Overuse and non-judicious use of chemical pesticides created problems like resistance of pests to pesticides, outbreaks of previously suppressed pests, and contamination of the environment. Hence, it became paramount to solve those issues before it escalates further into a more serious one. Thus, Integrated Pest Management (IPM) evolved as a solution to these problems.
Integrated Pest management is a process used to solve the problems of pests while minimizing the adverse effects of the method on people and the environment. It aims to bring to the barest minimum, the environmental harms often associated with the effective pest control methods.
IPM is a long-term control or preventive strategy enacted on pests in an ecosystem. It prevents pests or damages emanating from the activities of pests through a combination of techniques like resistant plant varieties, manipulation of the habitat, biological control, modifying cultural practices, etc. In this method, pesticides are used as the last resort only when results from the use of IPM shows that it is necessary. However, pesticide treatments are cautiously applied to ensure that only the target organism is eliminated while reducing risks to human health, the environment, and beneficial organisms.
Prior to the 1970s, before IPM was introduced, farmers relied solely on chemicals to grow food crops because this increased production greatly, however, it was discovered that pests were getting resistant to these chemicals which necessitated the use of higher doses. This led to the production of good crops that had high amounts of chemicals in them which are dangerous to human health.
As the knowledge about the negative side-effects of pesticides overuse began to increase, IPM was introduced. This approach focuses on the integration of the biology of pests and cultural practices in the control of pests in crops.
Unfortunately, while so many IPM successes have been achieved in paper, implementation is low all over the world. Despite the enormous benefits this strategy of pest control would have on the environment as a whole and humans in particular, it has not gained ground in practice probably because the results are not as swift as pesticides.
COMPONENTS OF IPM
IPM is the combination of individual pest control methods in order to get a better result while reducing impact on the environment and humans.
This entails regular farm operations designed in such a way to either eliminate the pests or prevent them from causing economic losses. Cultural practices are numerous and not limited to the few listed below:
Preparing nursery beds or heaps on the main fields that are free from pest infestation. This is usually done by removing plant debris, and deep ploughing to submerge eggs of pests stopping their growth.
a. Treating seeds with fungicides or bio-pesticides to control seed borne pests.
b. In like manner, seeds that are of resistant varieties should be used because it plays a significant role in pest suppression.
c. The sowing date can be adjusted in order to escape peak seasons of pests attacks.
d. Cultivated crops should be rotated with crops that are non-host. This can break the life cycle of the pests.
e. Properly spacing plants will make them healthy and less susceptible to pests.
f. Weeds should be properly managed because some harbor pests.
g. Trap crops can be grown on the borders of the fields. Trap crops are the crops that are more preferred by a pest species. Hence, the pests will settle down there and they can be easily annihilated.
Biological practice is the most important component of IPM. It involves the use of living organisms to control unwanted living organisms such as pests. Biological control of pests deliberately uses plant extracts (e.g. neem plants), parasitoids, predators and pathogens to maintain the population of pests below the EIL (Economic Injury Level) by introducing a new bioagent into their habitat or boosting the activities of natural enemies that are already present.
Parasitoids are organisms that lay eggs in or on the bodies of their hosts. They end up killing their hosts while completing their life cycles.
These are free living organisms that prey upon other organisms to get their food. Examples include different species of dragonflies, spiders, lady bird beetles, birds etc.
Some microorganisms are capable of infesting and causing diseases in their hosts which leads to the death of the hosts. These pesticides are formulated using naturally occurring pathogens that can inhibit the growth of or ultimately kill a pest. The major groups of pathogens are fungi, viruses, and bacteria. For instance, different species of Hirsutella have been reported to infest and kill large numbers of pests in the fields.
These diseases can be easily created in the laboratory in liquid or powder formulations and can be sprayed like chemical pesticides. Biopesticides are classified into three (3) distinct classes.
These are methods other than cultural or biological that are used in the control of pests.
a. Removal of plant parts that are diseased and disposing appropriately.
b. Removal and destruction of egg masses and other developmental stages of the pests (for insects).
c. Use of traps to capture pests disturbing crops on the field. Light traps should be used for insects.
d. Installation of bird scarer (such as decoy predator, ultrasonic devices) in the field where required.
e. Pheromones can be used to disrupt mating and to also kill zone creation.
PRINCIPLES OF INTEGRATED PEST MANAGEMENT (IPM)
The strategy of IPM in controlling pests is to start from the simplest to the complex ones. The simpler the methods, the less harm it can cause to the environment and to humans. Usually, the last resort is to use chemical pesticides, which must be judiciously used after carefully monitoring the activities of the pests.
The principles outlined below are followed by IPM:
- Prevention: “Prevention is better than cure”. Hence, taking preventive measures eliminates the need to take further action. For instance, guarding transplanted palm fruits with nets to prevent damage by grass cutters is a typical example of this method. In like manner, crop rotation can be employed to break the life cycle of the pest. This measure will mitigate the loss of plants, and reduce the mortality rate of the plants.
- Identification: Specificity is very important in IPM. It is essential to clearly identify the cause of an emerging problem. Once this is done, it would be easier to know the best and suitable approach to tackle the problem.
- Monitoring: Many techniques of IPM rely on timing. For instance, knowing when the natural predators of a pest are more active increases the effectiveness of complementary control methods. This can be known by regularly inspecting the field to detect when a pest population is growing and where their hideouts are located. Therefore, in extreme cases where chemical pesticides are required, this will increase efficiency of the pesticides.
- Assessment: There are times when you don’t need to take any action against pests. Some pests are categorized as “Circumstantial Pests” because they are only classified as pests depending on their present activities. This is why assessment of the situation is very important. For instance, termite presence in a farmstead may be harmful if they are destroying wooden structures on the farm. However, on the field, they might be helping with the pulverization of the soil.
- Planning: In IPM, various methods of pest control are synchronized. Physical methods (such as mulches, barriers, traps) can be combined with cultural methods (such as resistant varieties, manipulating plant nutrition) and biological methods (such as beneficial organisms, predators) to achieve optimal results. The right combination to use largely depends on the pests you want to control and their activities as you’ve observed.
- Evaluation: After implementing a particular IPM strategy, it is essential to analyse the results if it was expected. Identifying what works and what didn’t encourages record keeping for future reference.
ADVANTAGES OF ADOPTING INTEGRATED PEST MANAGEMENT (IPM)
The benefits of fully incorporating IPM strategies in your farm are numerous. It’s a question of if you are interested in practicing an agricultural system that is harm-free to the environment and yourself or if you don’t care. The major menace IPM is trying to eradicate is the indiscriminate use of chemical pesticides by farmers because of its supposed fast result without paying any regard to the long term problems associated with it.
Here are some of the reasons why you should practice IPM:
- Lower cost: The cost of acquiring chemical pesticides to control pests is higher when compared with IPM. Why? Most of these pesticides are imported. Hence, if you use IPM, you are wisely reducing your financial burden.
- Environmental Friendliness: Chemical pesticides have been consistently linked with the degradation of the environment which is an additional problem. However, IPM is an eco-friendly approach. In fact, IPM first considers the effects of the control measures on the environment before it is applied. In addition, the use of less amounts of pesticides can not affect the fertility of the soil. Also, it reduces the potential for air and ground water contamination
- Pests Resistance: Pests often become resistant to any chemical that is being added consistently, making further control to be unachievable. Since IPM discourages the use of chemical pesticides, the cases of pest resistance are reduced to a great extent.
- Beneficial Organisms: IPM ensures that non-target species are not harmed when applied. These non-target species can be natural enemies responsible for reducing the population of the economic pests. Sometimes, one of the strategies of IPM is to find a way to increase the population of the natural enemies so that they can help to beat down the pests.
- Human Health: IPM discourages the use of chemical pesticides that farm workers and the public are exposed to. This is a growing health concern for humans, because these chemicals can accumulate in humans and then end up causing deadly diseases. However, IPM alleviates public concern about pest and pesticide-related practices.
LIMITATIONS OF INTEGRATED PEST MANAGEMENT (IPM)
- IPM requires technical know-how and domain knowledge experts. Many times, proper understanding about the pest and its activities is required before a control plan can be drafted and implemented. Unfortunately, most farmers are not equipped with this knowledge.
- Unlike chemical pesticides, IPM requires patience and dedication. Much time is needed in planning and strategies differ from regions to regions. Making it impossible to outrightly copy another person’s strategy on your own farm. Sometimes, farmers may worry too much about the long time required to get the expected results of intervention.
- Government support and good policies are not there to further encourage farmers to practice this awesome system of pest control.
Unlike when chemical pesticides are used every time, IPM may not give the desired results because of the short duration of most crops. This, I believe, is one of the fears of many farmers.
However, when this is viewed from the same lens of climate change, I believe it is a good initiative that should be adopted on a large scale all over the world.