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Scientific study of plant life and development?. BOTANY. STUDY OF THE EXTERNAL STRUCTURE OF PLANTS?. MORPHOLOGY. STUDY OF THE INTERNAL STRUCTURE OF PLANTS?. ANATOMY or HISTOLOGY. Pastures. Annual CROPS. Perennial crops. e.g. GRAPES. Pistachio – perennial tree crop.
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STUDY OF THE EXTERNAL STRUCTURE OF PLANTS? MORPHOLOGY
STUDY OF THE INTERNAL STRUCTURE OF PLANTS? ANATOMY or HISTOLOGY
Perennial crops e.g. GRAPES
Annual - a plant that completes its life cycle in one season and dies (e.g. wheat, subclover, peas, beans) Biennial - a plant that requires two seasons to complete its life cycle. Vegetative phase and flowering phase (e.g. carrot, onion) Perennial - a plant that lives from year to year (e.g. apple, citrus, tea bush) Ephemeral - very short lived plants (e.g. desert and tundra plants) Plant life cycles
Single seed leaf or cotyledon • embryo contains: • coleoptile -- a sheath in which the true leaves and plumule grow • plumule: origin of young leaves --> growing point, crown or node • radicle ---> initial seminal roots • coleorhiza -- protective sheath for the radicle • Tillers - axillary shoots that grow later from the growing point • Secondary roots form later, often with tillering Monocotyledons
Adventitious roots grow from the shoot axis just at or above the soil surface.
seed has 2 seed leaves /cotyledons • cotyledons either hypogeal (below ground) or epigeal (above ground) • embryo • radicle ---> primary root • hypocotyl - lifts the cotyledons above the soil • epicotyl - main stem and growing point • apical and axillary growing points • secondary roots branch from the primary root to form a structured deep root system Dicotyledons
Monocotyledonous plants tend not to have a dominant tap root, instead, the roots branch in many directions creating a fibrous root system. Dicotyledonous plants tend to have a dominant tap root, which develops downward, together with limited lateral root growth.