1. Environmental Factors of Plant Production
Ag. 514

2. Five Requirements for Plant Growth
Sunlight
Temperature
Moisture
Air
Nutrients

3. Most Important Requirement for Plant Growth and Survival
Water
Conducts nutrients
Cell composition
Structure/turgidity

4. Most Important Factor Affecting the Adaptation of Plants to a Region
Temperature
Temperature varies with:
Latitude
Altitude
Topography.

5. Temperature is created by heat energy, in the form of solar radiation.

6. Latitude Latitude –how far north or south further north = less sun
Further south = more sun

7. Altitude/Topography Topography The lay of the land
South- and south-western facing slopes receive more solar radiation.
Higher altitudes and northern latitudes are associated with colder temperatures

8. The Palouse

9. Seasonal fluctuations in temperature influence growth by determining the optimum length of growing conditions for a plant species.

10. Surface temperature / varying factors
Heat transfer from the surface as it warms from the morning sun to the atmosphere, as it cools at night.
Plant growth is greater at night, when temperatures cool.

11. Plant adaptation to cold temperatures is known as a plant’s hardiness
Plant adaptation to cold temperatures is known as a plant’s hardiness. Tender plants cannot tolerate extremes in cold temperatures.

12. Evaporation
Water changes from a liquid to a gaseous state.

13. Micro and Macro Environments
The macroenvironment
The atmosphere surrounding a plant.
The microenvironment
The area at ground level immediately surrounding a plant; the plants “personal” space
Microenvironments can be manipulated to support plant growth.

14. The Three Areas of the Plant Environment
Atmospheric
Related to the air
Edaphic
Related to the soil
Biotic
Related to the organisms’ living in the soil

15. Atmospheric Environment
Includes the macroenvironment of the plant.
Can include simulated plant environment (e.g., greenhouse) or natural plant environment.
Atmospheric conditions include:
Temperature
Moisture
Light
Wind.

16. Atmospheric Environment (Cont’d.)
Weather systems tend to be regionally consistent, and play a large role in plant adaptation.
How does the weather in Meridian compare with the weather in Honolulu?

17. Weather Comparisons Meridian Honolulu Record high 105 Record low -26
Average high 68
Average low 38
Total rain fall 9.94
Honolulu
Record high 95
Record low 52
Average high 85
Average low 70
Total rain fall 18.3

18. Atmospheric Environment (Cont’d.)
Cycles of day and night effect plant growth, exhibited by comparing plant growth at different latitudes.
Temperature is affected by latitudinal distance from the equator.

19. Plants receiving both types of rays exhibit normal growth.
How much light and the type of light a plant receives affects its growth cycle.
Angular rays of morning promote cellular elongation.
Perpendicular rays of midday promote cellular stunting.
Plants receiving both types of rays exhibit normal growth.
Direct sun causes compact growth.
Shading creates longer, taller plants.

20. Atmospheric Environment (Cont’d.)
Water
Protoplasm in plant cells is primarily water.
Water uptake increases cell turgidity.
Turgor pressure = force exerted outward on the plant cell wall
Water is essential to increase plant hardiness in hot weather.

21. Atmospheric Environment (Cont’d.)
Water vapor
Transpiration (absorption, transport, and release of water to the atmosphere) cools leaves.
Evapotranspiration (ET) is the rate of transpiration as affected by the rate of evaporation.
The ET rate is used because it is difficult to distinguish where water vapor is coming from - soil evaporation or plant transpiration.

22. Atmospneric Environment (Cont’d.)
Moisture availability to plants
Precipitation (rain and snow)
Water vapor (relative humidity)
Dew (condensation - when air temperature is warmer than surfaces)
Wind / air movement
Velocity is the key factor.
Breezes cool a plant in hot weather.
Wind kills plants in hot weather
Storms can damage or destroy plants.

23. Edaphic Environment Soil environment surrounding the plant.
Soil horizons
Soil particle structure
Soil organic matter
Water movement through the soil
Percolation (from surface into soil structure)
Capillary (wicking action upward)
Gravitational (downward flow)

24. Edaphic Environment (Cont’d.)
Aeration
Air into and through soil
Upward and out of soil
Temperature
Soil warmth is essential for seed germination. pH
Soil acidity or alkalinity creates conditions for plant adaptation and growth.
Salinity
Soil salinity (salt in the soil) creates conditions for plant adaptation and growth. Plants vary in their tolerability to saline conditions.

25. Edaphic Environment (Cont’d)
Biomass
Source of organic matter in soil.
Living (standing crop matter and living organisms).
Non-living (decomposing and decomposed (humus) vegetative and animal matter).
A healthy soil has a diverse biomass for its source.
Competition for water, space, and light is balanced between plants.
Competition between organisms is balanced within the soil, allowing plant roots to receive essential nitrogen.

26. Biotic Environment Biotic and Abiotic Environment
Biotic: living components of the biosphere.
Abiotic: non-living (physical and chemical) components of the biosphere.

27. Biotic factor: the influence of organisms upon other organisms (i. e
Biotic factor: the influence of organisms upon other organisms (i.e., shading, competition, symbiosis, commensalism, parasitism).
Includes man’s influence on plant life by cultural practices, or by creating damaging conditions for plants.

28. Negative influences: Positive influences:
Soil compaction compression of soil, reducing availability of water and air; limits root growth.
Wear Loss of vegetation due to excess traffic through an area (i.e., a worn path through a lawn).
Wasteful pesticide management
Over-fertilization
Wasteful irrigation practices.
Positive influences:
Selection of adaptive plant species for use in the landscape.
Limited cultural practices on plants (limited to the basics).

29. Best strategy is to incorporate best management practices in plant culture:
Selective pruning
Selective fertilization and irrigation
Composting
Mulching
Soil aeration
Integrated pest management
Controlled impact zones (minimize compaction and wear).

30. Record-keeping in plant culture - a best management practice.
Successful record-keeping includes:
Deciding what data needs to be recorded
The most useful system of recording the data
Easy access to the recorded information.
Records should correspond with container labels.

31. Crop records should include five basic elements of plant culture
In each batch:
Variety and propagation date (seeds or cuttings)
Number of seeds / cuttings sown
Number of transplants / date
Ready-for-plant date
Cultural procedures used for the particular plant variety, including containers used (germination, transplant, and sale containers, if different).

32. Good record keeping is essential to good science.
Recording allows the prediction of outcomes and the anticipation of possible problems (unexpected variables).
Good records lead to problem resolution based on facts (occurrences).
Facts are generalizable to similar situations, making their application useful to predict similar outcomes (increasing dependability of results