Making babies 4 times a year

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British - apparently some US company stole my name
Aug 16, 2017
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Disentangling photoperiod from hop vernalization and dormancy for global production and speed breeding
Bauerle, W.L. Sci Rep 9, 16003 (2019) doi:10.1038/s41598-019-52548-0

"Photoperiod is known to interact with temperature to control flowering in hops. Studies have stipulated that resting dormant buds on hops require a minimum chilling duration for their meristems to break dormancy and grow fruitfully. This assertion, in part, led to a long-held notion that hops require vernalization and/or dormancy for the meristem to change from a vegetative to floral state. The research in this study aims to separate photoperiod from vernalization and dormancy through a series of experiments that artificially control photoperiod to prevent the onset of dormancy and chilling exposure. Six experiments were performed to assess flower yield and quality for seven diverse hop cultivars (with and without exposure to chilling and dormancy) to quantify the impact on flowering performance. Vernalization and dormancy, two plant traits previously considered necessary to the proliferation of hop flowers, do not influence hop flower yield and quality. The findings have broad implications; global hop production can be distributed more widely and it paves the way for speed breeding and controlled-environment production to achieve 4 hop generation cycles per year, as opposed to 1 under field-grown conditions."
I cut my hops back to about 6’ tall in September and they are putting out new bines. Not sure if they are going to do sidearms and flowers, but I figure it’s good for the roots and it’s still 80-freaking degrees F here in SoCal.

Now, though I have hope there may be a second harvest coming. Seeing as how Winter isn’t.
I'll have to look at the details of this story more closely, but I'm rather skeptical of the idea of making 4 generations per year. Even if it were to be possible to get four crops per year, seed viability is typically low at the moment of typical harvest. Seeds need more time. Still, this study clears the way into accelerated breeding.

To remember that a same plant flowering 4 times per year is not the same thing as doing 4 generations per year, though.
Additional interrogation relates to how this all translates to males, which by some sources might have different flowering triggers than females do.