Plant Protection

Managing of protecting field from the attack of insect pests, diseases, rats etc. called plant protection. Insect pests, mites, disease, pests, and rats are the main enemies of crop. These pests destroy a considerable part of the produced crop. But the amount of destruction can be minimized by proper management.
Along with harmful insects, there are various beneficial insects too, in the crop field. They help in pollination of flowers and by eating the eggs and larvae of harmful insects. It is therefore, essential to control harmful insects by protecting the beneficial ones.

Integrated Pest Control Management

 Control of harmful insects by following certain control measures at a time, protection the beneficial insects, is called integrated pest control management. The main objective of integrated pest control management is to prevent pest invasion by decreasing the dependence on pesticides and by following with the fact that one control measures at a time. Example can be furnished with the fact that adult Hispas can be caught and killed by hand-nets or mosquito nets. The infested tops of the rice plants having larvae of the pest can be cut and buried under soil. At the same time the branches of trees can be put in the crop field whereby the birds can sit and eat the insect pests. If pests cannot be controlled in spite of taking all these measures, only then the right pesticide can be used as the last measure.

Advantages of Integrated Pest Management (IPM)

 There are many advantage keeps the environment pollution free described below
 1. Integrated pest control management keeps the environment pollution free and protects biological balance of the environment.
 2. Protects beneficial insects, mites, frogs and fish.
 3. Decreases use of pesticides.
 4. Helps crop protection with minimum expenditure.
 5. Keeps the food stuff free from the harmful influence of the pesticides.

Components of Integrated Pest Control Management 

 There are 4 components of integrated pest control management, such as_
1. Modern cultivation system
2. Mechanical control
 3. Biological control
 4. Chemical system

Modern Cultivation System 

A. Deep Ploughing of land. 

By deep ploughing the harmful insect pests, their eggs and grubs will be brought above the soil. By doing this some will be killed by sun shine and some will be eaten by birds.

B. Adopting Crop-rotation

 One particular insect pest attacks a particular crop so if a particular crop is cultivated on the same land repeatedly, pest attack will be higher in that land. But when according to production plan, different crops are cultivated in rotation in the same piece of land, then the insect and pest invasion will be minimum. For example, when transplanted Aman is cultivated after jute, invasion of insect pest will be minimum.

C. Application of Fertilizer in Balanced Doses

 The attack of insect pest and disease will be less when fertilizers are applied in balanced doses. In certain crop, when urea is applied abundantly, the top shoots and leaves of the plant become succulent. Mostly this atttracts insect pests. Again when potassium fertilizers, are applied in low quantity, the attack of diseases will be higher. So fertilizer should be applied in balanced rates.

D. Irrigation Management

 Some insects cut the young seedling beneath the soil, such as mole cricket. Mole cricket causes immense damage to jute crop. If flood irrigation is done in jute filled attacked by mole cricket, the pests can be controlled. Again draining out water from the rice field can control case worms.

E. Spacing of Seedlings

 Planting the seedling of rice thinly can control brown plant hopper.

F. Cultivation of Improved Varieties of Crop

 There are many improved varieties of crop which are resistant to diseases and pests. For example, BR-10 variety of rice is resistant to Tungru virus and blast disease. Chandina is resistant to stem borer.

Mechanical Control

 Controlling insect pests by hand or trap is called mechanical control. There are several ways of mechanical control.Some of mechanical control devices are described as under -

A. Manual Catching of Insects by Hand

 Collecting their eggs can control insect pests and larvae form the crop field by hand. The stem borers of rice and sugarcane can be controlled by this way. Again rice hispa and green leaf hoppers can be destroyed by collecting with hand nets.

B. Cutting of the Leaf Tips

 Rice hispa and leaf rollers generally attack on the top of the leaves of rice plants. In this condition their attack can be controlled by cutting the leaf tops and then by burial under soil or by burning.

C. Uprooting of Infested Plant

 The infested plant should be uprooted as soon as symptoms of attack by disease or insects are visible. By this disease and pest invasion cannot spread throughout the whole crop field.

D. Light Trap

 By setting light trap insects can be attracted towards light and can be killed. At night a pan having water mixed with kerosene or pesticide should be kept in the field. If a hurricane is kept hung on that pan many insects will be attracted towards the light of that hurricane. By this the insects will fall in the pan having kerosene or pesticide and then die. Adult stem borer, ear cutting cater pillar green plant hopper and rice bugs. Can be controlled by setting light trap.

Biological Control

 Control of harmful serious pests by using predator insects and birds is known as the biological control method: Some insects feed on other insects. These insects are called parasites or predator insects. Such as Lycosaspiders, Lady bird beetle, Mtrid bug  and parasitic insects. Some of the  predator insects are described as below:

Lycosa or Nekre Spiders
 Habitat:

 Lycosa spiders live in rice field. In most of the time, they stay in the bottom of rice plants.

Food:

 Lycosa spiders do not make nets. They attack directly on the insects. Adult spiders catch various types of insect and eat. Out of these, the moths of rice stem borer are important.

Grass Hoppers
 Habitat:

 Among the grass hoppers the grass hoppers having long proboscis are predators: These grass hoppers stay on leaves and ears of plants. These and found abundantly on the growing rice plants.

Food : 

This grass hopper eats sucking insects, stem borers and rice bugs. They catch preys at night. 

Damsel Flies
 Habitat:

 The adult damsel flies fly in spaces between the leaves of rice plants. The young ones live in water. But they climb up through the leaves to eat the young plant hoppers and leaf hoppers. 

Food: 

This fly eats different types of hoppers and leaf rollers. 

Lady Bird Beetle
Habitat:

 Lady bird beetle can be seen in all types of crops including gourd types of plants and rice field.

Food :

 Their preys are slow creeping insects. This insects eats sucking insects, stem borers and leaf roller. The young ladybird beetles can eat more insects man adult ones. 

Mirid Bug
 Habitat :

 Mirid bug lives in rice field. These can be found abundantly in rice field infested by plant hoppers and leaf hoppers.

Food :

 Mind bug lives in quest of the eggs of plant hoppers in leaf sheaths and stems of rice plants. They suck the eggs by piercing their proboscis.

Predator Birds and Frogs 

Almost all types of birds feed on insect pests of crops and thus benefit us tremendously.Among these birds the important ones are folk-tailed shrike, magpie robin, (doel) Mayna, Martin (Shalik) and Swallow (finge). Besides these, crows, eagles, owls eats rat and thus help rat control. When wooden platforms are made by the sides of the ridges of land for gourd or beans or when branches of trees are put on the field the birds can sit on those. They help in controlling insects by eating several types of harmful insects.

Frog

The frog lives in both water and soil. Insects are their main food. Frogs can be utilized for controlled insects of the crop field.

Chemical Method

 Chemical method is one of the ways of insect control in integrated pest control management. This method is  applied only when the insect  population is so large that mechanical or biological control becomes ineffective. Example can be furnished by saying that in rice field when 3 female moths or cluster of 3 eggs are found in one squaremetre or 10% dead ears are seen upto 40 days of transplantation, only then the chemical control method becomes necessary. 

Rat Control

 Rats cause damage to the houses of men and crop fields. They share human food. Rats cause 10-20% damage to the crops. Rats cut wood, clothes, furniture and crops throughout day and night. They cause damage not only to the household antics, but also spreads germs of different diseases. Rat spread plague disease. This disease, some times, becomes epidemic. There are three varieties of rats found in crop fields or houses, such as :

 1. Black rat

 2. House rat

 3. Brown rat

 The disturbances of brown rat are tremendous in Bangladesh. One pair of rat can give birth to 800-1000 number issues in only one year. 

Symptoms of Presence of Rats 

Following are the symptoms of rats 

1. Soils of Rat

 Rats dig holes in the fields and in houses and live there. Seeing the granular soils can identify presence of rats. 

2. Paths of Movement

 Marks of legs can be visible when rats move on soft soils. They move by clearing the ways.

3. Excrements

 Seeing their excrement can identify the presence of rats.

4. Smell

 Rats spread bad smell. Their presence can be identified from, this smell. 

5. Symptoms of Damage 

Rats cut, every thing crookedly. These cut-marks indicate their presence. 

6. Sound

 When rats move a kind of rustling noise can be heard, and when they, cut some thing a sound of gnawing can be heard. 

Rat Control

 Rats can be controlled in several methods, such as: 

1. Rat killing trap

 2. Poison bait

 3. Pouring water into the holes of rates

 4. Rearing cats.

1. Rat Killing Trap

 There are many types of rat traps found in markets. Rats can be killed in the traps by keeping food-baits.

2. Poison Baits

 Zinc phosphide, recumin, phostoxin can be used to make poison baits and can be kept in the rat-holes or on the ways of their movement. Rats eat Rat trap those baits and die. Lanirat is another type of poison bait. When 10 grams of poisonous things kept on the way of rats, they eat it and die.

3. Pouring Water into the Holes

 Rats can be killed when sufficient water is poured into their holes. 

4. Rearing of Cats

. Rats can be controlled by rearing cats in the house.