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CUTTINGS
    
Cutting - a plant part that when removed from the parent plant and placed under theproper
              environmental conditions forms adventitious roots and/or shoots.

HOW TO MINIMIZE WATER LOSS IN CUTTINGS?
1) Place cuttings in cool, humid area - for leafless cuttings

2) Spray cuttings with antitranspirants

    antitranspirants - chemicals that decrease transpiration by forming a film on the leaf surface or
                                by physiologically closing stomata.

3) Place cuttings in a humidity chamber - enclosed chamber with very high humidity.

4) Place cuttings under an intermittent mist system.

    Intermittent Mist System
    A propagation system that periodically (every 5 to 30 minutes) sprays a fine mist of water on the cuttings to keep the foliage moist and minimize water loss.

    Effective due to:
    a) high relative humidity
    b) cooler temperature
    c) allows use of higher light intensity
    d) increases endogenous root promoting substances
    e) may decrease disease

    Disadvantage
    leaching - the loss of nutrients and other compounds from inside leaves and stems.
    During intermittent mist propagation up to half of some of the nutrients in the leaf can be leached out.  This causes the cuttings to be nutrient deficient.  The problem can be corrected with nutrient mist.
     

      nutrient mist - addition of dilute fertilizers to the mist; replaces nutrients lost to leaching.  Use 2-6 oz. of a 20-20-20 or equivalent soluble fertilizer per 100 gallons of water.


HORMONES USED ON CUTTINGS
1) auxin - stimulates adventitious root formation on stem cuttings.
              - IBA (most commonly used), NAA (frequently used), 2, 4-D (less used).
2) cytokinin - stimulates adventitious shoot formation on leaf or root cuttings.
                    - kinetin (commonly used), benzyladenine (BA) (commonly used), zeatin (seldom used),
                      pyranylbenzyladenine(PBA) ( used in research).