As most agricultural regions are predicted to experience considerably more extreme environmental fluctuations due to global climate change, Plants would need to navigate these environmental stresses by developing tolerance, resistance or avoidance mechanisms.
Among the various environmental stress conditions, Cold temperatures are the cause of enormous agricultural losses, especially in sub-tropical and temperate grain crops. That is because when a cell freezes, the water inside it expands as it turns to ice. This can cause the cell membrane to rupture and lead to cell death.
Cold Stress During Plant Development Stages
Seed germination and vigor are prerequisites of particular importance for the establishment of crop plants, however at cold temperatures, seedling emergence is delayed.
Cold stress intensifies ROS (Reactive Oxygen Species) production in plants’ cells. Excess production and the accumulation of ROS causes oxidative damage at cellular level, disrupts cellular membranes, and leads to enzyme inactivation, protein degradation, and ionic imbalance in plants
Futhermore when plant are exposed to cold temperature during reproduction, it induces flower abortion, pollen and ovule infertility, causes breakdown of fertilization and affects seed filling, leading to low seed set and ultimately low grain yield
Amidst all this constraint, Plants respond to cold temperatures by activating metabolic pathways that protect their cells from cold and freezing conditions. One protection strategy is to accumulate sugars, which decreases the temperature at which ice forms, similar to the effect of putting salt on roads. Another is to produce proteins that stabilize membranes to help them resist rupture.