Temperature

Definition

Temperature refers to the measure of the warmth or coldness of an environment, impacting biological processes such as growth and development. In the context of plant life, temperature plays a vital role in seed formation, germination rates, and susceptibility to fungal diseases. It influences cellular activities, enzyme reactions, and overall plant health, which can affect everything from embryogenesis to the emergence of seedlings and the challenges posed by pathogens.

5 Must Know Facts For Your Next Test

1. Temperature affects enzymatic activity in plants; higher temperatures generally increase reaction rates but can lead to denaturation if too high.
2. Seed development is highly temperature-sensitive; optimal temperatures are necessary for successful embryogenesis and maturation of seeds.
3. Inadequate temperatures during germination can lead to poor seedling establishment and increased mortality rates.
4. Certain fungi thrive at specific temperature ranges, which means temperature changes can either promote or inhibit fungal diseases in plants.
5. Thermal stress, whether too hot or too cold, can significantly impact a plant's ability to absorb water and nutrients, affecting overall health and yield.

Review Questions

• How does temperature influence the processes of embryogenesis and seed development in plants?
  • Temperature plays a crucial role in embryogenesis and seed development by affecting cellular metabolism and growth rates. Optimal temperatures are necessary for proper enzyme function and metabolic processes that lead to successful seed maturation. If temperatures are too low or too high, it can result in poor embryo formation or abnormal seed development, ultimately affecting germination potential and seed viability.
• Discuss how temperature variations can impact germination and early seedling development.
  • Temperature variations have a significant effect on germination and early seedling development. Each seed species has an optimal temperature range for germination; temperatures outside this range can delay or inhibit germination altogether. Furthermore, temperature fluctuations during the early stages of seedling growth can lead to stress responses, stunted growth, or increased susceptibility to disease due to weakened defenses.
• Evaluate the relationship between temperature and the prevalence of fungal diseases in plants, considering climate change implications.
  • The relationship between temperature and fungal diseases is complex; certain pathogens thrive at specific temperature ranges while others may be inhibited. As global temperatures rise due to climate change, conditions may become more favorable for some fungal pathogens, increasing their virulence and prevalence. This shift could lead to higher incidences of crop losses, challenging agricultural practices and food security as plants become more vulnerable to diseases that thrive under warmer conditions.

Related terms

Thermal Regime: The patterns and fluctuations of temperature in a given environment that can influence plant growth and development.

Stratification: A process involving the exposure of seeds to a period of cold temperatures to break dormancy and promote germination.

Pathogen Virulence: The degree of damage a pathogen can cause to a host plant, which can be influenced by environmental factors including temperature.