What is Plant Pathology?
Plant
pathology is a scientific field that studies plant diseases and aims to
increase plant survival rates when adverse environmental factors and
disease-causing parasite microbes are encountered. Plant pathology is therefore
vital, fascinating, demanding, and deserving of independent study. But it's
also a science with the noble and practical objective of safeguarding the food
supply for both people and animals.
In
certain places, plant diseases make it impossible to cultivate and grow food
plants. In other places, food plants can be grown and cultivated, but they may
be attacked by plant diseases that kill off portions of the plants or the
entire plant and reduce a large portion of the plant's produce—food—before it
is harvested or consumed. To achieve its objective, weed science and entomology
join forces with plant pathology.
Considering
that plant diseases alone result in the loss of 14.1% of crops, the yearly global
crop loss due to plant diseases is estimated to be $220 billion. 6–12% crop
losses following harvest should be added to this; these are especially high in
poor tropical nations with limited resources, training, and refrigeration. Furthermore,
excluded from these losses are losses resulting from environmental variables
including freezes, droughts, air pollution, nutrient shortages, and toxicities.
The
numbers mentioned above, while impressive, do not convey the countless tales of
large populations in many developing nations experiencing starvation, hunger,
and malnourishment as a result of plant diseases; or of lost earnings and
employment as a result of crops destroyed by plant diseases, forcing people to
flee their farms and villages and migrate to densely populated cities in search
of jobs that would enable them to survive.
Plants And Disease
Most
of the earth's living things, such as trees, grass, flowers, and so forth, are
made of plants. All of the food that humans and all other animals rely on,
whether directly or indirectly, comes from plants. For us and other carnivores,
even the meat, milk, and eggs we consume are produced by animals who eat plants.
The ability to transform solar energy into chemical energy that can be stored
and used in the form of carbohydrates, proteins, and lipids is unique to plants
among higher species. These plant materials are essential to the life of all creatures,
including humans.
As
long as the soil gives them enough nutrients and moisture, enough light reaches
their leaves, and the temperature stays within a particular “normal” range,
plants—whether cultivated or wild—grow and produce well. But plants can become
ill too. In addition to exhibiting a variety of symptoms and growing and
producing poorly, sick plants frequently perish in whole or in part. It is
unknown if sick plants experience anguish or suffering.
The
pathogens that infect humans and animals are either the same or very similar to
those that infect plants. In addition to unfavorable environmental factors
including an excess or shortage of nutrients, moisture, light, and air or
soil-borne toxins, they also comprise pathogenic microorganisms like viruses,
bacteria, fungus, protozoa, and nematodes. In addition to being harmed by
insect attacks, plants are also negatively impacted by competition from other
undesirable plants, or weeds. The study of plant pathology typically excludes
plant damage caused by insects, people, and other animals.
Plant Disease: An Overview
It
is challenging to determine when a plant is diseased precisely because it is
unknown if they experience pain or discomfort and since they do not speak or
interact with humans in any other way. When a plant is able to perform its
physiological tasks to the greatest of its genetic ability, it is considered
healthy, or normal. A healthy plant’s meristematic (cambium)
cells divide and differentiate as needed. Various types of specialized cells
take up nutrients and water from the soil, transfer them to all plant parts,
continue photosynthesis, transfer, metabolize, or store the products of
photosynthesis, and produce seed or other reproductive organs for survival and
growth.
When a pathogenic organism or a detrimental environmental factor interferes with a plant's or plant part's cells' capacity to perform one or more of these vital functions, the activities of the cells are disrupted, altered, or inhibited, the cells malfunction or die, and the plant becomes diseased. The condition is initially inconspicuous and restricted to one or a few cells. But soon, the reaction spreads more widely, and the impacted plant sections exhibit alterations that are obvious to the unaided eye. These outward manifestations are the illness's symptoms.
