Wednesday, September 9, 2009

Switching to forefathers’ methods to cut down expense on inputs-M.J. PRABU

Hundreds of cultivable areas are turning into residential plots



cost effective: Namalwar demonstrating the manufacture of herbal tea for crops

“There is a popular adage in English, “give a man a fish he lives for a day, teach him to fish he lives for a lifetime,” This is exactly what our farmers need today.

“Instead of buying external inputs such as seeds, chemical fertilizers and pesticides, they should learn to make and use their own bio pest repellents, and plant growth promoters,” says Dr. G. Namalwar, organic scientist from Tamil Nadu.

If one studies the agricultural scenario of the past 40 years, one observes that hundreds of cultivable areas are turning into residential plots.

Why is this happening in a country with more than 1,500 years of agricultural heritage?

Wrong focus

The answer is simple. The Green Revolution focused more on increased inputs and yields and totally ignored the local and traditional knowledge systems of the farmers.

As a result, in 40 years we lost our native seed varieties, our lands became barren, native birds and insects which helped the crops grow well vanished, water tables started depleting, cross breeding of hybrid cows made several native breeds extinct and there has been more migration towards cities due to unemployment in rural areas.

Not remunerative

Today there is a general view that farming is not remunerative and that a farmer cannot cultivate unless he obtains loans.

“It is true that farming is not lucrative as long as a farmer uses external inputs for growing his crops. On the other hand if he switches to sustainable agriculture as was done by his forefathers then he can definitely cut down a major expense on his input,” he emphasises.

Friendly farming

Hundreds of farmers have realised this truth and have switched over to more environmental friendly farming systems and are reaping good results.

Farmers just need to look around their own fields or village for making any bio inputs.

All the necessary inputs required for their farm are there and there is no need for them to go to the towns and buy, according to Dr. Namalwar. He says that, for example, for making a plant growth stimulant labelled as herbal tea, take an iron, plastic or cement tank and fill it with water (3/4 full).

Take 5 kg of cow dung and any medicinal plant leaves (such as neem, nochi, custard apple leaves), one-fourth kg jaggery and one big stone or brick.

Place all the above mentioned items inside a jute sack, tie the mouth of the sack tightly with a rope and immerse it inside the water.

Leave the other end of the rope free. Shake the sack, holding the free end of the rope two times everyday in such a way that the contents inside the sack mix well with the water (similar to the tea bags immersed in milk).

One week time

In one week the ‘herbal tea’ for the crop is ready for use. It can be either poured directly near the root zone of the crops or sprayed. For one litre dilute in nine litres of water and use.

Amudha Karaisal

Similarly take 1 kg of fresh cow dung, urine and Ipomoea Cornea (Tamil name Neiveli Kattamanakku) leaves each and 25 gm of jaggery. Mix all these well in 10 litres of water and stir well (3 times a day). In 24 hours the solution (Amudha Karaisal, AK) is ready. For use, dilute one litre of AK in 10 litres of water and spray or mix with irrigating water.

But how far are these local systems beneficial in the long run?

“These traditional systems have existed for hundreds of years and only for the past 4-5 decades have they disappeared.

Realised importance

But today our farmers have realised the importance of going back to these systems as they are pocket friendly and effective,” he opines.

Though we have policies which speak out in support of the farmer, sadly they are only on paper and not put in action.

“A farmer must realize that he alone is responsible and answerable for his yield. These systems may look insignificant but their results are proven and have been found effective by a number of farmers,” he says.

For more information readers can contact Dr. G. Namalwar through email: sadhguru@gmail.com and mobile: 94425-31699.

Tuesday, September 8, 2009

Shoot and fruit borer in brinjal

BRINJAL IS prone to attack bythe brinjal fruit and shoot borer, Luecinodes arbonalis.

During the early stages of the crop the larva bores into the shoots resulting in drying and dropping of shoots. On reproduction, the larva bores into the flower buds and fruits and plugs the entrances with excreta.

Control measures

— Collect and destroy the affected fruits and shoots.

— Avoid monocropping and crop rotation with potato.

— Use optimum dose of Nitrogen fertilizers

— Three soil applications of neem cake at 2.5 q ha at the time of transplanting, 1 and 2 months after transplanting.

— Application of neem seed kernel extract (NSKE) 5 per cent.

— Three sprays of insecticides like profenophos 50EC (2ml/l) or thiodiocarb 75 WP (lg/l) or carbaryl 50 WP (2g/l) or malathion 50 EC (2ml/l) during flowering stages at 15 days interval is advised.

S.S. Karabhantanal Anand Hallikeri
& S. Doddagowdar

University of
Agricultural Sciences
Dharwad


Thursday, September 3, 2009

Managing mealy bug menace in custard apple

Custard apple is mainly used as a dessert fruit. Developing fruits are often infested by two species of mealy bugs mainly the striped mealy bug and citrus mealy bug. These mealy bugs are small, pink coloured and soft bodied insects covered with white mealy wax. Nymphs and adults fix their mouth at fissures and furrows of rounded fleshy tubercles of the green fruits. When they infest developing fruits and suck the sap the size of the fruit becomes diminished, shrivelled and undergo premature dropping. These mealy bugs also infest at fruit stalks, leaves and terminal shoots causing, yellowing and drying symptoms.

Pest biology

The pest prefers dry weather and heavy incidence often occurs following periods of prolonged drought. They are active and mobile throughout their life. Reproduction is both sexual and through parthenogenesis, the latter being more common. Females lay 100-300 eggs which hatch into nymphs in 3-4 days. The nymph’s period is around 45 days. The longevity of males is 1 to 3 days while that of females extends from 36 to 53 days.

Management methods

To check the infestation of these pests, remove and destroy the affected leaves, fruits and twigs. Apply diazinon or monocrotophos at 0.1 per cent concentration. Spraying of 5 per cent neem seed kernel extract or 3 per cent neem oil suspension is effective. The soil around trees should be ploughed up to a depth of 75 cm followed by mixing of dust formulation of insecticides such as lindane 1.3 per cent or endosulfan 4 per cent at 10 kg/ acre could be done.

A number of parasites are parasitizing the mealy bugs in nature as biological control agents. Release of Cryptoleamus montrouzieri (ladybird beetle) @ 10 Nos./ tree would be quite effective to predate upon the eggs and nymphs of the mealy bugs.

J. JAYARAJ

& M. ANANTHAN

Horticultural Research Station

Thadiyankudisai, Perumparai, Dindigul

Tamil Nadu

Friday, August 21, 2009

Light traps to capture caterpillar moths in coconut

Among different caterpillars that feed on coconut leaves, the slug
caterpillar can cause sporadic outbreak under favourable conditions
especially in summer months. Grown up caterpillars eat the entire
laminar portion of the leaf leaving the mid ribs.
Some times, balls of excreta will be seen as a layer on the ground
around the coconut palm basin.
In severe outbreak, the pest invades nuts and even leaf stalks. Drying
of entire foliage, drooping of leaves and bunches, falling of buttons
and nuts are ultimate symptoms of pest attack.

Damage to intercrops
The pest was observed causing damage even to intercrops such as banana/
cocoa and surrounding hedge plants like agave after drying of coconut
crop. In such cases, falling of buttons and nuts, drying of total
foliage leads to severe yield loses and spathe emergence will be
delayed till the palm recovers.
The total life cycle of the pest is completed in about two months.
Caterpillar is yellowish green in colour, a series of tubercles are
present on the dorsal and lateral sides of the caterpillar. After
completion of larval period all the caterpillars congregate together
and pupate in the corners of the leaflets or crown region.

Light trap studies
There is a natural phenomenon of getting attracted to light source to
certain types of lepidopteran insects (moths), which can be exploited
for pest monitoring, mass trapping and destruction.
To test this phenomenon in the caterpillar, studies were conducted at
infested coconut gardens of Sakinetipalli village with electric bulbs,
gas lights and emergency lights.
Observations were recorded throughout the night (5 pm to 5 am). A
large number of moths (about 100 to 1,200 per light) were being
attracted in a night. These attracted moths were trapped and killed by
placing a big pan with water and sticky paper under the bulb.
Major breakthrough
This is a major break through in the slug caterpillar management and
it can be used as tool for monitoring and also for mass trapping and
destruction of the pests.

Dr. A.Sujatha
Dr. N.Emmanuel
&. Dr. B.Gautham
Andhra Pradesh
Horticultural University
Ambajipeta
Andhra Pradesh

Wednesday, August 12, 2009

Management of leaf folder in rice

Yield loss is from 30-80 per cent
Insect pests damage rice crop at different stages of crop growth.
Among other pests leaf feeding insect pests are of major importance because of their ability to defoliate or to remove the chlorophyll content of the leaves leading to considerable reduction in yield.
Rice leaf folder, Cnaphalocrosis medinalis was considered as pests of minor importance have increased in abundance in late 1980’s and have become major pests in many parts of India including Tamil Nadu.
The yield loss is from 30-80 per cent due to leaf folder epidemic situation.

Symptoms of damage
Longitudinal folding of leaves and scrapping of green tissues. Eventually leaves become white and dry.
During severe infestation the whole field exhibits scorched appearance. Identification of insect pest
Egg is flat, oval in shape and yellowish white in colour. Larva is pale green, transparent and actively moving caterpillar. Adult is orange brown moth with many dark wavy lines in the centre and dark band on the margins of wings.

Management strategie
— Release Trichogramma chilonis thrice at 1,00,000/ha (if moth activity is noticed) and spray Bacillus thuringiensis at 1.0 kg/ha when the leaf folder crosses tolerance level.
— Avoid use of excess nitrogen
— Set up light traps to attract moth
Spray any one of the following: Fenitrothion 50 EC 1000 ml/ha (or) Phosalone 35 EC 1500 ml/ha (or) Quinalphos 25 EC 1000 ml/ha (or) Dichlorvos 76 WSC 250 ml/ha (or) Chlorpyriphos 20 EC 1250 ml/ha Carbaryl 50 WP 1.0 kg/ha (or) Fenthion 100 EC 500 ml/ha Profenophos 50 EC 1000 ml/ha (or) Neem seed kernel extract 5 per cent 25 kg/ha.

L. Allwin V. Radhakrishnan & C. Harisudan Tamil Nadu Agricultural University, Coimbatore

Wednesday, July 29, 2009

An excellent method to ward off wild animals from crops

An excellent method to ward off wild animals from crops

M.J. PRABU

The eggs’ pungent odour repels herbivorous animals from entering the field

— Photo: M. Balaji

Perennial problem: A wild bison has strayed into a banana field situated near the edge of a forest.

FARMERS IN India and abroad face serious threats from pests, natural calamities, thefts, damages by animals and other types of crop losses, resulting in lower yields.

Most often, none of the steps taken to counter the problems are foolproof.

“More pronounced damage gets caused by wild animals in lands adjacent to forest areas during summer, due to food and water shortage in the forests.

“Farmers and officials plead helplessness in solving this perennial problem, and say they only try to drive the wild animals away manually,” says Dr. Narahari, former Professor and Head, Poultry Science, Tamil Nadu Veterinary and Animal Sciences University, Chennai.

New methods

Though scientists constantly search for new methods of crop management, to reduce losses to farmers, the damage by wild animals such as deer, elephants, and wild boars continue.

“For example, in North America, particularly the U.S., crop damage due to wild deer is a common occurrence. Large herds of these animals frequently cross the roads during nights, causing many accidents and enter into human habitations and damage home gardens and field crops.

Hatchery waste

“Though farmers tried several methods, the problem continued. Interestingly, some workers in chick hatcheries noticed that the deer herds do not come near the places where they dispose their hatchery waste; which contains a lot of unhatched eggs,” says Dr. Narahari.

By observing this, some hatchery workers started spraying the egg contents mixed with water, on their home gardens and noticed that the deer do not come near the plants (sprayed with egg contents), probably due to the pungent odour emitted by the raw egg contents when exposed to the air.

Successful results

After noticing these successful results, agricultural scientists started refining this technique for larger application and succeeded in minimising the attacks of the animals on field crops

“In India we read reports that wild animal such as elephants and bison venturing into the fields, destroying the crops.

“If we adopt this idea, we may be able to protect our crops from damage. It will be worthwhile for our farmers to try this method and give us the feedback. As of now I don’t think any person in India is practising this,” he says.

Several problems

With today’s agriculture facing many problems, a good crop yield with minimal expenditure is the need of the hour, and farmers who want to try this method need not spend much.

Giving details on how to use this technology Dr, Narahari explains:

Use egg contents (both albumen and yolk), preferably from broken, damaged, old, liquefied, unhatched or even ordinary table eggs, (unhatched eggs from hatcheries are not only cheaper, but also emit more pungent smell, disliked by herbivorous animals.)

Fertilizer

Break open the egg shell and pour the contents into a bucket or barrel. Mix yolk and albumen together. Hand-crush the leftover shells and use as fertilizer. For each 100ml (2 eggs contents), add 10 litres of water and mix well. Spray over crops, trees etc. using a hand or mechanical sprayer, similar to one used for spraying pesticides.

Since eggs are safe, the dose can be doubled to 200ml/10litre of water, if animals get accustomed to the smell.

Intense spray

Similarly, use double strength solution or more intense spraying on the edges of the crops for about 10 feet on all the four sides of the field or on the side (forest side) from which animals enter the field, to repel them from a distance.

The pungent odour generated by the eggs, will repel the herbivorous animals from entering into the field.

How long will the smell remain?

“The pungent smell remains for about a month; but during rains, the water will wash away the egg contents over the crop. Even snow will remove the smell quickly in about two weeks.”

Eco-friendly

Hence egg spraying has to be repeated after a rain or when the pungent smell is lost. This egg spray protects the crops from animals; without having any harmful side effects and is eco-friendly.

Moreover, the spill-over of highly nutritious egg liquid on the soil, makes it more fertile.

For more information, contact Dr. D. Narahari, former Professor and Head, Poultry Science, Tamil Nadu Veterinary and Animal sciences University, Chennai, email: narahari.devareddy@gmail.com, mobile: 94448-10639.

Brown Plant hopper in Rice ( text from http://www.ncipm.org.in )

Identification
The adults are brown in colour with brown eyes and measures 3.5- 4.5mm
in length. Their legs are light brown and the tarsal claws are black.
The wings are hyaline with brown markings and dark veins. The nymphs
are brownish- black in colour and have greyish- blue eyes.

Management

Closer spacing of 15x10cm creates favourable microclimate in
field for rapid development of hopper population. Hence, a spacing of
20x15cm should be followed.

Alternate drying and wetting the field during peak infestation
and draining out the standing water from the field 2-3 times checks
the population of the hopper to a large extent.

Alley 30cm wide after every 3 meters of rice planting provides
proper aeration to the crop, which ultimately restricts the
multiplication of the pest. Making of alleys also helps in
insecticidal spraying as applicator can move freely in the field.

Spray at ETL of 5-10 insects/ hill. 625g of carbaryl 50WP or
625ml of fenthion 1000EC or 2.0 litres of quinalphos 25EC or 1 litre
of chlorpyriphos 20EC in 250 litres of water per ha. Repeat
application if hopper population persists beyond a week after
application. While spraying nozzle should be directed at the basal
portion of the plants.

Monday, July 27, 2009

Tobacco leaf-eating caterpillar ( text from http://www.indiaagronet.com)

Tobacco leaf-eating caterpillar

Spodoptera litura F.
Family:- Noctuide
Order:- Lepidoptera

Marks of identification: - The moths are medium sized and stout bodied, with front wings pale Grey to dark brown in colour having wavy marking and whitish hind wings. The caterpillars are pale greenish-brown and smooth, with dark markings and a prothoracic plate and are about 37.5mm long when full-grown.

Nature of damage; - The caterpillars, when young, feed gregarously on tender leaves and juicy stems at become isolated at the later stages of growth.

Host plants: - Tobacco, peas, brinjal, castor, banana, agathi are the main hosts.

Life history; - Numerous eggs are laid in masses covered with brown hairs on tender leaves and they hatch in a period of four to five days. The caterpillars, which are darkish in appearance, on hatching start feeding on the soft green layers of leaves gregariously during the night, both in seedbeds and planted fields. They become pupate in rough earthen cocoons. Their pupal period lasts from nine to fourteen days and the total period of their lifecycle is 30 to 40 days.

Control measures; - Preventive measures such as collection and destruction of eggs masses and caterpillars and thorough ploughing after the harvest of the crop to expose pupae may be launched with a fair degree of effectiveness. At the early stage of infestation dusting with 10% carbayl at 20-25 kg/ha controls the pest satisfactory. When the caterpillars are about to pupate it is better to collect and destroy them on large scale.

Leaf spot in Turmeric - Text from http://www.spices.res.in

Leaf spot
The disease is caused by Colletotrichum capsici.

Symptoms
* It appears as brown spots of various sizes on the upper surface
of the young leaves.The spots are irregular in shape, whitish or
grayish in the centre.
* Later two or more spots may coalesce and form an irregular patch
covering almost the whole leaf.
* The affected leaves eventually dry up.
* The rhizomes do not develop well.

Management
* The disease can be controlled by spraying the plants with zineb
0.3% or Bordeaux mixture 1%.

Rhizome Rot ( Phytium graminicolum) in Turmeric - Text from http://www.spices.res.in

From these photographs, you can see various stages of Rhizome rot in Turmeric and ultimate damage too.

Symptoms
  • Starting from the margins the leaves get dried up, collar region of pseudostem becomes soft and water-soaked and plants collapse.
  • The rhizomes decay as a result of the attack of the fungus.

Control

  • Seed Material should be selected from disease free areas.
  • Avoid water Stagnation in the field. Light soil may be preferred and drainage facility to be ensured.
  • Grow tolerant varieties like Suguna and Sudarshan.
  • Crop rotation to be followed.
  • Deep ploughing to be given in Summer. Planting to be done in Ridge and furrow method.
  • Remove diseased plants and the soil around plants to be drenced with Mancozeb (3gm/lit) or 3gm Ridomil M.Z.
  • Spray on the crop Mancozeb (2.5g/lit) or Carbendazim (1g/lit) +1ml Sandovit.
  • Seed treatment is a must. Keep Rhizomes in 3gm Mancozeb or 1gm Carbendazim or 3gm Ridomil M.Z or 2.5 gm Metalaxyl mixed in one litre of water solution for one hour and shade dry before planting.



Thursday, July 23, 2009

Control of leaf miner menace in watermelon

Control of leaf miner menace in watermelon

Watermelon crop is attacked by many insect pests, of which leaf miner, assumes significance as it causes greater damage.

The larvae feed on the leaves by mining into them. Smaller leaves with limited feeding space are characterised by a secondary blotch.

Damage caused by a single larva is minimal; however, when the population is heavy they are capable of destroying more leaves and affect the plant growth.

Larvae are easily visible. Yellow and white to brown tunnels or blotches are noticed between the upper and lower surface of leaves. These tunnels spread all over the leaf making loops. Severely affected leaves curl, turn brown and die.

Pest biology

Eggs are oval in shape and creamy white in colour and are laid singly in punctures on the epidermis of the leaf. Entire larval period lasts for 7-9 days.

Pupae are yellowish brown in colour and distinctly segmented. Pupae are oval shaped with narrow ends. Adults are small grey coloured flies with black and yellow markings and live for about 10-20 days depending on the environmental conditions.

Management

— Collect and destroy damaged leaves along with larvae.

— Maintain the field and bunds free from weeds.

— Install yellow sticky traps to attract and kill the adults. These should be placed in and around the field at about 10 cm above the foliage. Replace the trap at least once a week.

— Avoid water stress in irrigated crop. Set up light traps to monitor and attract the leaf miner moths.

— Dusting leaves with phosalone 4D at 25 kg/ha or Carbaryl 10D at 25 kg/ha will be effective.

V. Radhakrishnan

& K. Ramaraju

Department of Agricultural Entomology

Tamil Nadu Agricultural University, Coimbatore

Thursday, July 16, 2009

Managing scale insect menace in ginger

Ginger is a subtropical shade loving plant.

The economic part of the plant namely the underground rhizome is often
attacked by scale insect, Aspidiella hartii, both in field and in
storage condition.
The minute crawling nymphs infest near the growing buds and suck the
sap. It results in shrivelling and drying of the rhizomes. The plants
are devitalized and get withered. The rhizomes fail to germinate.

Pest biology
The adult scale insect is circular in shape, light brownish to grey in
colour and about 1mm in diameter.
It reproduces without fertilization laying its young ones directly.
About one hundred nymphs are laid by a single female. The life span is
around one month. The insect multiplies rapidly on stored ginger.
Selection of healthy rhizomes free from scale infestation prevents the
insect spreading to new areas. Avoid water stagnation in the field.
Severely infested rhizomes are to be discarded before storage of
rhizomes.
Soak the rhizome seeds in 0.075 per cent quinalphos for 20-30 minutes
before storing and sowing. Drench the soil with a systemic insecticide
such as dimethoate 30 EC at 2ml/lit of water.

Rhizome treatment
To ensure seed material free from scale infestation, the rhizomes must
be treated with 0.05 per cent phosalone, methamidophos, dichlorvos or
monocrotophos.
The treated rhizomes must be kept at least for a week before planting
to get the maximum effect of the toxicants.
The scale infested rhizomes are to be dipped in the insecticidal
solution for 15 minutes, air dried and can be stored on sand.

Storing method
Storing of rhizomes in dried leaves of Strychnos nux-vomica also helps
in keeping the rhizomes free of scale infestation.
Two species of parasitic wasps and one species of a predatory mite
keep the population of ginger scale insect under biological control.

J. JAYARAJ & M. ANANTHAN

HORTICULTURAL RESEARCH STATION, THADIYANKUDISAI PERUMPARAI, DINDIGUL,

Thursday, July 9, 2009

Papaya mealy bug – a new threat to sericulture

Papaya mealy bug – a new threat to sericulture

Papaya mealy bug is a polyphagous sucking insect pest and has been recorded on more than sixty host plants in India.

But its serious attack was recorded only in a few economically important crops such as papaya, mango, pomegranate, citrus, beans, tomato, potato, pepper and cotton. In other plants it exists as a minor pest.

However sudden outbreak of any minor pest is common owing to various reasons.

The recent trend in the population built-up of papaya mealy bug on mulberry, the sole food plant of silkworm, indicates its emerging pest status especially in South India where mulberry is cultivated intensively.

Infestation

Papaya mealy bug infestation is typically observed as clusters of cotton like masses on tender stem and veins of mulberry leaves as the insect secretes a white waxy coat over its body.

The adult female lays 100-600 eggs which hatch into nymphs in about ten days. The nymphs crawl actively to search for feeding sites and settle in clusters on leaves and stems.

One generation

The pest completes one generation in a month. The symptoms appear on the leaves as chlorosis (yellowing), deformation and premature drop. Hence, feeding with papaya mealy bug infested mulberry leaves adversely affects the growth of silkworm and silk production.

Cultural method

Planting of highly susceptible host plants such as papaya or hibiscus in the vicinity of mulberry garden should be avoided.

Plugging of the infested twigs and leaves and their burning during early stage of infestation is the best method of eradication of the pest.

Indiscriminate use of insecticides in mulberry fields should also be avoided as they induce resistance in the pests and destroy its natural enemy population.

Biological control

Release of Cryptolaemus montrouzieri, an effective predatory ladybird beetle at 125 adults per acre twice a year at the interval of six months keeps the pest population suppressed.

Spraying dimethoate (0.05 per cent) controls the pest effectively. Leaves can be fed to silkworms 15 days after spraying the insecticide.

N.Sakthivel

Regional Sericultural

Research Station

Central Silk Board, Salem

Tamil Nadu: 636 003

Saturday, June 27, 2009

Integrated Pest Management in Rice

Area coverage of rice is highest in West Bengal (in comparison to any
other crops) and naturally a considerable amount of pesticide is used
to protect the crop from insect and diseases. It is more so for the
boro (winter season) rice which provides higher productivity. In most
of the cases pesticide application is ritualistic and results in
pesticide resistance or pests, environmental pollution and residue
problems. Integrated approach of pest is expected to spell definite
positive results considering the area coverage of rice in the state.
At the same time, complete switch off of pesticide application may not
sound promising in near future. An integrated approach to cope up with
the insect pest problem in rice is, hence, a need of the hour.

1.Selection of resistance varieties
2.Seed treatment with Carbendazim 50 WP (2 g/kg of seed ) and/or
Streptomycin (1g/10 L of water or 1g/6.5 kg of seed)
3.Application of Carbofuran 3G (4.5 kg a.i./bigha) or Phorate 10G (1.6
kg a.i./bigha) in the nursery 7-8 days before sowing.
4.Timely transplanting in larger area at a time.
5.Split application of nitrogen, application of micronutrient.
6.Green manuring; application of organic manure.
7.Removal of weeds from the main field and bunds (bio-physical
boundary of the field).
8.Removal of seedling tip before transplanting.
9.Pheromone traps against stem borer.
10.Gap of 2 rows after each 8-10 rows of seedlings to control Brown
Plant Hopper.
11.Application of neem based pesticides like neem oil/extract.
12.Avoiding pesticide application during the early growth stage of the
plant.
13.Recommended chemicals in extreme cases –
Rice stem borer -
Chloropyriphos (1.5 ml/L of water)
Cartap hydrochloride (1 ml/L of water)
BPH-
Imidachlorpid (1 ml/7.5 L of water)
Thiomethaxom (1 ml/L of water)
Ear cutting Caterpillar -
Profenophos (1.5 ml/L of water)
Cartap hydrochloride (1 ml/L of water)
Blast-
Propiconazole (1 ml/L of water)
Tricyclazole (0.6 g/L of water)
Sheath Blight-
Validamycin (2.5 ml/L of water)
Hexaconazole (2 ml/L of water)

It has been found that the following varieties have considerable
resistance against specific pests.

Rice stem borer - Ratna, Shashyashree, Bikash
BPH - Chaitanya, Pratibha, Manas Sarovar, Reshmi
Blast- Rasi, IR-36, Parijat, Shashyashree
Sheath blight- Pankaj, Swarna, Manas Sarovar

Wednesday, April 8, 2009

Monday, April 6, 2009

Role of seed treatment in insect pest management

Role of seed treatment in insect pest management

Seed treatment is an application of chemicals to the seeds either at
the time of sowing or before sowing which is an alternative to
traditional foliar or soil treatment.

Efficient function
Application of insecticides to seeds before or at the time of sowing
offers the most effective means of protecting the germinating seed or
seedling.
The chemical insecticide is absorbed by the plant tissue and
transported in the sap through the entire plant through the vascular
system, right up to the top leaf.

Natural enemies
The pest ingests the chemical compounds along with the plant juice
that is lethal for them.
Natural enemy population such as coccinellids, spiders and chrysoperla
remain unharmed.
The efficacy of seed treatment depends upon a mulltitude of
interacting factors such as seed type, chemical formulation,
compatibility of materials, adjuvants and species of insects etc. Seed
treatment with lower doses of imidacloprid, at 5g/kg seed was found
effective in controlling jassids up to 60 days after emergence of crop
and higher seed cotton yield.

Treatment method
Treatment with marshal 25 DS at 80g/kg of seeds has recorded least
population of sucking pests and resulted in higher yield of sunflower.
Acetamiprid 20 SP at dosage of 25g a i/kg of seed protects cotton crop
up to 35 days against pests.
Seed treatment of sorghum with imidacloprid 70 WS at 15g/kg seeds or
thiamethoxam 70 WS at 10g/kg followed by foliar sprays after 30 days
with imidacloprid 17.8 SL at 0.01 per cent or thiamethoxam 25 WG at
0.01 per cent were found highly effective for the management of shoot
fly and stem borer.

Sharanabasappa
D. Satish
& Satyanarayan

Regional Agricultural Research Station, Raichur
& Department of Genetics and Plant breeding
College of Agriculture
UAS Dharwad







Saturday, February 14, 2009

Control of late blight disease in tomato

Control of late blight disease in tomato
Late blight, caused by a fungus Phytophthora infestans, is one of the most devastating diseases of potato and tomato worldwide.
It first appears on the leaves and stems, and later on the fruits. Symptoms appear on leaves as pale green, water-soaked spots, often beginning at leaf tips or edges. The circular or irregular leaf lesions are often surrounded by a pale yellowish-gree n border that merges with healthy tissue. White mould growth
Lesions enlarge rapidly and turn dark brown to purplish-black. During periods of high humidity and leaf wetness, a cottony, white mould growth is usually visible on the lower leaf surface at the edges of lesions. In dry weather, infected leaf tissues quickly dry up and the white mould growth disappears.
Infected areas on stems appear brown to black and entire stem may be killed in a short time when moist weather persists.Fruit lesions
The fungus produces grey-green water-soaked spots which enlarge, coalesce, and darken, resulting in large, firm, brown, leathery-appearing lesions on fruits.
Cool nights and warm days with moist weather, which prevail during October-November, are the best conditions for development of the disease. Rain, fog or heavy dew are also ideal.Some management tips
— The disease is soil borne and can be managed by using integrated approaches to crop production and protection.
— Plant only healthy tomato transplants. Check to make sure plants are free of dark lesions on leaves or stems.
— Planting at recommended space (100 x 60cm), raising the crop in raised beds, removing infected fruits and staking of plants to avoid contact of fruits with soil for good air circulation is advisable.
— Spray at regular intervals. Begin chemical control programs before symptoms appear.
Copper hydroxoide(2g/lit) chlorothalonil (2g/liter) and mancozeb (2.5 g/liter) fungicides are the standard protectants used for control. They are usually applied every seven to ten days for best protection.
P.Chowdappa
Girija Ganeshan
& N.Ramachandran
Division of Plant Pathology
Indian Institute of
Horticultural Research
Bangalore

Thursday, January 29, 2009

Management of downy mildew in sunflower

Management of downy mildew in sunflower
Sunflower crop is among the top five commercial oilseed crops grown all over India.
Its cultivation is mainly hindered by diseases and pests. Among the diseases downy mildew is a serious obstacle in sunflower cultivation due to its systemic nature of infection.
Typical symptoms occur in seedling stage. Infested seedlings die, but those that survive produce stunted plants with erect, platform heads with no flowers. Drought stress
If any flowers are produced they remain sterile and bear no seeds. The infested plants serve to perpetuate the fungus in the soil and are more prone to drought stress and lodging.
The disease is initiated by soil borne dormant structures called oospores or infected seeds.
Oospores germinate during spring in wet soils. They can survive in the soil for five to 10 years.
Cool, water-saturated soil during this period greatly favours the infection spread.
Plants become increasingly resistant to infection with age, so systemic infections occurs over a short period (two to three weeks) after germination.
Irrigation water running through an infested field also may carry mildew spores into a previously disease-free field. Management
— Plant high quality certified seeds free from downy mildew pathogen.
— Practise a five-year or longer crop rotation between sunflower crops with non-hosts such as corn and small grains.
— Eliminate weeds that can serve as alternate hosts of downy mildew.
— Avoid reuse of irrigation water from sunflower fields and provide adequate but not excessive irrigation, especially early in the season.
— Seed treatment with metalaxyl 6gm/kg seed will reduce the infection during the seedling stage. Spraying of rydomil MZ 3gm/lit or metalaxyl 3gm/lit water helps in controlling foliar infection.
— Using resistant varieties. is a good practice.
Mallikarjun Y, Kenganal, Hemavati, Ranebennur & Byadgi, A. S.
Department of Plant Pathology
University of Agricultural Sciences,
Dharwad, Karnataka

Wednesday, January 7, 2009

Mealy bug — a new threat to cotton cultivation

Mealy bug — a new threat to cotton cultivation
Cotton crops in Punjab, Rajasthan, Maharashtra, Andhra Pradesh, Gujarat and Tamil Nadu are being seriously infested with mealy bugs during the last 2-3 cropping seasons.
In Tamil Nadu the pest has been observed in Salem, Coimbatore, Perambalur, Erode, and Virudhunagar districts.
Mealy bugs are small, soft bodied sucking insects which suck the sap from the stem, twigs, leaves, flower buds and young bolls. Sooty mould
A sugary liquid secreted by these insects falls on the leaves and serves as a medium for the growth of sooty mould, a fungus that reduces photosynthetic ability of the plant.
Adult female lays 400-600 eggs in a thin bag called ovisac and within 3-9 days young mealy bugs called crawlers emerge from the ovisac.
The crawlers actively spread through various means and settle down in 25-30 days.
The pest causes premature leaf drop, dieback and death of plants if unchecked.
Serious attack of the pest results in bunchy growth, plants remain stunted and produce fewer bolls. Heavy clustering of mealy bugs can be seen on lower surface of leaves giving the appearance of a thick mat with waxy secretion.
The honeydew excreted by the mealy bugs attracts ants which help in spreading of the pest and provide protection from predators and parasites.Management
—Field borders should be free from weeds.
—Crop residues with infestation should be removed and burnt.
—Plough the infested fields to expose the immature stages in the soil to the biotic and abiotic factors.
—Discourage growing alternate host plants such as hibiscus, okra, custard apple, guava in nearby cotton fields.
— Encourage cowpea as border crop on bunds and irrigation channels to enhance the multiplication of predatory insects.
— Ant fences should be treated with chlorpyriphos 20 EC at 2.5 ml/lit through drenching (or) by application of malathion dust 5 per cent at 25 Kg/ha .
B. Dhara Jothi &
N. Gopalakrishnan
Central Institute for Cotton Research
Regional Station
Coimbatore, Tamil Nadu Mealy bug — a new threat to cotton cultivation
Cotton crops in Punjab, Rajasthan, Maharashtra, Andhra Pradesh, Gujarat and Tamil Nadu are being seriously infested with mealy bugs during the last 2-3 cropping seasons.
In Tamil Nadu the pest has been observed in Salem, Coimbatore, Perambalur, Erode, and Virudhunagar districts.
Mealy bugs are small, soft bodied sucking insects which suck the sap from the stem, twigs, leaves, flower buds and young bolls. Sooty mould
A sugary liquid secreted by these insects falls on the leaves and serves as a medium for the growth of sooty mould, a fungus that reduces photosynthetic ability of the plant.
Adult female lays 400-600 eggs in a thin bag called ovisac and within 3-9 days young mealy bugs called crawlers emerge from the ovisac.
The crawlers actively spread through various means and settle down in 25-30 days.
The pest causes premature leaf drop, dieback and death of plants if unchecked.
Serious attack of the pest results in bunchy growth, plants remain stunted and produce fewer bolls. Heavy clustering of mealy bugs can be seen on lower surface of leaves giving the appearance of a thick mat with waxy secretion.
The honeydew excreted by the mealy bugs attracts ants which help in spreading of the pest and provide protection from predators and parasites.Management
—Field borders should be free from weeds.
—Crop residues with infestation should be removed and burnt.
—Plough the infested fields to expose the immature stages in the soil to the biotic and abiotic factors.
—Discourage growing alternate host plants such as hibiscus, okra, custard apple, guava in nearby cotton fields.
— Encourage cowpea as border crop on bunds and irrigation channels to enhance the multiplication of predatory insects.
— Ant fences should be treated with chlorpyriphos 20 EC at 2.5 ml/lit through drenching (or) by application of malathion dust 5 per cent at 25 Kg/ha .
B. Dhara Jothi &
N. Gopalakrishnan
Central Institute for Cotton Research
Regional Station
Coimbatore, Tamil Nadu