Experimenting with Light/Dark Hours

[Delta 9]

Found a good article from DJ Short (Guru breeder) on how light effects the different geno and phenotypes

 

 

To understand the principles behind the breeding of cannabis you first need to be familiar with some basic terms related to genetics. "Genotype" is the genetic and chromosomal make-up of any given individual ? it is the genetic code. "Phenotype" is the expression of body type, structure, and appearance of individuals; it results from the interaction between genotype and environment.

Specific environmental conditions are often required for certain phenotypic expressions from a given genotype. If the available nutrients, hours of sunlight, or other conditions are not available then the development of the plant or animal will be altered. These conditions are referred to as "environmental triggers."

 

Two individuals with the same genotype can have greatly different phenotypes if grown in different environments.

 

Indoor vs outdoor

 

In terms of growing and breeding cannabis, there is a distinct difference between indoor and outdoor grow environments. No matter where on the planet one is, the indoor environment is usually far more limited when compared to the spectrum of conditions existing outdoors.

 

When compared to the wide variety of conditions available outdoors, the indoor environment may be seen as relatively bland and generic. The greenhouse environment, especially when fortified with electric light, is perhaps the closest thing available to a happy marriage between the two.

 

http://www.cannabisculture.com/library/images/uploads/2600-sprouts.jpgThree subspecies

 

It is useful to agree, at least in theory, that there are three separate subspecies of the genus Cannabis ? Sativa, Indica and Ruderalis.

 

Advertisement

Cannabis Sativa is the equatorial variety found primarily around 30 degrees latitude North or South. Sativa generally grow tall, from seven to thirty feet, have many long branches, narrower leaflets, and mature slowly.

 

Cannabis Indica varieties generally inhabit the areas between 30-50 degrees North or South latitude. Indica are generally much shorter than Sativa, only about three to five feet tall. They have fewer and shorter branches than Sativa, the longer of which are lower on the plant, with much wider leaflets. They also mature earlier and more rapidly than Sativa.

 

Cannabis Ruderalis grow naturally primarily past 50 degrees north latitude (the Siberian steppes). Ruderalis are the shortest, least bushy, and fastest maturing of the three.

 

http://www.cannabisculture.com/library/images/uploads/2600-sativa-planttop.jpgThe end of the sweet spots

 

Prior to the late 1970's, virtually all commercially available cannabis products came from the great outdoors. Many of these varieties had been grown in their particular region since antiquity ? not since the advent of sailing had a greater diversification and distribution of the herb occurred.

 

Most cannabis available was also very well acclimated to its particular region of origin. Certain places tended to produce very unique and desirable types of herb that were renowned to each region. I like to refer to these high-quality cannabis producing areas as "sweet spots." The products coming out of these sweet spots during this era were among the finest herbs ever available.

 

A series of phenomena occurred in the late 1970's and early 80's that has since revolutionized the cannabis industry. This series included the triad of sinsemilla, High Intensity Discharge (HID) lighting, and the introduction of Indica genetics, coupled with draconian herb laws that drove the industry far underground. Never before in human history was so much genetic diversity of cannabis grown in such generic, indoor conditions. The results of this phenomenon have wreaked havoc on the cannabis gene pool.

 

http://www.cannabisculture.com/library/images/uploads/2600-indoor-grow.jpgThe road to blandness

 

As Indica, sinsemilla and HID lighting became predominant, it became apparent that Sativa varieties were very difficult to coax commercial amounts of sinsemilla herb from indoors. The fast maturing, dense bud structure of the easy-to-grow Indica soon dominated the indoor grow scene.

 

Another factor contributing to the desirability of the indoor Indica was its truebreeding "dioecious" nature, meaning that individual plants tend to be male or female only, but not both. In contrast, many Sativa strains show hermaphroditic tendencies indoors, with male and female flowers on the same plant. (It is my opinion that wild Sativa strains of cannabis are primarily truebreeding hermaphroditic varieties.)

 

As outdoor production diminished due to intolerant laws and the drug war, indoor production of Indica phenotypes became the staple of the commercial indoor grower. The road to generic blandness had begun.

 

Although some Sativa/Indica crosses matched some of the Sativa flavor and head high with the Indica bud structure, this desirability would only last for a few generations of breeding. Unless a person is breeding for a very specific trait, crosses seven generations and beyond the original P1 Indica/Sativa cross lose much of their original charm and desirability. Cloning, however, helps to extend a given plant's potential.

 

http://www.cannabisculture.com/library/images/uploads/2600-indicaplantbottom.jpgRuderalis: myth and misnomer

 

As indoor growers attempted to improve their genetic lines via breeding, another interesting phenomenon occurred: Ruderalis. Although there is a wild variety identified as Ruderalis in Russia ("Ruderalis" is supposedly Russian for "by the side of the road") that grows very short and matures very fast, I seriously doubt the rumor that someone actually went to Russia to collect seeds of this variety sometime in the past. Or, if someone actually did go all the way to Russia to find, collect and smuggle "rudy" seeds, I do feel sorry for their waste of time. They could have gotten the same worthless thing from Minnesota, Saskatchewan or Manitoba with much less hassle.

 

The North American Ruderalis probably originated as follows: After the Indica varieties arrived in the US and became incorporated into the gene pool, many breeders began to cross the earliest maturing individuals with each other in hopes of shortening the maturation cycle.

 

It would only take a few generations for the ugly Rudy phenotypes to begin expressing themselves. By ugly, I am referring to a strong lack of potency and/or desirability. I know, I was once guilty of the practice myself. It did not take me long to realize that this was a huge mistake in regard to the quality and potency of the future generations' finished product, and all subsequent breeding along this line was ceased.

 

Many of these manipulated rudies were released on the open market between 1981 and 1986. It was shortly after this period that the grow journals of the era (Sinsemilla Tips and High Times) ran articles about the possibility of a new wonder variety for indoor grows: fast blooming Ruderalis. Rumor had spread to myth and misnomer. Therefore, it may be more appropriate to say that the Ruderalis phenotype was coaxed from Indica genetics, via the indoor breeding environment.

 

The same applies to many of the Indica dominant varieties available today. Breeders selecting for early, fast flowering or fast growth often miss out on some of the finer and more subtle characteristics available from crossing certain genotypes. My advice to breeders is to wait until the finished product is suitably tested before coming to any conclusions regarding desirable candidates for future breeding consideration.

 

http://www.cannabisculture.com/library/images/uploads/2600-buds_shots.jpgPhenotypic expression

 

The malleability of phenotypic expression among the Sativa/Indica crosses must also be noted. The variability of phenotypic expression among the f2 generation of a truly polar (pure Sativa/pure Indica) P1 cross is quite phenomenal. The second generation f2 crosses will exhibit the full spectrum of possibilities between the original parents ? extreme Indica, extreme Sativa, and everything in between.

 

However, regardless of any particular phenotype selected from among this given f2 cross, future generations may drift radically. Depending on the presence (or lack) of a number of environmental triggers, an f2 Indica phenotype may be coaxed more toward Sativa traits, or an f2 Sativa phenotype may be coaxed more toward Indica expression. The key is environmental conditions.

 

This is what distinguishes the truebreeding, ancient acclimated, region of origin varieties ? especially the tropical and equatorial Sativa ? from the crosses that have happened since. The ancient specimens have a much narrower genotype range, and therefore a more specific phenotype than their contemporary crosses despite environmental conditions. It is up to future adventurers to provide the best possible environmental considerations, along with the best possible genetic considerations, in order to resurrect the legendary happy flowers of yore.

 

http://www.cannabisculture.com/library/images/uploads/2600-breeding-tips-chart.jpgInducing Sativa

 

After many years of first-hand experience breeding herb indoors as well as outdoors, I am of the opinion that the two most influential factors involving phenotypic variation and expression among current indoor herb breeding projects are the photoperiod (hours of light per day) and the angle of light in relationship to the growing plant.

 

Specifically, I find the single most powerful influence to the Indica dominant phenotype is the traditional 18/6 veggie cycle and 12/12 flowering cycle. The 18/6 veggie and 12/12 flower cycle is an attempt, however poor, to mimic the Indica-producing photoperiod. It is my belief that this light cycle strongly influences for Indica phenotypic expression.

 

Sativa phenotype characteristics will manifest under a more equatorial photoperiod, closer to a 13/11 veggie cycle and an 11/13 flower cycle. This is the light timing range to use to elicit more Sativa dominant expression from your plants.

 

As for the exact photoperiod formula that I incorporate into my growing/breeding regime, this will presently remain a trade secret. My advice is to experiment with different photoperiods, keep good notes and pay attention. Avoid the 18/6 and 12/12 photoperiods, while tweaking the times a bit differently with each breeding cycle until more desirable results in the finished product and their offspring are noted. Here's a hint: work in half-hour increments or a little less, and good luck!

 

http://www.cannabisculture.com/library/images/uploads/2600-indica-sativa-leaves.jpgIndica and Sativa characteristics.Angle of Light

 

Angle of light simply refers to the physical angle of light source the plant is dependent upon for growth. Perhaps the greatest difference between indoor and outdoor environments has to do with the angle of light received by the plant. This is also one of the greatest seasonal differences between the Sativa and Indica producing regions.

 

Outdoors, the main light source is the Sun, with minor influence coming from nearby reflective surfaces. As a plant grows taller and broader outdoors, that angle of light from the sun changes very little in relationship to the growing plant.

 

Seasonal changes in angle of light increase the further away from the equator one gets. At the equator there is the least amount of seasonal change in angle of light, only about 20?, whereas at the 45th parallel that change is as great as 45?. At the 45th latitude, the Summer Sun is high in the sky while during early Spring and late Fall the sunlight comes from much lower in the sky. The farther one goes from the equator, the greater the difference in seasonal changes regarding angle of light.

 

Indoors, the lights typically range from a few inches to several feet from the plant. As the plant grows taller, its physical relationship to the bulb's angle of light changes considerably. Most indoor grow rooms have relatively low ceilings, therefore, raising the bulbs may maintain a similar angle of light early on, but eventually the angle changes. The same differences may be noted among plants directly below the bulb and the plants off to the side of the room farther away from the bulb.

 

Circular light shuttles tend to emulate the arctic summer and create a confusing signal completely unknown to the equatorial Sativa. Straight-track overhead light shuttles are more conducive to inducing the Sativa phenotype.

 

http://www.cannabisculture.com/library/images/uploads/2600-Blueberry_Durban-Cross.jpgBlueberry x Durban PoisonAromatics and flavors

 

Many indoor growers try to get their budding plants as close to the light source as possible. Though this may increase bulk production of both bud and trichome, I find that this practice tends to destroy many of the finer aromatic qualities of the herb.

 

Buds too close to the light tend to express nothing beyond the lower lemon/lime aromas of the fruity spectrum. Sometimes the aroma is no better than a strong chemical/astringent odor and flavor, especially those under High Pressure Sodium light systems. The finer berry flavors tend to favor more distance from the bulb, and will manifest more strongly under High Ultraviolet Metal Halide light systems, especially during the latter stages of flowering.

 

Something akin to a gymnasium building with high ceilings and super 5000W lights hung far from the growing plants, set at a Sativa-tweaked photoperiod, would be the ultimate indoor grow-op to coax Sativa phenotypes.

 

Sweet spot fantasy

 

Nothing will ever rival the great outdoor sweet spots for quality cannabis production. Hopefully, someday, somewhere, someone will be daring and lucky enough to get away with re-establishing some of the great genetic lines in their specific region of origin sweet spots.

 

Equatorial Sativa varieties are of interest for quality herb production (Thailand, Oaxaca, Colombia, Central Africa, etc.) as the Indica zones are more renowned for hashish production. Parts of Nepal tend to produce both excellent hashish and fine Sativa buds, with some plants reportedly living longer than two years!

 

I hope that I am able to live long enough to once again experience the joy associated with the fine herbal products from the great regional sweet spots of near ancient lore. It has been a long time and I am looking forward to the day.

 

 

http://www.cannabisculture.com/articles/2600.html

[Frazz]

excellent research and info in those two posts Delta9

 

[R.H.Goddard]

Well if you thought 12/1 is an odd photo-period, how about 21:36/12? to increase yield during max flowering rate? I've seen this posted everywhere while searching for reliable info about photo-periods, though really while I'm not saying it's all false I'm certainly not posting this for anything other than entertainment purposes at this stage

 

 

The only photoperiod manipulation from years of experiments that offered discernible improvements was this adjustment made for 1 or 2 calendar weeks at the point of maximum flowering rate: Daylength of 21 hours, 36 minutes with a dark period of 12 hours. To accomplish this, you need a 7 day, 24 hour digital timer. During a 7 day calendar week on Earth, the "sun" only cycles 5 times. This permits easily switching back to the regular 12/12 at your discretion. You may want to only alter during peak flower production to stimulate the plant's metabolism. Using this photoperiod throughout the flowering cycle will cause this:

 

A variety that takes 49 days of 12/12 to mature, won't see 49 - 12 hour dark periods under 21:36/12 until almost 10 calendar weeks have passed.

 

The total increase in light energy is almost 80%, which will produce larger yields, if all of your other enviromental conditions are kept optimal.

 

The total increase in flowering period is only 40%, half the potential room for improvement. This means you don't have to be perfect to win out.

 

Selective application of the 21:36/12 photperiod for only 1 or 2 weeks extends the wait only 2 to 4 Earth days, which makes up the missing 2 complete day and night cycles each week on Planet Ito. This permits the additional light energy to be provided without purchasing additional equipment or overloading existing circuits, which maximizes the existing system's capabilities. The main advantage is that matched with co2 and optimal nutrition, the plants metabolism will increase dramatically. I have only successfully tested this photoperiod for two weeks. The potential for a net increase of 40% over the entire cycle (80% increase in light energy vs. 40% longer wait) is worthwhile. Don't be afraid!

 

Day 1 - Sunday, 6:00am til Monday, 3:36am

Day 2 - Monday, 3:36pm til Tuesday, 1:12pm

Day 3 - Wednesday, 1:12am til Wednesday, 10:48pm

Day 4 - Thursday, 10:48am til Friday 8:24am

Day 5 - Friday, 8:24pm til Saturday 6:00pm

 

Author: MisterIto

 

Source: http://www.420magazi...ger-yields.html

 

 

Again, "from years of experiments...". Where the hell are these experiments? Why would somebody take the time to do years of experiments, and not even publish anything about the methodology let alone a a slightly detailed analysis of the results? That said they don't exactly even imply what it's going to do, just that it'll "increase yield".

 

Might be possible to find more info somewhere... Anyone care to try? .

[The Claw]

Very interesting thread, will look at it. Another thread posted by D9 is well worth a look, here is a short snipbit from DJ Short (Guru breeder) has been around forever like Ed, has recently come out of hiding so to speak and now gives sold out seminars on growing lives in Oregon. Google him.

 

After many years of first-hand experience breeding herb indoors as well as outdoors, I am of the opinion that the two most influential factors involving phenotypic variation and expression among current indoor herb breeding projects are the photoperiod (hours of light per day) and the angle of light in relationship to the growing plant.

 

Specifically, I find the single most powerful influence to the Indica dominant phenotype is the traditional 18/6 veggie cycle and 12/12 flowering cycle. The 18/6 veggie and 12/12 flower cycle is an attempt, however poor, to mimic the Indica-producing photoperiod. It is my belief that this light cycle strongly influences for Indica phenotypic expression.

 

Sativa phenotype characteristics will manifest under a more equatorial photoperiod, closer to a 13/11 veggie cycle and an 11/13 flower cycle. This is the light timing range to use to elicit more Sativa dominant expression from your plants.

 

As for the exact photoperiod formula that I incorporate into my growing/breeding regime, this will presently remain a trade secret. My advice is to experiment with different photoperiods, keep good notes and pay attention. Avoid the 18/6 and 12/12 photoperiods, while tweaking the times a bit differently with each breeding cycle until more desirable results in the finished product and their offspring are noted. Here's a hint: work in half-hour increments or a little less, and good luck!

 

Read this article by DJ Short, very informative http://www.cannabisc...icles/2600.html

 

Vrod.

[R.H.Goddard]

The previous post I find somewhat odd in certain respects, e.g. where did the level of precision come from (36 min?)), just posted for anyone interested.

 

Also does the link you posted only not work for me? My browser says unable to connect; I found the article anyway here :

http://www.mrnice.nl/forum/5-strain-base/4000-dj-short-photoperiod-angle-light.html

(in case other doesn't work for others)

 

My advice is to experiment with different photoperiods, keep good notes and pay attention.

That I definitely agree with and probably above all would encourage people to experiment as scientifically (e.g. controls!) as possible, make as detailed observations as possible and above all publish/distribute the results for examination/discussion!!!

 

I don't think anyone really can argue with someone else's observations. If someone else says "I tried 24/0 and 18/6 plenty times over the years and found no difference", you can't really argue with it due to the lack of detail; if that's what they see, that's what they see. However if they would describe exactly how the test was done, detail the methodology, even better-include pics etc. etc. the validity and reliability of their conclusions can in that case be argued as their observations could have been a result of some experimental flaws...

 

If only the retarded laws would change so greater/unrestricted research could be done...

 

 

Anyway, when I can finally set up and get growing with a 600 mh/hps and get a few plants done, perhaps some time coming year I may be able to do a couple identical set ups and do some tests. I still haven't been able to find any detailed experiments comparing photo-periods...

Right now all I have is 200W of cfl's with an auto-flower underneath slowly struggling along (looks reasonable though I think).

 

Will get there eventually.

[El Gato]

I have heard of 18/12 for veg and 12/12 for flower working very well. If I had a timer that could do that I would try.

[R.H.Goddard]

Who's been screwing with my posts? I'm joking. Was a bit off topic in the other thread, though instead of a new thread I think this could actually be merged with Frazz's Cannabis under Different Lighting Regimes

 

Some interesting posts & observations in there already regarding photo-periods, and if anyone would do a new experiment they'd better do a grow diary

[STONEDAJ69]

You sure about that there 18/12?

[MongyMan]

............instead of a new thread I think this could actually be merged with Frazz's Cannabis under Different Lighting Regimes

 

Done....

 

 

Peace MongyMan

[El Gato]

yes aj. 30 hr day...