizes with the most inactive period of the pest or lowest pest population.
  • However, manipulation of planting date is more meaningful if plantings are based on the information obtained from pest monitoring.
  • Timely planting in the rainy season has been demonstrated to be of great value in minimizing alternaria leaf blight of sunflower.
  • Early season planting helps to avoid charcoal rot caused by Macrophomina phaseolina.

Barrier crop

  • Using sunflower as a barrier crop has been earlier advocated in decreasing diseases in short statured crops like groundnut.
  • With the increasing awareness of several disease in sunflower itself, time has come to identify suitable barrier crops like pigeonpea, sunhemp, ragi etc.

Spacing

  • Close spacing in any crop induces more disease due to build up of congenial condition in the plant microclimate.
  • In a broad leaved plant like sunflower foliage is the most vulnerable area of attack.
  • Studies done in AICORPO programme have shown that a spacings of 60x30 cm or 45x30 cm between rows and plants within the row were found to be most optimum in reducing the buildup of alternaria disease.
  • Disease development was found to be more towards flowering and grain filling stage in close spacing.

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Tillage

  • Zero tillage results in high structural diversity because of greater retention of residue on the soil surface which generates greater weed population, in turn favour insect pests and disease incidence.
  • Tillage operations change the texture, nutritional composition and pH of the soil which become less favourable to weeds and soil inhabiting insects and pathogens.
  • Tillage operations destroy weeds which serve as reservoir for pests and may also destroy by burrying part of the population deep under the soil.
  • On the other hand, tillage operations also exposes soil inhabiting fauna to adverse weather conditions and natural enemies.
  • Major pests of sunflower Helicoverpa armigera, Spodoptera litura and Spilosoma pupate in the soil hence summer ploughing may expose pupal stage to predators and adverse weather conditions.
  • Proper preparatory tillag e or field preparation alone can reduce the level of initial pest load.
  • In a tropical country like ours, inherent bountiful solar energy can be well used to check soil borne pathogens like Macrophomina phaseolina, Sclerotium rolfsii, Fusarium spp. apart from resting stages of insect pests.
  • Turning and exposing the soil to solar radiation, suppresses the primary inoculum of these soil borne pathogens.
  • This is of particular use in the downy mildew endemic areas of the Deccan plateau.
  • If the field is not adequately prepared for sunflower, water stagnates in pockets and moist soil favours an early establishment of diseases like downy mildew, damping off, rots, etc. via infested seed or inoculum present in the soil.
  • Often, run off water or droplets can accelerate seedling rots and deaths.
  • Growing sunflower on slopes of ridges (6-8 cms height) would give substantial protection to sunflower seedlings from ravages of important seedling pest Agrotis spp.

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Sucking Pests

  • Sucking pests which are reported to feed on sap of stem and leaves include, leaf and plant hoppers (A.biguttula biguttula; Empoasca sp; Cecadulena.), thrips (S.dorsalis, Thrips tabaci., Arrhenothrips ramakrishnae, Haplothrips ganglbaueri, Megalurothrips usitatus, T.hawaiiensis, Microcephalothrips); aphids (Aphis craccivora, A.nerii, A.gossypii, Uroleucon compositae., Lipaphis erysimi.), plant bugs (Eurybrachys tomentosa., Otinotus lignicola., Oxycarenus laetus, Clavigrella gibbosa, Oxyrachis terandus.) and whitefly (B.tabaci).
  • Among sucking pests, leaf hopper, A.biguttula biguttula appears in serious from causing crop loss up to 46 per cent .
  • The pest is of economic importance in Maharastra, Tamil Nadu and Karnataka.
  • The incidence would start from seedling stage and prevail right through entire plant life.
  • Stunted growth of plant, cupped and crinkled leaves, burnt appearance of leaf margins are symptoms of damage.
  • Low Relative humidity and high daily maximum temperature was found to have significant positive correlations with its population.
  • Summer crops are likely to suffer more with this pest than kharif crop.
  • Increased Nitrogen-supply to the crop favoured jassid buildup probably due to increased leaf area which are directly correlated.
  • Increased spacing also encouraged jassids buildup.Sunflower crop is a reservoir of several species of coccinellids viz., Brumus suturalis., Chilochorus nigritus., Coccinella septumpunctata., Menochilus sexmaculata, which keep a good check on sucking pests like thrips, aphids and jassid nymphs.
  • Some germplasm lines showed promise against jassids (KBSH-8, BSH-1, S-55, EC-61039, 75268M, 77195, 110737, 35811), whiteflies (EC-93442) and thrips (EC-101287 and EC-68414) either by supporting comparatively lesser population or not expressing cupping symptoms compared to susceptible ones.
  • Mixed cropping of sunflower with cotton resulted in comparatively lower thrips and jassids infestation on the former.
  • Any one of the insecticides like phosphamidon (0.03%), dimethoate (0.03%) and monocrotophos (0.05%) may be sprayed @650-700 lit spray solution per hectare if the sucking pest build up is very high.
  • Seed treatment with imidacloprid @5g /kg of sunflower seed gave protection from jassid up to 35-40 days after sowing.
  • Among several botanicals evaluated, neem seed kernel extract was found to be most effective against jassids.

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Defoliators

  • Major defoliators include lepidopterans, weevils, beetles and grasshoppers among them lepidopterans constitute major defoliator complex in which S.obliqua, Diacrisia casignetum, S.litura, S.exigua, Estigmene lactinea, Duproctis fraterna, E.virguncula, P.ricini, Plusia signata, P. orichalcea, (Thysanoplusia orichalcea), Cirphis loreyi ,Perigoea capensis are important and there have been reports of outbreaks in case of S.obliqua.
  • Among other defoliators, grasshoppers some times cause considerable defoliation at early stage of the crop.
  • Different species of weevils which feed on sunflower are Myllocerus maculoses, M.discolor, M.dentifer, M.viridanus. and Ptochus ovulum.
  • Beetles like Pacnephorus bretinghami and Aulacophora faevicillis were also reported to cause defoliation.
  • The loss in seed yield due to defoliators in a rainfed Kharif crop was up to 268 kg/ha at Bangalore.
  • Weevils, grasshoppers and jassids caused 37.5% loss in seed yield at Coimbatore.
  • If the defoliators attack is before flower initiation it would affect food partitioning between stem, leaves and roots and if it is later it would affect growth of both vegetative parts and inflorescence.
  • Severe defoliation during flower initiation results in heavy reduction in the assimilate supply to capitulum thereby upsetting floret production and its survival.
  • Defoliation during seed set increases stem breakage due to high levels of mobilisation of stem reserves to capitulum and also diminishes seed set.
  • Active leaf area is also essential for seed filling S.obliqua is highly polyphagous and occurs all over India and often reported to cause colossal damage to sunflower Spodoptera may also assume injurious levels similar to S.obliqua.
  • Both S.obliqua and S.litura lay eggs in masses on underside of leaves and early instar larvae are gregarious.
  • Gregarious form while feeding on underside of leaves give "mesh" like appearance to leaf which can be easily located, collected and destroyed by scouting across the field.
  • S.litura usually occurs in late kharif as indicated by pheromone trap catches.
  • Above moths are attracted to light hence can be trapped by a light trap.
  • Although, these pests occur regularly on sunflower with occasional outbreaks they remain well below the ETL most of the times in south India.
  • Both of them pupate in plant debris and S.litura also pupates in soil as well hence summer ploughing will expose pupal stage to predators.
  • In nature several parasitoids, predators and microbial agents occur on S.obliqua and S.litura.
  • P.orichalcia.usually begin to attack the vegetative phase of the crop.
  • Plusia lays eggs singly preferably on under side of leaves concentrating more on mid canopy.
  • The moths are attracted to light.
  • The pupation takes place on plant itself so plant debris should be destroyed to suppress this pest.
  • This has become more serious a defoliator on sunflower than others in South India.
  • Grass hoppers, weevils and beetles occassionally may cause economic damage to crop and they can be managed by clean cultivation and keeping bunds clean and application of any one of the dust formulation of insecticides.
  • If there is outbreak of these defoliators methyl parathion 2% dust @25kg/ha may be dusted or endosulfan 0.05% @650-700 lit of spray solution/ha may be applied.

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Inflorescence Pests

  • Capitulum borer H.armigera is the most serious among inflorescence pests.
  • The minor inflorescence lepidopteran pests are Chloredia obsolata., P.recini, H.peltigera, beetles such as Oxycertonia versicolor., Careydon gonagra Fab. and Oryzaephilus sp.
  • plant bugs Dolycoris indicus, Eurybrachys tomentosus, Campylomma livida., Otinotus lignicola., Leptacentrus substitutus, Nazara virudula., Aphanus sordidus, G.serophicus, Lygus civilus., Nysius sp., Graptostethus servus, O.laetus, Stengygum sp. Calocorus ungustatus., Cletus signatus., Dalpada pillicornis, Eusarcocris guttiger and Leptocorysa acuta.
  • The capitulum borer H.armigera is highly polyphagous with about 181 host plants including important crop plants such as pulses, cotton, vegetables etc., and the pest is prevalent throughout Africa, Asia and Australia.
  • It is causing direct damage to receptecle, ovaries, developing seeds and the resulting loss in seed would spill over 50 per cent.
  • This pest has developed resistance to most of the commonly used insecticides in cotton ecosystem and therefore it is imperative to take care of sunflower from this dreaded pest.
  • There are reports of outbreak of Helicoverpa on sunflower in northern parts of Karnataka during 1997 kharif season.
  • Altogether 77 parasatoids and 33 predators have been reported on this insect in different crops.
  • In Sunflower predators such as chrysoperla carnea, Minochilus sexmaculatus and parasatoids such as Bracon spp., Campoletis spp., and Trichogramma spp., have been found to be predominent.
  • Occurrence of several predators on this pest have been reported by various workers. and coccinellid beetle complex in north India are predominant key mortality factors of this pest.
  • Diseases such as NPV, muscardine (white and green) have often noticed in the field populations of lepidopteran pests.
  • A significant reduction in pest density is achieved with the spray of NPV @250 LE/ha. NPV @ 250 LE/ha with UV protectants gave better protection than local NPV without UV protectants.
  • Three sprays of NPV @ 500 LE/ha brought down pest population completely and recorded highest yield.
  • It is important to mix UV-protectants with NPV formulation and to apply it in the evening hours Bt. liquid formulation @ 2 lit/ha reduced head borer damage with increase in yield.
  • Coverage of capitulum and upper plant parts thoroughly with NPV + Bt. would give better results.
  • Cultural practices are important components of IPM. Sunflower is recommended to be grown as inter crop with redgram, groundnut, ragi and soybean.
  • Sunflower grown with redgram brought down the borer population on sunflower by a small margin compared to other cropping systems.
  • Helicoverpa male adults can be attracted to sex pheromone traps.
  • The light trap also attracts moths of both sexes.
  • The knowledge of adult behaviour would help in supplementing the other management practices.
  • Many neem origin botanicals have been evaluated against H.armigera on other crops but on sunflower there is very little information.
  • Application of neem seed kernel extract and neem based pesticides will not only reduce damage due to Helicoverpa but also helps in conserving the activity of natural enemies as well as honey bees.
  • A particular crop stage usually be more vulnerable to a given pest and control measure exercised at this stage is more economical.
  • The experiment on this aspect revealed that a chemical spraying at 40 days after sowing (DAS) is most crucial to suppress this pest.
  • Further, considering the borer population, yield and B/C ratios spray of endosulfan (0.05%) on 25 and 45 DAS is ideal for management of this pest in a short duration variety like Morden.
  • Many insecticides have been screened for their eficacy among them phosalone (0.05%), endosulfan (0.05%), fenvalarate (0.005%), monocrotophos (0.05%), cypermethrin (0.005%) spray @ 650-700 lit/ha, methyl parathion (2%), quinalphos (1.5%) and endosulgan (4%) dust @ 25 kg/ha may be used against the head borer and were found to be most effective among the insecticides screened by several workers.
  • The use of these should be need based and their application should be avoided after anthesis as this would cause toxicity to pollinators.
  • Honeybees play very important role as pollinators which are essential to bring about cross pollination in sunflower.
  • The insecticidal application at bud stage of the crop, that is when Helicoverpa eggs appear on them is most ideal one to contain it.
  • It is advisable to spray the crop when the borer larval number exceeds its ETL level of 4.25 larvae per 10 capitulum.
  • Spraying in evening hours and use of insecticides such as endosulfan and phosalone would safe guard bees.

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Seedling Pests

  • Several pests have been found to cause severe damage to sunflower crop during seedling stage among them, most important are cutworms, Agrotis ypsilon Rott, Aflammetra SchifferMueller and the tenebrionid, Gonocephalum sp. Which cut the seedlings as they emerge.
  • Cotton seedling weevil Atactogaster finitimus also damages seedlings.
  • In recent years the cutworm, Agrotis spp. is gaining importance in Punjab, Haryana and Karnataka.
  • The damage may go upto 20 percent.
  • The pest is more serious if sunflower is grown after potato.
  • Some times grasshoppers cause considerable damage to seedlings.
  • Dove, field rats, crow, rabbit and stripped squirrel also damage germinating seedlings or pick up sown seeds.
  • As a result of severity of seedling pests some times the plant stand of sunflower crop will be reduced up to 30 percent.
  • In endemic areas integration of the following management practices may be followed for reducing damage due to cutworms.
  • Summer ploughing of field to expose resting stages of seedling pests.
  • Growing sunflower on slopes of ridges (6-8cms height) would give substantial protection to sunflower seedlings from ravages of cutworm.
  • Chemicals like aldrin (30 EC), chlorpyriphos (20 EC) and imidacloprid (25 UP) also give good control when mixed with soil.
  • Lindane (20 EC), phorate (10 G) and diazinon (25 EC) were also found effective against cutworms.
  • Monocrotophos bait prepared in rice bran is quite effective if spread in the field during evening hours.
  • Drenching of endosulfan (0.05%) around seedlings gives good protection against the pest.

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Soil Insects

  • Termite (Odonototermes obesus) and whitegrubs were reported to be serious pests of sunflower in Haryana and caused considerable damage to the crop.
  • Other species such as Odontotermes guptai and, Microtermes obesi. and Eurymotermes paradoxalis also attack sunflower heads when plants fall on maturity due to wind storm.
  • Sub-terranian termites can be controlled by destroying queen either by digging it out or dropping aluminium phosphide tablets inside the termetorium @2 tabs/termetorium of 1m dia or pouring chlorpyriphos 20 EC or aldlrin 20 EC each diluted @60 ml/18 litre of water.

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Storage Pests

  • Sunflower seeds are also susceptible to most of the storage pests infesting other stored commodities.
  • If sunflower seeds are stored with high moisture in uncleaned bins and gunny bags for longer period infestations are very common and enormous loss is expected.
  • There are few predominant insect pests of stored sunflower which includes saw toothed grain beetle (Oryzaephilus surinamensis), red rust flour beetle (Tribolium castaneum) and Indian meal moth (Plodia interpuctella).
  • Rice moth (Corcyra cephelonica) also cause severe damage to stored sunflower.
  • Stored grain pests can be effectively managed by preventing initial infestation following proper sanitation.
  • Sunflower seeds stored for longer period need to be routinely inspected for insects and also hot and moist spots.
  • Aeration to bring the grain temperature down to 50C or less will prevent insect activity.
  • B.thuringiensis can be used for the management of Indian meal moth.

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Andhra pradesh