As an Agriculture
Microbiologist, most of my work is on edaphic stress management. Most farmers
specifically in developing countries blindly follow the recommendations of
fertilizer sellers or simply apply fertilizers in the field without any study
about crop requirement of fertilizer and type of Nutrient deficiency in the
soil. I always recommend farmers for soil testing before the application of
fertilizers. Nutrient management plays a vital role in mitigating abiotic
stresses in plants, it’s also important for controlling several diseases in
plants. Proper nutrient management practices can decrease the effects of
abiotic stresses. In this blog, we see how nutrient management improves crop
productivity tolerance to abiotic stresses.
Improved stress tolerance: Appropriate nutrient management ensures that plants receive an optimum supply of essential nutrients. Stable nutrition enriches plants’ overall health and vigor, making them better equipped to withstand abiotic stresses. Providing adequate potassium benefits plants to regulate water uptake and sustain turgor pressure during drought conditions, thereby reducing water stress and proper application of Potassium (Involved in protein synthesis) is essential for repairing and maintaining cellular structures damaged by abiotic stress. One of the factors crops susceptible to Abiotic stress is negligence in Micronutrient application. Micronutrients, such as iron, zinc, copper, manganese, boron, and molybdenum, are required in smaller quantities but are essential for hormone synthesis, activation, and function. These micronutrients act as cofactors for enzymes involved in hormone biosynthesis and play a role in hormone transport and signaling. Deficiencies in micronutrients can disrupt hormone balance and affect plant growth and development. Appropriate application micronutrient application enhances crop stress tolerance.
Effective Approaches to Abiotic Stress Management in Agriculture
Enhanced nutrient uptake:
Abiotic stresses frequently disturb plants' availability and uptake of
nutrients. Nutrient management strategies, such as applying organic matter,
using fertilizers with slow-release characteristics, or adopting precision
agriculture techniques, can enhance nutrient uptake efficiency. Fertilizers
with slow-release characteristics are designed to provide a gradual and
controlled release of nutrients to plants over an extended period of time
(urea-formaldehyde (UF), methylene urea, and sulfur-coated urea (SCU), Nutrient-Enriched
Zeolite Fertilizers, Polymer-Coated Fertilizers). This ensures that plants can
access and utilize essential nutrients even under stressful conditions.
Regulation of plant
physiology: Nutrients play a critical role in regulating
various physiological processes in plants. For instance, adequate levels of
nutrients like calcium and boron help maintain the structural integrity of cell
walls, reducing the negative impacts of water stress. Nutrient management
practices can optimize the nutrient balance to support essential physiological
functions and minimize the negative effects of abiotic stresses. Nitrogen plays
a vital role in photosynthesis, protein synthesis, enzyme activity, and overall
plant growth and development. Phosphorus is a critical nutrient that is
involved in energy transfer and storage in plants. Boron essential synthesis of
cell wall components and the transport of sugars and other nutrients within the
plant. Molybdenum is involved in nitrogen metabolism and the conversion of
nitrate to ammonium within plants. Calcium is a key nutrient
that plays a crucial role in cell signaling and communication. Deficiency of
nutrients affects the plant’s physiological regulation and can’t survive in the
stress condition.
Scavenging of reactive
oxygen species (ROS): Abiotic stresses can lead to the
production of reactive oxygen species (ROS) specifically in salinity stress,
causing oxidative damage to plant cells. Reactive oxygen species (ROS) are
highly reactive molecules that include superoxide radicals (O2^-), hydrogen
peroxide (H2O2), and hydroxyl radicals (OH^-). Nutrient management, particularly through the
provision of antioxidants such as vitamins, minerals, and secondary metabolites
like auxins, helps in strengthening the antioxidant defense system of plants.
This enables plants to scavenge and neutralize ROS, reducing oxidative stress
and minimizing damage. Ascorbic acid directly neutralizes ROS,
acting as an antioxidant in plants. Tocopherol helps protect cell membranes
from oxidative damage caused by ROS. Essential minerals, including iron (Fe),
manganese (Mn), copper (Cu), and zinc (Zn), are integral to the structure and
function of antioxidant enzymes involved in ROS scavenging. They act as
cofactors for antioxidant enzymes like SOD, CAT, and peroxidases, enabling
their efficient activity.
Root system development:
A well-developed and healthy root system is crucial for plants to withstand
abiotic stresses. Nutrient management practices that promote root growth and
development, such as providing adequate phosphorus and micronutrients, can
enhance the root's ability to explore the soil for water and nutrients,
improving plant resilience to abiotic stresses. Iron is essential for root
development as it plays a vital role in the synthesis of chlorophyll and
various enzymes involved in plant growth processes. It is necessary for the
production of energy, root cell division, and the formation of new cells in the
root tips. Copper is necessary for root development and is involved in several
enzymatic processes, including lignin synthesis and cell wall formation.
Manganese contributes to root elongation, cell division, and the synthesis of
proteins and enzymes required for root growth.
Hormonal regulation:
Nutrients influence the synthesis, transport, and signaling of plant hormones,
which play a vital role in stress responses. Nutrient management practices that
optimize hormone balance, such as supplying nitrogen for the synthesis of
stress-responsive hormones like abscisic acid (ABA), can help plants cope with
abiotic stresses more effectively. The interactions between nutrients and
hormone regulation are complex and can vary depending on the specific plant
species, developmental stage, and environmental conditions. The application of Magnesium
is a vital component of chlorophyll, Calcium plays a crucial role in hormone
signaling, and Iron is a cofactor for many enzymes involved in hormone biosynthesis
and metabolism, Zinc is involved in the production and transport of auxin, a
key growth-promoting hormone, Molybdenum is required for the activity of
enzymes involved in the synthesis and breakdown of plant hormones, including
cytokinins and abscisic acid. Imbalances or deficiencies in nutrients can
disrupt hormone synthesis, signaling, and response pathways, leading to growth
abnormalities, reduced yields, and increased susceptibility to stress.
In conclusion, Nutrient
management is a key strategy for mitigating the negative impacts of abiotic
stresses on plant growth and productivity. By optimizing nutrient availability,
uptake efficiency, physiological processes, antioxidant defense, root
development, and hormonal regulation, plants can better withstand and adapt to
challenging environmental conditions. Proper nutrient management not only
enhances stress tolerance in the crop, it also decreases the cost of
cultivation. Nutrient management in agriculture is a vast topic it’s difficult
to cover in a single blog. In the upcoming, I will explain the nutrient role in
plant stress tolerance in detail.
Reference
Bitla UM, Sorty AM, Meena KK, and Singh NP
(2017). Rhizosphere signaling cascades: fundamentals and determinants In: Singh DP, Singh HB and Prabha R,
(Eds.), Plant-Microbe Interactions in Agro-Ecological Perspectives Vol.-I.
Springer Nature Singapore
Plant Nutrition: An Effective Way to Alleviate Abiotic Stress in Agricultural Crops doi: 10.3390/ijms23158519