Mechanisms of Metalloid-Induced Biotic Stress Tolerance in Plants
PB Kale, PV Jadhav
The role of metalloids such as Silicon (Si), Boron
(B), and Selenium (Se) in enhancing plant resilience against biotic stresses is
complex and multi-dimensional. These metalloids contribute to plant defense
through structural reinforcement, biochemical responses, molecular signaling,
and priming mechanisms, all of which reduce the impact of pathogens, pests, and
other biotic stressors. Here, we outline these mechanisms to illustrate the
potential of metalloids in sustainable biotic stress management in plants.
1. Cell
Wall Reinforcement
One of the
primary roles of Silicon in plant defense is the reinforcement of cell walls,
acting as a physical barrier to biotic stressors.
1.
Silicon Deposition: Silicon
is absorbed and deposited as amorphous silica in cell walls, particularly in
the epidermis. This deposition strengthens the cell wall, making it harder for
pathogens to penetrate plant tissues.
2.
Resistance to Herbivory: The
increased rigidity of Silicon-enhanced cell walls deters herbivorous insects
and reduces damage from chewing and piercing-sucking activities, indirectly
lowering pathogen entry points.
