From

Location

Message

Date Posted

Ontario, Canada.

http://extension.oregonstate.edu/mg/botany/hormones.html

Cytokinins also are used to delay aging and death (senescence).

Ethylene is unique in that it is found only in the gaseous form. It induces ripening, causes leaves to droop (epinasty) and drop (abscission), and promotes senescence. Plants often increase ethylene production in response to stress, and ethylene often is found in high concentrations within cells at the end of a plant's life. The increased ethylene in leaf tissue in the fall is part of the reason leaves fall off trees. Ethylene also is used to ripen fruit (e.g., green bananas).


http://www.quickgrow.com/gardening_articles/plant_hormones.html

Cytokinins (such as BA or BAP, or Kinetin, Zeatin): Cytokinins promote cell division, they also promote the growth of lateral buds and stimulate leaf expansion resulting from cell enlargement. Cytokinins also slow down ageing or senescence in leaves, allowing them to stay green and actively photosynthesising for longer.

12/5/2004 11:31:14 AM

Ontario, Canada.

Nitrozyme...Could this work for actively growing fruit.

1985 - 1989 RESEARCH RESULTS (VEGETABLES & FRUIT TREES)
(% of weight increase over non-treated)
Carrots 68% Cabbage 38% Lettuce 44% Peaches 14%
Onions 12% Celery 40% Potatoes 17% Pears 35%
Tomatoes 55% Red Beets

Typical Analysis
A. Active Ingredient

Cytokinin, as kinetin, based on biological activity 0.04% (400 ppm)

12/5/2004 11:45:15 AM

Ontario, Canada.

Sorry here is the link.

http://www.agriorganics.com/products/nitrozyme.html

12/5/2004 11:46:17 AM

yo, i never got back to you on the cytokinins in your first post. cytokinins work with auxin when it comes to lateral shoot development. auxin is produced in the apical meristem of the plant (the growth point) and moves down the plant (yes, things flow backwards in plants, it's not a one way street all you "plant behind the fruit" people) to buds, inhibiting their growth. the auxins basically block the affect of the cytokinins that promote the lateral bud growth. when you prune a plant, you're chopping off the apical meristem and the source of auxin. that allows the affect of the cytokinins to be seen... the lateral buds grow. that's why you get branching when you prune. pretty simple concept, i just tend to offer windy explainations.

cytokinins promote cell division in the presence of auxin. they are found in root tips and young fruit and seeds. they're used in tissue culture (micropropagation) to promote shoot growth.

12/5/2004 12:29:26 PM

Ontario, Canada.

Thanks Brigitte for continued support with the biology. The pumpkin puzzle is coming together nicely. Your explanations are very helpful to all growers concerned about the science aspect of growing AGP's.

12/5/2004 6:27:37 PM

Warwood

Brigitte,
I'm impressed with the Botanical knowledge! You and Nic are helping with the science and hopefully we can all add what we study and experience. I may have to ask more questions before it's growing time. Hope you don't mind. Thanks, Don

12/5/2004 8:00:35 PM

Ontario, Canada.

I wonder how much this would cost to run some testing programs next summer.

Synthetic cytokinin thidiazuron (TDZ). "TDZ remarkably increased fruit growth".

Thidiazuron affects fruit growth, ripening and quality of Actinidia deliciosa
Title
Thidiazuron affects fruit growth, ripening and quality of Actinidia deliciosia

Journal of Horticultural Science and Biotechnology, 74 (3) pp. 375-380, 1999
IS: ISSN
1462-0316
CD: CODEN
JHSBF
NT: Notes
22 refs.
AB: Abstract
The effects of thidiazuron (TDZ) on growth, quality and ripening of kiwifruits were evaluated by comparison with untreated (control) and CPPU (cytokinin) treated fruits. Two weeks after full bloom (AFB), TDZ at 5, 10 or 20 ppm and CPPU at 20 ppm were applied to fruits by dipping them for about 5 s in aqueous solutions of the two compounds. TDZ remarkably increased fruit growth soon after application. The increase in size levelled off at 10 ppm and no further improvement in fruit size resulted from the 20 ppm treatment. At harvest, TDZ treated fruits, depending on the concentration, were 50% or 60% heavier than untreated ones. All TDZ concentrations used also gave a large (+44%) and similar increase in fruit dry weight. TDZ did not cause significant variations in the number and weight of seeds. TDZ caused some modification in fruit shape. It increased the percentage of fruits having a protruded distal end and tended to decrease the fruit length/average diameter ratio, especially at the higher concentrations. TDZ caused an increase in the size of all the tissues of the fruits without changing their relative proportions at harvest. TDZ treated fruits had an advanced and/or faster ripening (about one week) with respect to the control. In general, results of CPPU were similar to those of TDZ treated fruits at the same concentration (20 ppm). TDZ greatly stimulates fruit growth indicating that it can be a powerful tool for improving kiwifruit cropping.

12/5/2004 8:04:33 PM

Appalachian Mtns.

Used PGR, no visible differences, won't try it again.

12/6/2004 6:55:15 AM