Cultural Practices in Pest Management-1

Definition

 

Cultural control is the deliberate manipulation of the environment to make it less favourable for pests by disrupting their reproductive cycles, eliminating their food, or by making it more favourable for their natural enemies. This is a prophylactic method of pest control.

 

Scope to Use

 

It can rarely be used as tactical means of control except perhaps in stored product systems where spot check fumigation can be achieved by modification of the storage environment. On its own it is unlikely to reduce pest infestation to desirable levels, but within the framework of an insect pest management system it can be used to reduce overall levels of infestation to below economic damage thresholds. Cultural control represents an important component in the development of a coherent, holistic approach to pest management and thus demands a greater attention than is currently given.

 

List of Cultural Practices:

 

1. Sanitation/Destruction of residues
2. Destruction of alternate hosts and volunteer plants
3. Variation in time of planting and harvesting
4. Crop rotation to avoid building up of pests
5. Tillage practices
6. Habitat diversification/Cropping systems/Intercropping
7. Plant density
8. Trap crops/Trap logs
9. Water management
10. Fertilization and
11. Miscellaneous practices

 

1. Sanitation/Destruction of Residues

 

• This practice involves removal or destruction of breeding refuges or overwintering sites of pests. Removal of fallen fruits from orchards and destruction of tree pruning are useful in reducing the insect and disease pests which over winter in these materials.

• Crop residue can act as media of insects’ preservation. As for example: the continuation of the population of sweet potato weevils may be checked if the storehouses are cleared of the rotten potatoes on which they are found to be breeding.

 

2. Destruction of alternate hosts and volunteer plants

 

• There are some weeds can act the same. So such crops should immediately be eliminated and crop residues should burn out.

• Pest populations may often be effectively suppressed by destruction of their alternate plant hosts (i.e. their secondary hosts, weeds or the volunteer crop plants along the edge of crop fields).

• This technique, in effect a weed control, has been more effective against plant diseases than other pests including those spread by the insect vectors.

 

3. Variation in time of planting and harvesting

 

• Insects, which like the specific stage of plant, they cause severe destruction in those stages. The insect infestation may be prevented by shifting the plantation date from the period of activity of its pests.

• However, the effect of planting dates and harvesting dates on yield must be simultaneously taken into consideration in fixing those timings.

 

• Planting time

 

In general in the tropics, early planting at the start of the rainy season is essential if the best yields are to be obtained. As a rule, yields are markedly and progressively reduced the more delay is made in planting after the onset of the rains. Early sown crops may benefit from a reduced level of insect pest infestation although early planting is not always the most appropriate strategy to ensure reduced levels of attack.

 

• Harvesting time

 

Similarly, in crops where insect pest reach outbreak populations during a season and produce a resting stage at that end of a season it is possible that the area will act as a major source of pest inoculums during the subsequent season. This can sometimes be avoided if the crop is harvested before the insect develops its resting stage. For example: the early cutting of a second harvest of alfalfa interrupts the development of the potato leafhopper offsprings, Empoasca fabae, before any become nymphs or adults.

 

 

4.      Crop rotation to avoid building up of pests

·         Insects feeding on almost all kinds of plants are very rare. The continuation of one crop in a field obviously results in the accumulation of its pests as they are benefited with good food supply. A rotation of the crop which is not attacked by these pests will compel them either to drive off or to die for want of food and may also even encourage the increase of predators and parasites of the pests.

·         Generally crop rotation is most effective against pests with a restricted plant host range and, for insects, those with limited capability to migrate.

·         Crop rotation is one of the oldest and most effective measures for controlling plant-parasitic nematodes, soil-borne fungi and bacteria and weeds.

·         Rotation is frequently a useful pest control technique and as an important place in many IPM scheme.

·         Examples:

-          In the Imperial Valley of California, the sugar beet cyst nematode is satisfactorily managed by crop rotation program.

-          Corn rootworms in the Midwestern USA can be effectively controlled by crop rotation.

-          Crop rotations have been shown to be effective against Colorado potato beetle (Leptinotarsa decemlineata) by creating a delay in the time of crop infestation. In a rotation of potato and wheat the oviposition and first appearance of the beetle were delayed when compared with an unrotated potato field. This delay was attributed to physical and environmental barriers that slow emigration from the wheat by the overwintering adults.

-          In Europe, typical rotations involve grasses, legumes and root crops which have been used to control three insects including wireworms (Agrotis spp.)

·         Limitations of Crop Rotations:

-          Often, populations of pests other than the target pest increase on the alternate crops. Some crops used in rotation are of such low value that they contribute little to farm income.

-          Further, alternate crops may require additional farm machinery.

-          Crop rotations have become less popular as more intensive farming methods have been utilized

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 Bismark Bangali

BSC  in Agrotechnology 

 

 

 

Khulna University.