Introduction
Commonly, termites are silent destroyers and are culpable for losses worth billions of dollars every year. They are among the most dangerous structure and forest insect pests because of their ability to digest wood and other cellulose material. The conventional chemical-based methods of treatments are efficient but can also be associated with environmental and health risks. Therefore, the present focus is turning toward biological control methods. This review paper mainly focuses on various biological control measures for different termite species, with an emphasis on natural and environmentally friendly approaches.
Understanding Termite Behaviour
For effective control of termites, a basis in their behaviour is essential. Termites live in colonies, remain hidden from one’s vision for most of the time, and consist of workers, soldiers, and reproductive termites. Wood, paper, or any plant is their major diet, derived from cellulose. Their patterns of behaviour need to be understood to make them amenable to the biological control methods.
Why Biological Control of Termites?
Biological control methods are preferred for various reasons. They are the most friendly method of control and carry fewer health risks for humans and pets. In many cases, biological controls target mono-phagous pests with no damage to beneficial organisms. Moreover, biological control measures can play significant roles in ecological systems for a long time.
Termite Species Overview
There are more than 2,600 of them that can be broadly categorized into three, namely subterranean, dry wood, and damp wood. Every species has its peculiar characteristics, behaviour, and territory habitat, calling for different control measures.
Subterranean Termites: Features and Habitation Area
Amongst the category, it is one of the most destructive termites. There are massive colonies found underground, and mud tubes are created to transport themselves above ground. The colonies count to several hundreds of thousands to millions of termites.
Drywood Termites: Key Characteristics and Habitats Drywood termites infest dry wood and do not need contact with soil. Its habitats can be furniture pieces, structural wood and wooden articles. As opposed to subterranean termites, it drives out its faecal pellets, which can often be seen surrounding the location of an infestation. Dampwood Termites: Biology and Damage
Dampwood termites seek out highly water-saturated wood and are frequently found in rotting logs, stumps, and structures with wet wood. They seldom require soil contact and if conditions are moist, they can cause severe damage to structures.
Bio-Control Agents for Termitic Management
Bio-control of termites with promising potential is represented by the use of natural enemies, pathogens, and parasites that are capable of suppressing termites. Among these, some of the frequently used and promising agents include
Nematodes: Safe Termite Killers
Nematodes: Microbial Parasites
Among the microscopic worms, nematodes may be made to act as a very effective biological control for termites. Nematodes included in this group are those belonging to the species Steinernema and Heterorhabditis, which are the beneficial nematodes being introduced into the bodies of termites. Symbiotic bacteria are then poured into the body, thereby killing the host in just a short period of 24-48 hours.
Fungi: Effective Biological Controls
Among the pathogenic fungi included in these effective biological controls for termites are those belonging to the species Metarhizium anisopliae and Beauveria bassiana. These fungi can infect and kill termites by penetrating the exoskeleton and then the feeding multiply inside them.
Helpful In Innovative Termite Control with Bacteria
Pathogenic bacteria like Serratia marcescens can also be used in termite control. These bacteria secrete toxic substances that are ruptured in the digestive system of the termites. Ultimately, it causes its death.
Parasitic Wasps/Nature’s Pest Control
Kleptoparasitic wasps lay eggs inside the termite colony. The developing wasp larvae feed upon the termite eggs, and sometimes on the larvae, population to reduce the population of these insects to a great extent.
Beneficial Nematode and How Do They Work in
The beneficial nematodes will invade termite galleries in search of their hosts. Once inside the termite, they release bacteria that multiply profusely, eventually killing it with septicemia. This results in the death of the termite within just days.
Nematode Application for Termite Control
The application of nematodes involves mixing them with water before spraying them on the infested areas. They have to be applied at the cooler times in the day to prevent desiccation and thereby ensure they infect the termite nests effectively.
Fungal Pathogens: Metarhizium and Beauveria
Metarhizium anisopliae and Beauveria bassiana are entomopathogenic fungi that become attached to termite cuticles and, after germination, penetrate the host’s body. The spores grow endophytically within the termite, leading to the mortality of the host.
Use of Fungal Spores in Termite Control
The fungal spores can be surface-applied in termite-infested places or used in bait systems. Both methods ensure termite infection with the respective spores, which is carried back to the colony by the infected termite.
Bacterial Treatments: High-impact Solutions
Bacterial treatments, such as those using Serratia marcescens, could be delivered via soil drenches or bait stations. The bacteria are consumed by the termites, infecting the internal tissues and killing the colony.
Bacteria in Termite Guts: Symbiont Disruption
The ability of termites to digest cellulose occurs through bacteria in the termite’s gut. The introduction of particular bacterial strains may disrupt this symbiosis and can often result in termite populations starving and dying off.
Termite Parasites: Optimized Control Agents
Certain parasitic organisms, such as nematodes and parasitic wasps, attack living termites. These parasites can dramatically bring down termite populations by attacking and killing all stages of life in the colony.
Insect-Parasitic Wasps: Lifecycle and Impact
Insect-parasitic wasps belong to the family Eulophidae, and their eggs are deposited in or on termite eggs or larvae. The larvae of the wasp feed on the termite eggs and larvae, thus regulating the population of termites.
Integration of Biological Control into Pest Management
Biological control should be integrated as part of the overall pest management scheme with other practices: monitoring, habitat modification, and mechanical practices.
Benefits of using Biological Control
Advantages of biological control include the fact that it is more environmentally friendly, target-specific, and reduces the risk of resistance development in termite populations, unlike chemical treatments. Also, control measures can be established by the natural enemy populations for long-term control.
Challenges and Limitations of Biological Control
In addition, this method of controlling termites has limitations: it may require long time frames to achieve results, may be specific to certain species of termites, and its efficiency may be affected by conditions in the environment in which it is applied.
Case Studies: Successful Biological Control of Termites
There are many case studies which demonstrate the effectiveness of the biological termite control method. For example, the addition of Metarhizium anisopliae in buildings infested by termites reduces the activity of termites, which ultimately lowers the damage.
Future of Biological Control for Termites
The future of biological control in the arena of termite management looks bright as research into new agents and new methods is in progress. Advances in biotechnology and genetic engineering offer even greater potential for more effective and targeted biological control solutions.
Conclusion :
Biological control measures on many species are alternatives to chemical treatment against termites and are friendly to the environment and sustainable. Management of termite populations or reductions in their damage levels can be achieved using natural predators, pathogens, and parasites. To merge biological controls in self-sustained pest management, research is in constant advancement.
Frequently Asked Questions
What are the main types of termites?
There are three common termite varieties: subterranean, dry wood, and damp wood, which differ in characteristics and habitats.
Which of the following are lethal to a termite?
Nematodes can kill a termite by
Getting inside the termite’s body by releasing symbiotic bacteria within it
Nematodes cause termite septicemia, which invariably kills the termite within a couple of days.