study of the functioning of living organisms, animal or plant, and of the functioning of their constituent tissues or cells
PHYSIOLOGY
it is the science of life and the branch of biology dealing with the functions and activities of living organisms and
their parts, including all physical and chemical processes.
PHYSIOLOGY
____ is a reaction to something, or to a to a question, experience, or some other type of stimulus
RESPONSE
__________happen when we perceive that we’re under stress or danger, whether it’s real or imagined. Thus this _________ to crops refers to the changes in the plant mechanism or metabolism due to an stimuli (may be light, water, CO2, nutrients, etc.)
PHYSIOLOGICAL RESPONSE
PLANT PHYSIOLOGICAL RESPONSE
PHYSICAL FACTORS
temperature
water(rainfall)
light(energy)
soil
air
A better understanding of _________ of crops to the factors of crop production helps in altering the management practices such as to improve the crop yields.
physiological response
Temperature stress in plants is classified
into three types depending on the stressor, which may be _________, _______, __________
High, chilling or
freezing temperature.
The effect of high _____________ on plants is primarily on photosynthetic functions. The
heat tolerance limit of leaves of plants coincides with the thermal sensitivity of primary photochemical reactions
occurring in the thylakoid membrane system.
Temperature
____________ plants show low
germination rates, growth retardation,
reduced photosynthesis, and often die.
Temperature-stressed
Effect of High Temperature
on Plant:
physiological process normally
in the range of ________
0-40°C
Effect of High Temperature
on Plant:
High temperature stress
________ causes injury to plant
Less than 40°C
_______________ stress adversely impacts many aspects of the physiology of plants, especially photosynthetic capacity. If the
stress is prolonged, plant growth, and productivity are severely diminished.
Water
This _____ play important roles in
maintaining normal plant growth, and improving their tolerance
to stress
Reactive oxygen species (ROS)
Plants have three basic
responses or reactions to______
They are ______, __________,_________
light ,
photosynthesis,
phototropism and photoperiodism.
The sensing of light in the environment is important to plants; it can be crucial for
________ and ________
Competition and Survival.
__________ is the process by which green plants and certain other organisms
transform light energy into chemical energy.
Photosynthesis
The growth of or the
movement of an organism
towards light is called
____________
Phototropism
Photo means ____ and tropism
means __________ or
growth in response to.
light, turning movement .
___________ if the plant grows towards light. ____________ if the plant grows away from light.
Positive phototropism, Negative Phototropism
__________ allows the plants
to be in a position to get
sunlight for _________
Phototropism , photosynthesis
The influence of relative duration of day and night on the flowering response of
plants is called ________________
Photoperiodism.
These problems is caused by _____________
*Scorching of leaves
*Chlorophyll content is reduced. This reduces the rate of light absorption and the rate of photosynthesis.
*Excess light intensity is associated with increase in the temperature of leaves which in turn induces rapid transpiration and water loss
*Stomatal conductance declines in response to declining leaf water potentials
*High leaf temperature inactivates the enzyme system that changes sugars to starch
PROBLEMS WITH THE EXCESS Light
This phenomenon was first
discovered by Garner and Allard(1920)
Photoperiodism.
_________, a morphological manifestation of the adverse effect in inadequate
light: it develops white, spindly stems, elongated internodes, leaves that are
not fully expanded, and a stunted root system. It is also caused by the deficit of light.
Etiolation
