Abstract:
Entomology is a branch of Zoology that studies insects and how they interact with their environment, other species, and humans, as well as their management. The word originates with a Greek work Entom, meaning “insect” and logy meaning “study”.
Insects are quite remarkable creatures with about 1 million species rightly identified, while about 8 million are yet to be identified. Entomology under present day consideration is a relatively young Science. It is a profession that we unnoticeably practice every day alongside our daily activities right from sunrise to sunset. Entomology plays a significant role in our daily lives because during the day, we deal with the insects that disturb our crops and animals, and unfortunately, have to contend with the nocturnal ones that transmit diseases to us when we are supposed to have very sound sleep.
There are thousands of Entomologists world-wide dealing with various aspects of insects, including collection, identification, biology, evolution, diversity, physiology, utilization, chemical ecology, morphology, etc.
Over several species of insects attack various crops of economic importance, causing severe harm and reducing economic as well as nutrient values of these crops. The struggle by humans and insects to gain supremacy in this world has existed since the days of Adam and Eve in the garden of Eden. The basic war between the two protagonists has existed because insects claim they inherited the world before the creation or evolution of humans. Humans took over the control of this world and have since caused a lot of discomfort to insects and other creatures, purely due to selfishness and greed. They (insects) therefore seek to engage humans in a great war to take over what they claim are rightfully theirs. This position of insects has created a lot of fear and panic within the human race to the extent that, in trying to counteract the subtle, seemingly harmless posture of insects, humans have resorted to pressing the panic button and in the process, hurting themselves and environment badly. While man rely on sophistications and heavily guarded technology to displace insects, these tiny creatures just make use of their natural brains and wisdom to outwit humans in all technological efforts.
Insects attack crops on the field and in storage due to their feeding and oviposition behaviours such as piercing and sucking, biting and chewing, and boring. They may also transmit diseases to plants and some insects, especially the stored product pests, contaminate food with their body parts, faecal matter and webbings. These activities reduce the quality and quantity of food. Damage to crops by insects (field and stored) world-wide can be up to hundred percent in some cases. This raises serious concerns about the extent of food insecurity in the world and its associated consequences.
In trying to counteract the effect of insects on agricultural production, various studies on issues such as the ever increasing resistance of insects to insecticides, host selection of insects, pheromones, as well as overall management options available, have been carried out by Scientists all over the world. The results of these researches have produced techniques that have been employed to control insect pests, but to date, man has remained hugely unsuccessful.
Results of our studies so far have shown that, most agricultural insect pests, especially aphids and white flies (in Ghana and other parts of the world), have become resistant to human’s deadliest weapon, i.e., insecticides, through various inherent mechanisms such as:
Production of altered forms of carboxylesterase, due to alterations in the parental protein molecule. Proteins E-7, E-9, and E-10 have been found to be responsible for organophosphate resistance in aphids. Thus elevated carboxylesterase resistance is deduced as a major resistance mechanism.
Production of active site of insecticide inhibition by carboxylesterase which serves as “alternative target sites” or “sequestering protein”, by binding permanently to the inhibitor molecule. Thus insecticide hydrolysis is found not to be a mechanism for resistance.
Emergency production of 1-chloro-2,4-dinitrobeneze (CDNB) linked glutathione S-transferase as a complimentary protective enzyme to confer resistance in close conjunction with other pre-existing mechanisms.
Changes in the genomic DNA of resistant insects give rise to gene polymorphism. Thus, gene amplification/duplication is considered an important resistant mechanism.
Other studies such as pheromone extraction, isolation, and identification have also been carried out by my team for various interventions (mating disruption, mass trapping and monitoring) on millet stem borer damage to millet in the Semi-Arid tropics of West Africa.
Exploring the potential of various environment friendly Ghanaian traditional plants (for bio-active compounds) to control field and stored-product insect pests with my students have also revealed very interesting results, giving hope for the future management of insect pests.
Are insects truly dictating the pace of world food insecurity and threatening food shortage and hunger? Results of research carried out by my team and various collaborators over the years point to the fact that, humans are in a state of panic, given true meaning to the word “Entomophobia”, and unquestionably losing the fight against the tiny insects, around the globe. Thus, insects are truly dictating the pace of world food insecurity, leaving humans with very little options to counteract their ruthless upsurge on agricultural crops.