Introduction to Horticulture Ag. 514

What is horticulture? Horticulture is the industry and science of plant cultivation including the process of preparing soil for the planting of seeds, tubers, or cuttings. The word horticulture comes from the latin hortus or horti, meaning garden, and cultus, meaning to cultivate.

Arboriculture Floriculture - Landscape horticulture Olericulture Pomology Viticulture Oenology Trees Flowers Landscape plants Vegetables Fruits Grapes All aspects of wine and wine making

The Importance of Plants Without plants, life on earth could not exist Plants are the primary source of food for humans and animals

The Importance of Plants cont. Plants also: Provide oxygen Provide shade Supply us with medicines Renew the air Slow down the wind Hold soil in place Are a home for wildlife Furnish building materials and fuel

Parts of the Plant Most plants are made up of four basic parts: Leaves Stems Roots Flowers (these later become fruit or seeds)

Leaves Are the food factory of the plant They produce all of the food that is used by the plant and stored for later use by the plant or by animals

Leaves Come in All Shapes and Sizes! Needles on an evergreen are actually very narrow leaves The spines on a cactus are leaves Some leaves are flat like blades of grass Other leaves, like onion leaves, are cylindrical The shape and size of leaves helps to identify plants

Leaf Cells Chloroplasts Photosynthesis Food making cells Chlorophyll - green color Photosynthesis Process by which chloroplasts make food The oxygen created is used directly by people and animals Without O2 there would be no burning, rusting, or rotting

6H2O + 6CO2 ----------> C6H12O6+ 6O2 Photosynthesis LIGHT 6H2O + 6CO2 ----------> C6H12O6+ 6O2 Six molecules of water plus six molecules of carbon dioxide in the presence of light produce one molecule of sugar plus six molecules of oxygen

Plant Food Food made in the leaves moves down the stem to the roots It is then used by the plant or stored in the roots or stem as sugar, starch, or protein The plant is also used as food for people and animals The leaves are usually the most nutritious part

Respiration Plants breathe 24/7 They consume CO2 and release O2 Roots, stems, and leaves all need O2 to grow Plants produce more O2 during photosynthesis than they consume while breathing

Stems Stems have 2 main functions: The movement of materials Movement of water and minerals from roots up towards the leaves Movement of manufactured food from the leaves down to the roots Support of the leaves and reproductive structures Flowers and fruit or seeds

Stems cont. Stems are also used for: Food storage Reproductive methods Irish Potato Reproductive methods Stem cuttings or grafting Green stems manufacture food just like leaves

Unique Stems Irish Potato & Gladiolus Very different stems Stems are used for food storage and plant reproduction                             

What do we do with Stems? Food Building Materials Asparagus Irish Potato Celery Building Materials Wood

Roots Usually underground – not visible Functions: Anchor the plant and hold it upright* Absorb water and minerals from the soil & conduct them to the stem* Store large quantities of plant food* Propagate or reproduce in some plants * = essential to all plants

Root Propagation Plants with tuberous roots: Dahlia Peony Sweet Potato Are propagated by separating the root clump or by rooting spouts from the root

Roots as Crops Cash crops Carrots Beets Radishes Sweet Potatoes Sugar Beets - Sugar Radishes Sweet Potatoes

Flowers, Fruits, & Seeds Flowers are pretty & contain nectar in order to attract insects These insects fertilize the flower by pollination Pollination begins fruit and seed formation                                 

Flowers are Important! Many plants are grown only for their flowers Floriculture industry in a multimillion dollar business!!!

Flower Construction Insects looking for nectar have to climb over the anther and brush pollen on their legs As they climb towards the center looking for food, they deposit pollen on the stigma

Pollen

Fruits & Seeds Fruits and seeds are eaten, collected, and spread out by animals and people This reproduces the plant

Monocots vs. Dicots