Agriculture has undergone some transformations throughout history, some based on empiricism and others more on superstition. The reforms that have been preserved today have undergone a kind of natural selection, discarding those that are not productive enough to perpetuate the system. Of course, the primary objective of modifying the method of cultivation is to take advantage of a natural or artificial characteristic of nature in order to favor a better product - lower production price and higher quality. Pesticides are therefore an indispensable element on a farm.
A pesticide usually consists of a chemical agent with a specific formula, which has one or more mechanisms of action by which it prevents reproduction or directly causes the death of the insect that comes into contact with it. However, pesticides are actually considered to be those that affect other herbivores considered pests, such as rodents. The problem is that some traditional pesticides can interfere with the natural ecosystem, causing significant losses of diversity. In addition, there have been dozens of human deaths due to contamination by chemical pesticides, although these intoxications are usually caused by operators who administer these compounds and not by consumers. In any case, due to the bad reputation and the negative effects in the eyes of the consumer, there remains a large market niche for biopesticides, since, on the one hand, it could increase production by being more effective than a normal pesticide and on the other hand, it could stop having these harmful effects.
3 Major types of Bio-pesticides
A bio-pesticide is simply any chemical that acts similar to a pesticide but is not harmful to other living things and is produced by them, not chemically. Although it may seem that all bio-pesticides act under the same premise, this is not so. There are three main mechanisms by which they can operate.
Firstly, we have the bio-pesticides derived from biochemical pathways of a particular organism. They consist of controlling the ethology of pests by means of specific molecules, such as insect pheromones.
Secondly, we have microbial bio-pesticides. They are a very particular type of pesticide since they are based on plant-microbe interaction to favor the plant's physiological response to pathogens or herbivores. They can induce the manufacture of toxic proteins, plant growth, or the inhibition of an infectious process.
Finally, we have a peculiar biopesticide, based on the introduction of genetic material coding for a specific protein. This protein will be expressed in situations of specific stress, allowing the maintenance of a favored immunity.
Current State & Research
There is a multitude of proposals flourishing in this field. BioPhero uses the aforementioned pheromones through fermentation with yeast. AgroSpheres understands that the biodegradation that bio-pesticides boast (which is why they are non-polluting) can precisely diminish their efficacy by degrading before they have finished their function. Its AgriCell technology, therefore, attempts to mitigate this characteristic with an ingenious dosage of RNAi, a type of nucleic acid that regulates gene expression by inhibiting specific functions.
Another area of focus is WeedOUT, as they are trying to increase crop yields in the face of "weed" proliferation. It is clear that other plants will try to colonize the substrate that the farmer cares for so much, so they will end up competing with the crop. In nature, this interspecific competition is preserved because it has multiple evolutionary advantages, but it is not in the farmer's interest to lose yield. A very ingenious solution is to release sterile pollen during the flowering period of weeds, so that most plants will be pollinated unsuccessfully, leading to a systematic abortion of a whole generation of seeds. There are as many options as there are elements that can be modified in a plant. Public research is focused on discovering possible avenues for molecular action, and private initiative is responsible for putting many of these ideas into practice.
The fate of pesticides is by no means uncertain. They have long been used as a basic building block in agricultural production. The biocide of the future must provide safety to the consumer and the farmer, as well as being respectful of the ecosystems (macro- and micro-biotic) that interact with it. The only way for this not to happen is to introduce an element that is necessarily biological, and not synthetic with biological action.
The imperative need for increased yields in production will provide the right climate for the proliferation of a new generation of pesticides based on genetics and the plant immune system. It turns out that most diseases of cultivated plants are caused by viral or bacterial infection. Although their origin is caused by transmission via herbivory - by producing an opening in the organism - the ability in this plant to avoid the proliferation of these bacteria depends entirely on its immunity. Plants have a complex system of hormones and toll-like receptors that end up identifying and recognizing molecular patterns of pathogens (PAMPs).
In fact, a breakthrough in this field would be to parameterize the complex response of plants to herbivory stimuli, which already exist naturally. These are based on the emission of a pattern of gases called VOCs, which detect other plants even of different species, even insects that have co-evolved with them (such as bees) to identify the status of the community in the face of stress. Biotechnology can take advantage of this in many ways, as it is a language that is just beginning to be deciphered.