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Question
Define the term ‘stress’ for plants. Discuss briefly the two types of stress encountered by plants.
Solution
A plant has to constantly interact with various biotic and abiotic factors. These factors may put stress on a plant. Two types of stress that a plant often encounters are as follows:
- Environmental Stress: Environmental stress is produced by unfavourable conditions; like salinity, drought, extreme temperatures, etc. Many crop plants are unable to survive extreme saline conditions or drought or extreme temperatures and hence, stay dormant during these phases.
- Biotic Stress: Biotic stresses come in the form of insects and pests. Weeds also represent biotic stress for plants. While pests and insects do direct harm to the plants, weeds do so by competing for available resources; like sunlight, nutrients and water.
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