What are the effects of drought stress and its mechanism in plants?
The plants exposed to water stress deficit produce ROS that can cause and oxidative damage to the biomolecules such as carbohydrates, proteins, lipids and nucleic acids; and therefore, reducing the photosynthesis, respiration and growth of plants [182]. Both salt and drought stress cause osmotic stress, which involves the regulation of a wide range of inorganic and organic metabolites and results in damage to plants, including ion toxicity, reactive oxygen species (ROS) accumulation, plasma membrane disruption, and cell wall damage [6].For drought stress induction, seed priming, growth hormones, osmoprotectants, silicon (Si), selenium (Se) and potassium application are worth using under drought stress conditions in plants.During biotic stress, plants activate various hormonal pathways to cope with the stressor [13,16]. The Jasmonic acid (JA) pathway plays a crucial role in plant defense against insect herbivores, necrotrophic fungi, and some bacterial pathogens.In response to drought stress, plants activate their drought response mechanisms, such as morphological and structural changes, expression of drought-resistant genes, synthesis of hormones, and osmotic regulatory substances to alleviate drought stress.
What are the three types of effects of drought?
The many different drought impacts are often grouped as “economic,” “environmental,” and “social” impacts. All of these impacts must be considered in planning for and responding to drought conditions. Drought can lead to decreased water quantity and quality, increased incidence of illness or disease, increased mortality rates, and adverse mental health outcomes as livelihoods are challenged.Depending upon how severe the conditions get and how long they last, drought can devastate crops, dry out forests, reduce food and water available for wildlife and livestock, restrict recreational activities, and stress businesses and economies.There are several types of drought: (i) meteorological, caused by a long-term deficit of rainfall; (ii) hydrological, caused by a deficit in river flow; (iii) pedological, attributed to a shortage of soil-water storage (green water) in the profile or soil solum (surface and subsurface layers that have the same history .Drought can lead to decreased water quantity and quality, increased incidence of illness or disease, increased mortality rates, and adverse mental health outcomes as livelihoods are challenged. During drought conditions, fuels for wildfire, such as grasses and trees, can dry out and become more flammable.
What are the mechanisms of stress in plants?
These mechanisms include stress perception, signal transduction, transcriptional activation of stress-responsive target genes, and synthesis of stress-related proteins and other molecules, which assist plants to cope with adverse environmental conditions through biochemical and physiological manifestations. Plants in their natural habitats adapt to drought stress in the environment through a variety of mechanisms, ranging from transient responses to low soil moisture to major survival mechanisms of escape by early flowering in absence of seasonal rainfall.The hormone ABA plays a pivotal role in regulating various developmental processes and adaptive stress responses in plants. Recent advances have highlighted the complex interplay between ABA and other hormones or signaling molecules for achieving stress tolerance in plants.These mechanisms include stomatal responses, ion transport, activation of stress signaling pathways, and responses to protect photosynthesis from injury. Understanding these key factors will enable us to improve plant productivity during water stress.The stress hormone that helps plants respond to drought is abscisic acid. The plant hormone abscisic acid (ABA), also known as the stress hormone, induces the closing of stomata during severe drought conditions to prevent water loss. ABA also increases the tolerance of plants to various kinds of environmental stresses.Drought tolerance in plants involves three main mechanisms: morphological, physiological, and genetic/molecular. Morphological mechanisms include drought escape and avoidance strategies like early reproduction or reduced water loss through waxy leaves.
What is the main cause of the drought?
The Short Answer A drought is caused by drier than normal conditions that can eventually lead to water supply problems. Really hot temperatures can make a drought worse by evaporating moisture from the soil. Drought management refers to the systematic preparation, monitoring, and implementation of strategies to mitigate the adverse effects of drought on communities, focusing on needs such as water, food, sanitation, health, and social security, while ensuring coordination among various organizations involved.Water Conservation. One of the easiest steps we can take to help mitigate the impacts of drought is conserving water. If we use water wisely at all times, more water will be available to us and to plants and wildlife when a drought happens.There are four stages to describe and manage drought response: prolonged dry weather, drought, severe drought and recovery. Understanding these stages helps us prepare, respond and adapt, especially as extreme weather is now more frequent due to climate change.
How do plants respond to drought stress?
In response to drought stress, plants activate their drought response mechanisms, such as morphological and structural changes, expression of drought-resistant genes, synthesis of hormones, and osmotic regulatory substances to alleviate drought stress. Drought stress reduces plant height, root length, leaf area, plant biomass and the area of root aerenchyma. Proline leaf content increased significantly at a PEG concentration of 30%.A reduction in the number of leaves per plant, a reduction in leaf size, and an increase in leaf senescence are only a few of the detrimental effects of drought stress during the vegetative period [150,151,152,153]. Another important physiological response that occurs in response to water stress is leaf rolling.Cellular damage: Prolonged water stress can lead to cellular damage and disruption of various physiological processes in plants. This can result in reduced nutrient uptake, impaired metabolism, and even cell death.Drought stress is an abiotic disorder that causes wilt, growth reduction, early onset of fall colors, and premature leaf drop in trees and shrubs. It occurs when the amount of moisture in the soil no longer meets the needs of the plant.