Unit II – Plant Science

1. Unit II – Plant Science The Importance of Plants

2. Benefits of Plants • Plants are essential to the survival of human beings. • Plants provide biological, physical, and emotional benefits. • Biological • Plants convert CO2 to O2 by photosynthesis • Provide food

3. Benefits of Plants • Physical • Provide materials for shelter • Provide materials for clothing • Provide shade, cooling, and wind control • Reduce wind and water erosion • Provide energy sources • Provide habitat for wildlife

4. Benefits of Plants • Emotional • Provide beauty from landscapes and individual specimens • Provide an enjoyable hobby • Provide a relaxing effect

5. Plant Science Areas* • Four areas of science that are closely related to the study of plants • Botany* the science of plants and consists of anatomy, ecology, physiology, and taxonomy • Horticulture* includes producing, processing, and marketing fruits, vegetables, flowers, ornamental shrubs, and trees; nursery and landscaping; and turf management • Agronomy* the study of field crops and soil management • Forestry* the science of managing trees for lumber, paper, and other wood products

6. Plant Science Plant Parts and Processes

7. Main Parts of a Plant • Plants are made of four main parts: roots, stems, leaves, and flowers. • Each part is essential to the growth or reproduction of the plant. • Roots* • Absorb water and minerals from the soil • Anchor the plant • Food storage area

8. Main Parts of a Plant • Stems • Supports the plant’s leaves and flowers • Leaves* • Major producer of food for the plant (through photosynthesis) • Food storage area • Site of respiration and transpiration • Flower* • Site of sexual propagation • Source of fruit and seed • Attracts pollinators

9. Photosynthesis vs. Respiration* • Photosynthesis is the process by which plants produce their own food. • Sunlight (Chlorophyll) + Water + Carbon Dioxide = Energy (Sugars)+ Oxygen • Respiration is the process by which plants take in Oxygen and release carbon dioxide.

10. How do plants reproduce?* • Sexually • Sexual propagation occurs within the flower as a result of pollination • This produces fruit and seeds • Asexually • Asexual propagation uses vegetative parts • Asexual techniques can produce new plants from leaves, stems, and roots, depending on the plant

11. When you finish this, you should be able to: Understand plant reproduction, the importance of flowers, the pollination process, and the relationship between plants and animals in reproduction. Identify at least three ways plants are able to reproduce. Demonstrate a propagation technique. Identify the parts of flowers. Pay special attention to these key ideas: Flowers are made up of different parts. Flowers need to be pollinated in order to make seeds. Flowers attract insects and animals that aid in the pollination process. Plant structures can be used to start new plants.

12. Flower Parts • Flowers are important in making seeds. Flowers can be made up of different parts, but there are some parts that are basic equipment. The main flower parts are the male part called the stamen and the female part called the pistil.

13. The Stamen • The stamen has two parts: anthers and filaments. The anthers carry the pollen. These are generally yellow in color. Anthers are held up by a thread-like part called a filament.

14. The Pistil • The pistil has three parts: stigma, style, and ovary. The stigma is the sticky surface at the top of the pistil; it traps and holds the pollen. The style is the tube-like structure that holds up the stigma. The style leads down to the ovary that contains the ovules.

15. Other Parts • Other parts of the flower that are important are the petals and sepals. Petals attract pollinators and are usually the reason why we buy and enjoy flowers. The sepals are the green petal-like parts at the base of the flower. Sepals help protect the developing bud.

16. Perfect vs. Imperfect • Flowers can have either all male parts, all female parts, or a combination. Flowers with all male or all female parts are called imperfect (cucumbers, pumpkin and melons). Flowers that have both male and female parts are called perfect (roses, lilies, dandelion).

17. Pollination • When pollination occurs, pollen moves from the male parts to the female parts. Pollen grains land on the stigma and a tiny tube grows from it and down the style into the ovary. The fertilized ovule becomes the seed and the ovary becomes the fruit.

18. The Fruit • When a plant flowers and produces seeds, it also produces something else we all like -- fruit. As you learned, when the ovary ripens, it swells and forms a protective covering around the seeds. This protective covering, or fruit, often finds its way on top of cereal, ice cream, a salad, or just a tasty snack.

19. Pollination • Since flowers can't move, they need to be able to attract pollinators or be built so that wind is able to pollinate them. Flowers attract pollinators like bees, butterflies, insects, and birds with sweet nectar, bright colors, and shapes and structures. Some flowers open at special times to attract pollinators such as night blooming plants that are pollinated by bats.

20. Asexual Propagation • Plants from parts is a form of asexual or vegetative propagation. This process is sometimes called cloning because every new plant is exactly like the parent. One type of cloning uses cuttings--parts of plants that grow into new plants. Both stems and leaves can be used as cuttings. Another kind of cloning is grafting--the joining together of two plants into one. Other kinds of cloning use bulbs or tubers--underground parts that make new plants.

21. There are several common asexual propagation methods

22. There are several common asexual propagation methods

23. Asexual Propagation • There are four main reasons for using asexual propagation. • Some plants do not produce seed or seeds are difficult to germinate • It is usually a faster process than seeding • It is more economical

24. Functions of the parts of the flowers?* • Petals- • Attract insects for pollination • Pistil • Female structure of the flower • Site of fruit and seed formation • Contains the stigma, style, and ovary • Sepal • Protects the flower in the early stages • Stamen • Male structure of the flower • Produces pollen • Contains the anther and filament

25. Germination* • Germination is the beginning or plant growth as seen by the sprouting of the seed • The seed is in a dormant, or resting, stage with a supply of food and a protective seed coat until the requirements for germination are met • The following are needed for a seed to germinate: • Favorable temperature that varies by species • Sufficient moisture • Air • Presence or absence of light (depends on plant species)

26. Annuals vs. Biennials vs. Perennials* • Annuals are plants that complete their life cycle (grows, flowers, produces seed, and dies) in one year • Biennials are plants that grow during one year and flower, produce seed and die during the next year. They live for two years • Perennials are plants that live for more than two years. They can grow year after year without replanting.

27. Monocots vs. Dicots*

28. Process of a seed growing to plant.

29. Process of a seed growing to plant.

30. Plant Science Plant Care Requirements

31. What are the factors affecting plant growth? • *Water • Essential for photosynthesis • Maintains cell shape • Enables nutrients to be absorbed and transported throughout the plant • *Growing medium • Provides support for the roots • Allows water and air filtration and movement • Stores needed nutrients

32. What are the factors affecting plant growth? • *Nutrients (fertilizer) – 16 nutrients essential for plant growth • (Mg Ca N S P K, Cu Zn Fe Mo Mn Cl B, C H O) • *Light • Plants need different levels of light intensity • Light is required for photosynthesis • *Temperature • Plants differ greatly in their tolerance for hot and cold temperatures • Extremes in temperature can cause slow growth, fruit or flower damage, or death of the plant

33. What’s in a bag of fertilizer?

34. What care should be provided for indoor plants? • *Provide proper water • Use a well-drained growing medium • Water plants as needed • Water thoroughly at every watering • *Control humidity levels • *Maintain appropriate temperature range • *Maintain appropriate light levels • *Fertilize the growing medium as needed • *Provide appropriate pinching and pruning • Pinch or prune dead/damaged leaves and branches • Pinch or prune to maintain plant shape

35. What care should be provided for outdoor plants*? • Watering is usually only required during dry periods • Grow in areas where they are adapted • Select tolerant plants for locations where pollution can be a problem • Fertilizer is generally only needed once per year • Prune occasionally to remove dead and damaged leaves and branches • Prune to maintain the plant’s natural shape, when required

36. Rules of Proper Watering • Use a well-drained growing medium • The medium should be porous yet retain water • Water plants as needed • Observe the color of the medium • Test for moisture by touch • Water thoroughly at every watering • Water should flow out the bottom of the container

37. Plant Science The Growing Medium

38. What is soil? • *Soil is the naturally occurring top layer of the earth’s surface that provides food, water, air, and support for plant life. • Soil is a natural resource that humans depend on for food, clothing, and materials for shelter. • Soil is composed of a great amount of life. Scientists agree that there is more life below the surface of the earth than there is above it. • *Soil is not dirt! Dirt is misplaced soil.

39. What are the components of soil? • The ideal soil contains the following components: • *45% mineral matter – inorganic (not from plants or animals) and varies in size • Sand – largest particles • Silt – medium-size particles • Clay – smallest particles • *5% organic matter – originates from a living source, usually a plant or animal • 25% water • 25% air

40. Ideal Soil Components

41. Soil Particle Sizes

42. What is a growing medium? • *Growing medium (singular) or growing media (plural) are the materials in which the roots of plants grow. • The growing medium supports, or anchors, the plant in place, even after watering. • The growing medium must retain sufficient moisture, yet be porous enough to allow excess water to drain.

43. What is a soilless mix and where is it used? • *A soilless mix is a medium that contains no soil. • Soilless mixes contain various combinations of the following materials. • Perlite – gray-white material of volcanic origin used to improve aeration • Vermiculite – heat-treated mica (a very thin, layered mineral) with a high moisture-holding capacity • Peat moss – partially decomposed vegetation with a high moisture-holding capacity • Tree bark – usually the bark of fir, pine, or cedar as a source of organic matter

44. What is hydroponics? • *Hydroponics is a method of growing plants in water (nutrient solution) rather than soil. • *This technique is used to grow high-value crops in greenhouses, especially during the winter. • Some hydroponic systems use sand, gravel, rockwool, pealite, or sawdust rather than soil. • Bare root systems mist the roots of plants at regular intervals with a nutrient solution, use shallow pools with plants floating on the surface, or use recirculating streams of nutrient solutions.

45. Aquarium Hydroponic System