1 / 11

Plant Environment: Water

Plant Environment: Water. Water makes up 80-90% of herbaceous and 50% of woody plants. Water is important to plants. Water critical for plant growth (photosynthesis: 6CO 2 + 6H 2 O ---> C 6 H 12 O 6 + 6O 2 ). Water needed to obtain nutrients from soil (nutrients dissolved in water).

Download Presentation

Plant Environment: Water

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Plant Environment: Water • Water makes up 80-90% of herbaceous and 50% of woody plants • Water is important to plants • Water critical for plant growth (photosynthesis: 6CO2 + 6H2O ---> C6H12O6 + 6O2) • Water needed to obtain nutrients from soil (nutrients dissolved in water) • Water needed for cell elongation, one way plant tissues increase in size

  2. Plant Environment: Water • From soil into root cells • Water enters root hairs (projections of cells above root tip) • How does water move through plants? • Root hairs greatly increase surface area for water entry • Root cells ‘pump’ minerals into cells (using ATP energy) • High concentration of minerals inside roots creates osmotic gradient (difference in water concentration) • Water moves from high to low water concentration • Adding minerals into roots decreases the concentration of water in roots causing water to enter by osmosis

  3. Plant Environment: Water • From root cells to xylem in roots • Water (and minerals) move between or through cells of cortex • How does water move through plants? • Casparian strips blocks water, force it through membranes of endodermal cells • Endodermal cells selects nutrients that enter xylem

  4. Plant Environment: Water • Xylem is dead, hollow, tubular cells • How does water move through plants?

  5. Plant Environment: Water • From xylem upward to leaves • Water molecules ‘clings’ to xylem and to each other • How does water move through plants? • Water in xylem is unbroken ‘column’ • Water evaporates from leaves ‘pulling’ water up xylem • Evaporative water loss through stomates of leaves is transpiration • 90% of water ‘absorbed’ by roots lost via transpiration in leaves

  6. Plant Environment: Water • Cooling turf or greenhouse (by evaporative cooling) • Frost protection • Other uses of water in horticulture • Modify local environment • Irrigation

  7. Plant Environment: Water • Slight water stress causes stomates to close; photosynthesis reduced • Water deficiency in plants • Reduction in growth • Smaller leaves • Shorter internodes • Smaller plants • Slight water stress can effectively prevent fast, leggy growth

  8. Plant Environment: Water • Severe water deficiency • wilting • Water deficiency in plants • Dry leaf tips or margins • Yellowing of older leaves • Abscission of leaves, flowers, fruit • Same symptoms can occur because of prolonged, excess water

  9. Plant Environment: Water • Container plants • Saturate soil with water; let dry before next watering • Proper watering of plants • Watering completely encourages root growth throughout container • Always use pots with drainage holes • Water until some water trickles out of drainage holes • Overwatering occurs from watering too frequently not too much at one time

  10. Plant Environment: Water • garden plants • Garden plants need regular water • Proper watering of plants • Deficits followed by excess water during particular growth stages reduces quality of vegetable • beans with large air pockets • Ruptures in tomato skin • Growth cracks in carrots

  11. Plant Environment: Water • Soluble salt problems result from: • High levels of salt in soil • Soluble salt problems: • High level of salt in irrigation water • Excessive use of fertilizers • Symptoms include: • Wilting • Drying of tips of margins of leaves • Abscission of leaves, flower, fruit (Symptoms same as lack of water…why?) • Problem solved by flushing plant with water

More Related