DEPARTMENT OF ENTOMOLOGY

ALLAHABAD SCHOOL OF AGRICULTURE

SAM HIGGINBOTTOM INSTITUTE OF AGRICULTURE TECHNOLOGY &

SCIENCES

[Formerly-Allahabad Agricultural Institute]

(Deemed-to-be-University)

ALLAHABAD- 211007, U.P., INDIA

SUBMMITED BY,

RAKESH KR

I.D. NO. 15MSENT014

SUBMITTED TO,

DEPARTMENT OF PLANT PROTECTION

The entire “head” is called a garlic bulb, while each segment is called a clove. There are about 10-20 cloves in a single bulb, give or take.

We now know that most of the health effects are caused by one of the sulfur compounds formed when a garlic clove is chopped, crushed or chewed.

This compound is known as allicin, and is also responsible for the distinct garlic smell.

Allicin enters the body from the digestive tract and travels all over the body, where it exerts its potent biological effects.

Onion Maggot

Thrips

Red spider mite

SYSTEMETIC CLASSIFICATION

Kingdom :- Animalia

Phylum :-Arthropoda

Class :- Insecta

Order :-Diptera

Family :-Anthomyiidea

Genus :-Delia

Species :-antiqua

IDENTIFICATION

Adult - small grey bristly fly, 6 mm long, slightly smaller than a housefly.

Egg - white and elongated, 1-1.5 mm.

Larva - white legless maggots, pair of black mouth hooks at tapered end, up to 8 mm long.

Pupa - oval, dark brown, 6 mm long, resembles wheat grain.

Fig:- Egg Fig:- Larva

Fig:- PupaFig:- Adult

DISTRIBUTION-The onion fly is found in North America, Western Europe, Russia, Central Asia, China, Japan, and Korea.

HOST PLANT- Garlic, onion, shallots and leeks; prefers onions.

NATURE AND DAMAGE-

The maggots feed on seedlings, transplants and bulbs. Infested plants wilt and turn pale green to yellow.

First generation maggots in the spring cause the most damage.

Young plants are more susceptible to attack and can be killed, established plants are damaged but not usually killed.

Feeding damage causes misshapen bulbs and allows the entry other species of maggots and decay organisms

Fig:- damage by maggot

LIFE CYCLE:- Eggs hatch in 2 to 5 days, and most newly hatched

larvae move below the soil surface and burrow into the basal plate of the onion plant or feed on the roots.

Any injury site on the bulb facilitates larval entry, and larvae will feed on developing onion bulbs for 2 to 3 weeks.

Upon reaching maturity, larvae leave the onion bulb and pupate in the surrounding soil. Offspring of the first and second-generation adults will remain in this stage for 2 to 4 weeks before emerging as adults.

The onion maggot life cycle lasts from 37 to more than 60 days.

The first-generation adults emerge from pupae around mid-May in the northeastern US, with peak flights occurring about 2 weeks later.

Adults can survive for 2-4 weeks and may lay hundreds of eggs, beginning approximately 7 to 10 days after emergence.

CULTURAL CONTROL:- Harvest all bulbs, remove culls, volunteer crops and crop

residues from the field to reduce overwintering populations. Avoid planting in soils that are high in undercomposed

organic matter. Do not plant allium crops (onions, garlic, leek) in the same

location for a minimum of three years. This will also help to reduce potential disease problems.

BIOLOGICAL CONTROL:- Parasitic wasps, predatory flies, ground beetles and

pathogenic fungi help reduce onion maggot populations.

CHEMICAL CONTROL:-

The only chemical registered for onion maggot control in garlic is Lorsban (chlorpyrifos).

Sprays are most effective when applied in the morning (8 to 10 a.m.) or early evening (6 to 9 p.m.).

Spraying of weeds immediately surrounding fields will give additional protection against onion maggot.

SYSTEMETIC CLASSIFICATION

Kingdom :- Animalia

Phylum :-Arthropoda

Class :- Insecta

Order :-Thysanoptera

Family :-Thripidae

Genus :-Thrips

Species :- tabaci

These are minute organisms. The adult measures only 1 mm in length.

The body of adult is yellowish-brown in colour, with slender thorax and abdomen. Abdomen tapers posterior.

Female bears full wings but in male the wings are extremely reduced or absent.

Wings are narrow, consisting of stiff portion bearing a fringe of hairs.

The legs are adapted for running. Each leg terminates in two jointed tarsus and a

peculiar vesicle or bladder without claws.

Adueggs

Fig:- nymph

Fig:- adult

Fig:- Egg

Fig:- pupa

DISTRIBUTION: -Severe damage to various crops has been reported in Africa, Asia, Europe, North and South America, and Australasia

(Mound 1997, Boateng et al. 2014).

HOST PLANT- Garlic, onion, shallots and leeks, cauliflower, cabbage, cucumber, squash, melon, tomato, turnip, bean, beets, cotton.

NATURE AND DAMAGE:- The adult thrips and their nymphs lacerate the surface tissues of the foliage.

They puncture the leaves and stem of the host plant and suck the exuding sap.

In the initial phase of attack by this pest the leaves show spotted appearance and later on whitish blotches appears due to drainage of leave sap.

The tip of the leaf gets distorted and falls.

Fig :- Damaged on leaves with silvery patches Fig :- Thrips on neck region plant

LIFE CYCLE:-

Although, the pest remains active throughout the year, intense breeding generally occurs between November and May, which is the main period of onion and garlic cultivation.

Adult female lives for two to four weeks. During this span it produces 50 to 60 eggs at the rate of 4-6 eggs per day.

The eggs are laid singly and are inserted in the leaves of host plant through the slit made by ovipositors of the female.

The eggs are white and bean shaped.

Nymph hatches out from the eggs within 4-9 days.Nymphal period lasts for4-6 days during which they pass through four instars

Prepupal stage lasts for one to two days and pupal stage for two to four days, after which adult emerges out.

Life cycle is completed in 11 to 21 days.

CULTURAL CONTROL:- Remove cull piles, plant debris and volunteer plants

from the field. Delay controlling weedy areas until they begin to dry

out. Controlling weedy areas after plant emergence may

increase thrips problems. Sprinkler irrigation can help suppress thrips. Avoid

planting near crops that harbor thrips such as alfalfa, wheat or clover.

CHEMICAL CONTROL: – Malathion, Matador, Silencer, Delegate, Success,

Entrust, Movento, Exirel, Agri-Mek are registered for the control of thrips.

SYSTEMETIC POSITION:-

Kingdom :- Animalia

Phylum :-Arthropoda

Class :- Arachnida

Order :-Trombidiformes

Family :-Tetranychidea

Genus :-Tetranychus

Species :- cinnabarinus

IDENTIFICATION:-

Eggs - laid singly on the underside of the leaf or attached to the silken webs spun by the adults

Larvae - pinkish, slightly larger than the egg and have three pairs of legs

Nymphs - reddish or greenish and having 4 pairs of legs

Adult - females are reddish and more or less elliptical in shape

DISTRIBUTION:- It has been recorded from most countries in Europe, Asia, Africa, Australasia, the Pacific and Caribbean islands, North, Central and South America.

Bolland et al. (1998).

HOST:- Onion, Garlic, Okra, Groundnut, Tea, Beatroot, Pepper.

NATURE AND DAMAGE:-

Adults and nymphs feed primarily on the undersides of the leaves.

The upper surface of the leaves becomes stippled with little dots that are the feeding punctures.

The mites tend to feed in “pockets” often near the midrib and veins.

Silk webbing produced by these mites is usually visible.

The leaves eventually become bleached and discolored and may fall off.

Fig :- Silk webbing on the flowersFig:- Silk webbing on the leaves

LIFE CYCLE:-

The development of the mite is rapid, particularly at high temperatures.

At 30-32°C, which is the optimum temperature for development, the egg stage lasts 3-5 days, the larval/nymphal stages 4-5 days, and with a pre-oviposition period of 1-2 days, the total life cycle takes only 8-12 days.

Each female can lay an average of 90-110 eggs during a lifetime of about 30 days, therefore numbers of mites can increase very rapidly during the summer, or under glass or plastic.

The most successful examples of biological control. The predator used most often has been the phytoseiid mite Phytoseiulus persimilis.

Avoid planting successive onion or garlic crops

Apply wettable Sulfur 0.3% + dimethoate(0.03%) or 0.5% sulfur or dicofol 2ml/l (0.05%) or fenaziquin 2ml/l(Magister) as pre-sowing and post- sowing treatments

Through water spray also washes off the mites from the plant

Srinivas, P.S. R.P. Singh and K.E. Lawande. 2007. Integrated Pest and Disease Management in Onion and Garlic. Technical Bulletin No.17. ICAR-Directorate of Onion and Garlic Researxch, Pune, Maharashtra, pp.34.

Srinivas, P.S. and Lawande. 2006. Maize barriers as a cultural method for manipulation of thrips in onion. The Indian Journal of Agricultural Sciences, 76(3):167-71.

Sankar, V., Thangasamy, A and Jai Gopal. 2014. Improved cultivation practices for onion. TehnicalBulletin No. 21. ICAR-Directorate of Onion and Garlic Researxch, Pune, Maharashtra.pp.23.