Abiotic stress
- Also known as
- crop stress, heat stress, drought stress
Abiotic stress is stress on a plant caused by non-living environmental conditions, such as drought, heat, cold, salinity, flooding or nutrient imbalance, as opposed to biotic stress from pests, diseases and weeds. It is a leading cause of crop yield loss.
What is abiotic stress?
Crops respond to their environment constantly, and conditions outside their comfortable range become stress. Abiotic stress is stress from non-living factors:
- Drought, when water supply falls short of demand.
- Heat, especially during flowering and grain or pod fill.
- Cold and frost.
- Salinity, from salty soils or irrigation water.
- Flooding and waterlogging, which starve roots of oxygen.
- Nutrient deficiency or toxicity.
- Excess light, ultraviolet radiation or air pollution such as ozone.
Biotic stress, by contrast, comes from living organisms: insects, diseases, nematodes and weeds.
How abiotic stress reduces yield
- Reduced photosynthesis. Under drought and heat, plants close the pores in their leaves, called stomata, to save water, which also limits carbon dioxide uptake and growth.
- Cell damage. Stress generates reactive oxygen species that damage membranes, proteins and chlorophyll.
- Reproductive failure. Many crops are most sensitive around flowering. Heat and drought at pollination can cause poor seed set, as in corn at silking, with losses that cannot be recovered later.
- Shortened grain fill, which reduces kernel or seed weight.
Stress often comes in combinations, such as heat and drought together, which can be more damaging than either alone.
Managing abiotic stress
- Choosing adapted varieties and planting dates to avoid the worst stress at sensitive stages.
- Water management, through irrigation scheduling and practices that improve water infiltration and storage.
- Balanced nutrition, since well-nourished plants tolerate stress better.
- Soil health, which buffers roots against drought and waterlogging; see soil health.
- Biostimulants, which by legal definition include products intended to improve tolerance to abiotic stress, often timed ahead of expected stress or around critical growth stages.
Abiotic stress and Locus
Locus’s Bombigro foliar biological is positioned around supporting crops through heat, drought and other environmental stress during critical growth stages.
Frequently asked questions
Abiotic stress comes from non-living factors such as drought, heat, cold and salinity. Biotic stress comes from living organisms such as insects, pathogens and weeds.
Usually around flowering and early seed development. Stress at pollination can permanently reduce the number of seeds or kernels set.
Sources
- Crop responses to drought and heat stress, FAO and peer-reviewed plant physiology reviews
- Plant biostimulants: definition, concept, main categories and regulation, P. du Jardin, Scientia Horticulturae, 2015