Light and temperature interaction
Download
1 / 51

Light and Temperature Interaction - PowerPoint PPT Presentation


  • 80 Views
  • Updated On :

Light and Temperature Interaction. Modified by Georgia Agricultural Education Curriculum Office June, 2002. Fall Leaf Color. cool temps - very bright days. Orange. yellow, reds, purples and browns chlorophyll cells die as temperatures get cooler. Yellow. carotenoids

Related searches for Light and Temperature Interaction

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Light and Temperature Interaction' - lyre


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Light and temperature interaction l.jpg

Light and Temperature Interaction

Modified by Georgia Agricultural Education Curriculum Office

June, 2002


Fall leaf color l.jpg
Fall Leaf Color

  • cool temps - very bright days


Orange l.jpg
Orange

  • yellow, reds, purples and browns

  • chlorophyll cells die as temperatures get cooler


Yellow l.jpg
Yellow

  • carotenoids

  • after chlorophyll dies you see the other pigments that are always present


Red purple l.jpg
Red-Purple

  • anthocyanins

  • not always present

  • synthesized in cooler temps

  • made from sugar molecules


Brown l.jpg
Brown

  • tannins

  • mask or show up more once chlorophyll dies

  • produced in the leaves


Leaf fall l.jpg
Leaf Fall

  • need an abscission layer

  • leaf can no longer translocate carbohydrates out of the leaf


Bright days l.jpg
Bright Days

  • lots of carbohydrates in the leaf

  • anthocyanins get brighter color


The key l.jpg
The Key……

  • cool, short days


Greenhouse effect l.jpg
Greenhouse Effect

  • short, high energy wave lengths of light from sun enters house

  • absorbed by structures and plants


Greenhouse effect11 l.jpg
Greenhouse Effect

  • plants re-radiate green light in longer waves

  • long waves do not have as much energy as the short waves


Greenhouse effect12 l.jpg
Greenhouse Effect

  • longer waves do not have enough energy to escape from the house

  • result is heat


Greenhouse effect13 l.jpg
Greenhouse Effect

  • this is how the earth is heated

  • long waves cannot escape through the clouds

  • cloudy nights are warmer


Light l.jpg
Light

  • energy - electromagnetic radiation

  • wavelengths - distance from peak to peak

  • measured in nanometers “NM”


Far red l.jpg
Far Red

  • color plants use


Infra red l.jpg
Infra Red

  • heat energy


Visible light l.jpg
Visible light

  • light quality - color

  • quantity - intensity, how bright

  • duration - photoperiod


Quality l.jpg
Quality

  • blue - 400-510 NM

  • cell elongation

  • photosynthesis - chlorophyll absorbs red and blue light


Quality19 l.jpg
Quality

  • phototropism - plant tends to grow or bend toward a light source


Slide20 l.jpg
Red

  • photosynthesis

  • stimulates branching

  • encourage growth of auxiliary buds


Slide21 l.jpg
Red

  • phytochrome - light absorbing pigment

  • seed germination in photoblastic seeds


Slide22 l.jpg
Red

  • flowering responses

  • photoperiod



Far red24 l.jpg
Far red

  • promotes stem elongation


Yellow green l.jpg
Yellow - Green

  • does not effect plants


Intensity l.jpg
Intensity

  • measured in foot candles

  • amount per unit area on plant


Plants l.jpg
Plants

  • shade loving

  • too much sun - leaf burn

  • dehydrate

  • kill chlorophyll


Plants28 l.jpg
Plants

  • sun loving

  • low light, pale color

  • new leaves are small

  • lack vigor


Plants29 l.jpg
Plants

  • don’t flower properly if at all


Light30 l.jpg
Light

  • Light Compensation Point -”LCP”

  • light intensity where rate of photosynthesis = the rate of respiration


Slide31 l.jpg
LCP

  • Lowest intensity you can grow a plat at

  • If a plant is grown below this level, respiration will be greater than photosynthesis


Slide32 l.jpg
LCP

  • plant will die

  • for a plant to grow photosynthesis must be greater than respiration


Acclimitization l.jpg
Acclimitization

  • preparing plant for lower light intensity conditions

  • expose to lower light intensity


Artificial lights l.jpg
Artificial Lights

  • Incandescent

  • far red, red - elongation

  • low blue

  • 80% of emitted radiation is heat


Incandescent l.jpg
Incandescent

  • 20% visible light

  • 12% utilized by plant


Flourescent l.jpg
Flourescent

  • red, blue

  • 36% heat energy

  • 22% light used by plant

  • spectral flexibility


Flourescent37 l.jpg
Flourescent

  • can change the quality of the light by changing the coating on inside of bulbs

  • Cool White - Ca Halophosphate


Gro lux l.jpg
“Gro-Lux”

  • coated with Mg Fluorogerminate

  • not as long life as cool white, 30X more expensive


Metal halide l.jpg
Metal Halide

  • increase light intensity


Low pressure sodium l.jpg
Low Pressure Sodium

  • yellow glow

  • energy efficient

  • yellow - orange light


High pressure sodium l.jpg
High Pressure Sodium

  • red, blue light

  • energy efficient


Photoperiod l.jpg
Photoperiod

  • length or duration of the light period

  • biological measurement of relative length of light and dark periods


Photoperiod43 l.jpg
Photoperiod

  • effects

  • flowering

  • leaf abscission

  • dormancy - acclimate for winter


Effects l.jpg
Effects…..

  • Sex expression

  • runner formation

  • tuber formation

  • bulb formation


Short day plants l.jpg
Short Day Plants

  • flower when day length is shorter

  • the dark period is critical

  • it’s dark longer than it is light


Short day plants46 l.jpg
Short Day Plants

  • examples

  • Chrysanthemum

  • Christmas Cactus

  • Poinsettia


Long day plants l.jpg
Long Day Plants

  • flower when days are long and nights are short

  • example: lettuce, radish, petunias


Facilitative long day l.jpg
Facilitative Long Day

  • flower any period

  • if long day - flowering is enhanced

  • examples - tomato, begonia


Day neutral l.jpg
Day Neutral

  • flower under long or short day lengths

  • example: African Violet


Poinsettias l.jpg
Poinsettias

  • use night interrupted lighting

  • turn on artificial lights from 10 p.m. to 2 a.m.

  • splits up the dark period


Poinsettias51 l.jpg
Poinsettias

  • cyclic lighting from 10 p.m. to 2 a.m.

  • lights on for 6 minutes and off for 24 minutes


ad