I will start by citing two studies:
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H. L. SHEPHARD, J. S. PARKER, P. DARBY and C. C. AINSWORTH. Sexual
development and sex chromosomes in hop. New Phytol. (2000), 148, 397-411
"The switch from vegetative to reproductive development in female hop plants is triggered by shortening daylength (Tournois, 1912; Thomas & Schwabe, 1969). The critical daylength is genotype-dependent, although plants of both sexes must initiate a minimum number of nodes before flowering can be induced (e.g. 30-32 for the variety `Fuggle' ; Thomas & Schwabe, 1969). The influence of daylength on floral induction in male hop plants is less clear. Once these conditions and certain other environmental factors such as temperature are met, the plant switches from the vegetative to the reproductive phase."
And:
Factors Controlling Flowering in the Hop (Humulus lupulus L.)
G. G. THOMAS and W. W. SCHWABE
"In experiments on the effects of daylength on the growth and flowering of the perennial hop it was shown that Humulus lupulus is a short-day plant. The absolute length of the short day is important since very short days (8h) induce dormancy before flowering can occur. Light-break treatment may therefore promote or inhibit flowering according to the associated main photoperiod. A minimum node number must have been differentiated before the hop can be induced to initiate flowers, an effect analogous to the juvenile condition. Minimum leaf number and critical daylength for induction depend on variety. At low temperature, induction is possible with longer photoperiods. Promotion of flowers by growth retardants (B9 and CCC) in unfavourable daylengths, and delay of initiation by gibberellic acid treatment were also observed."
And:
Effects of Plant Growth Regulators on Growth and Reproduction of Humulus lupulus
Newton Chad Rowland, Tennessee State University
"Traditionally, in the US, hops are grown in the field in northern latitudes without the use of plant growth regulators (PGR). This research was to find out if the use of PGR could sufficiently reduce the height of hop vines to allow them to be grown in a greenhouse and produce similar flower yield of those grown in the field at northern latitudes. The hop cultivar Cascade was chosen for this study after it was compared in a preliminary trial with 'Perle', 'Fuggle' and 'Magnum'. In that initial trial, 'Cascade' produced the highest yield and appeared to be better adapted for growth under greenhouse environments using hydroponics. Of the four PGR's (Sumagic, Cycocel, B-9, and A-Rest) evaluated, only Sumagic had any effect on reducing vine length. Treatments that yielded the highest reduction in vine length (325 cm) was Treatment #1 (5 ppm) of Sumagic. Application of Sumagic slightly affected the average wet flower weight from 259, 226.5, 324, 284, and 282.5 grams from 5ppm to 0ppm, respectively. The first internode measurements had average lengths of 3.25, 7.75, 12.25, 14.5, and 18.25 centimeters 5.0 ppm to 0.0 ppm, respectively. Each Treatment yielded results that were significantly different from each other. All vine length reductions were significantly different. Treatments #1 (5 ppm), #2 (2.50 ppm), and #4 (0 .62 ppm) yielded had average lengths of 421.06, 417.44, and 430.00 centimeters respectively. Wet flower yield were 104.88, 251.50, 217.75, 257.38, and 213.75 grams from 5ppm to 0ppm, respectively. The first internode measurements produced average lengths of 3.62, 6.88, 10.50, 15.19, and 18.44 centimeters from 5.0 ppm to lowest 0.0 ppm of PGR. Results of the second experiment yielded similar results for vine reduction and flower yield."
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Now, the reason I am bringing these studies and this concept to your attention is for those wishing to breed hops from seeds. It seems I will soon have to do the same and I realized what a waste of time and resources it will be to grow 100 seeds and keep just a few plants. The solution to the dilemma seemed obvious:
I would have to eliminate the undesirables as quickly as possible before they consumed too much space and time... But, to know what plants were desirable, I would need flowers. And, to have flowers before the plants consumed space meant I would need to manipulate their natural growth.
Here is my treatise:
1. Start with as large a selection of seeds as possible and plant them in containers that can easily be brought indoors.
2. Spray a gibberellin inhibitor like Sumagic® regularly after the plants have passed the seedling stage to keep them dwarfed.
3. Upon reaching a safe 40 nodes, switch to a 12/12 light cycle by leaving the plants outdoors, during the day and in the sun, for twelve hours and then bringing them inside to a cool dark place like a cellar or basement for twelve hours.
4. When plants begin to flower, analyze all of your plants and cull the undesirables.
5. Switch to an 8/16 hour cycle to induce dormancy in remaining plants.
6. After a small dormant period, bring plants back outside and let them finish the season.
7. Have a beer.
The main reason for this treatise is for space concerns when trying to breed new varieties on a small scale. Growing hundreds of unreliable plants would normally be outside of the reach of a small hobbyist, but maybe with this methodology, it is slightly more doable.
Also, I assume the plants would reach 40 internodes much quicker when the space between each node is about 1/5th of what it would otherwise be.
I welcome all feedback.
----------------------------------------------------------------------
H. L. SHEPHARD, J. S. PARKER, P. DARBY and C. C. AINSWORTH. Sexual
development and sex chromosomes in hop. New Phytol. (2000), 148, 397-411
"The switch from vegetative to reproductive development in female hop plants is triggered by shortening daylength (Tournois, 1912; Thomas & Schwabe, 1969). The critical daylength is genotype-dependent, although plants of both sexes must initiate a minimum number of nodes before flowering can be induced (e.g. 30-32 for the variety `Fuggle' ; Thomas & Schwabe, 1969). The influence of daylength on floral induction in male hop plants is less clear. Once these conditions and certain other environmental factors such as temperature are met, the plant switches from the vegetative to the reproductive phase."
And:
Factors Controlling Flowering in the Hop (Humulus lupulus L.)
G. G. THOMAS and W. W. SCHWABE
"In experiments on the effects of daylength on the growth and flowering of the perennial hop it was shown that Humulus lupulus is a short-day plant. The absolute length of the short day is important since very short days (8h) induce dormancy before flowering can occur. Light-break treatment may therefore promote or inhibit flowering according to the associated main photoperiod. A minimum node number must have been differentiated before the hop can be induced to initiate flowers, an effect analogous to the juvenile condition. Minimum leaf number and critical daylength for induction depend on variety. At low temperature, induction is possible with longer photoperiods. Promotion of flowers by growth retardants (B9 and CCC) in unfavourable daylengths, and delay of initiation by gibberellic acid treatment were also observed."
And:
Effects of Plant Growth Regulators on Growth and Reproduction of Humulus lupulus
Newton Chad Rowland, Tennessee State University
"Traditionally, in the US, hops are grown in the field in northern latitudes without the use of plant growth regulators (PGR). This research was to find out if the use of PGR could sufficiently reduce the height of hop vines to allow them to be grown in a greenhouse and produce similar flower yield of those grown in the field at northern latitudes. The hop cultivar Cascade was chosen for this study after it was compared in a preliminary trial with 'Perle', 'Fuggle' and 'Magnum'. In that initial trial, 'Cascade' produced the highest yield and appeared to be better adapted for growth under greenhouse environments using hydroponics. Of the four PGR's (Sumagic, Cycocel, B-9, and A-Rest) evaluated, only Sumagic had any effect on reducing vine length. Treatments that yielded the highest reduction in vine length (325 cm) was Treatment #1 (5 ppm) of Sumagic. Application of Sumagic slightly affected the average wet flower weight from 259, 226.5, 324, 284, and 282.5 grams from 5ppm to 0ppm, respectively. The first internode measurements had average lengths of 3.25, 7.75, 12.25, 14.5, and 18.25 centimeters 5.0 ppm to 0.0 ppm, respectively. Each Treatment yielded results that were significantly different from each other. All vine length reductions were significantly different. Treatments #1 (5 ppm), #2 (2.50 ppm), and #4 (0 .62 ppm) yielded had average lengths of 421.06, 417.44, and 430.00 centimeters respectively. Wet flower yield were 104.88, 251.50, 217.75, 257.38, and 213.75 grams from 5ppm to 0ppm, respectively. The first internode measurements produced average lengths of 3.62, 6.88, 10.50, 15.19, and 18.44 centimeters from 5.0 ppm to lowest 0.0 ppm of PGR. Results of the second experiment yielded similar results for vine reduction and flower yield."
----------------------------------------------------------------------
Now, the reason I am bringing these studies and this concept to your attention is for those wishing to breed hops from seeds. It seems I will soon have to do the same and I realized what a waste of time and resources it will be to grow 100 seeds and keep just a few plants. The solution to the dilemma seemed obvious:
I would have to eliminate the undesirables as quickly as possible before they consumed too much space and time... But, to know what plants were desirable, I would need flowers. And, to have flowers before the plants consumed space meant I would need to manipulate their natural growth.
Here is my treatise:
1. Start with as large a selection of seeds as possible and plant them in containers that can easily be brought indoors.
2. Spray a gibberellin inhibitor like Sumagic® regularly after the plants have passed the seedling stage to keep them dwarfed.
3. Upon reaching a safe 40 nodes, switch to a 12/12 light cycle by leaving the plants outdoors, during the day and in the sun, for twelve hours and then bringing them inside to a cool dark place like a cellar or basement for twelve hours.
4. When plants begin to flower, analyze all of your plants and cull the undesirables.
5. Switch to an 8/16 hour cycle to induce dormancy in remaining plants.
6. After a small dormant period, bring plants back outside and let them finish the season.
7. Have a beer.
The main reason for this treatise is for space concerns when trying to breed new varieties on a small scale. Growing hundreds of unreliable plants would normally be outside of the reach of a small hobbyist, but maybe with this methodology, it is slightly more doable.
Also, I assume the plants would reach 40 internodes much quicker when the space between each node is about 1/5th of what it would otherwise be.
I welcome all feedback.