The backbreed experiment

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leafminer

Bloody H E L L !
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I started with a 100% sativa and a 100% indica (Aurora).
The idea was first to see what resulted from a 50-50 cross and then to backbreed the cross to the sativa, with the eventual aim of getting back to the original sativa - or near to it - but with the hermie problem fixed.

* The original sativa was completely hermie, probably as a result of many generations of being allowed to grow in large quantities in open country. All the seeds produced plants of male character - bloomed male then produced many 'foxtail' colas so it was self-propagating. The foxtails produced a nice smoke though.

* Progress on the 50-50: I successfully crossed them and have now had a chance to cure and test the smoke and do a direct comparison to the Aurora.
Results:
The smoke is not as potent as the Aurora. Maybe about 70% of the Aurora strength. Several seeds produced identical plants so the 50-50 version seems stable.
It is a more 'up' stone but still didn't possess the 'transcendental' sativa high I was looking for.

* Progress on the 70-30: I have produced some seed and will start it now. I aim to grow several with the aim of producing some third gen seed and start selecting from that.

Overall: this is just an experiment with trash sativa and I don't intend to make the seed available to anyone because I don't think it has good enough characteristics. It's a learning experience. When I understand all this a bit better I will buy some top notch sativa seed and start over.
 
OK, the 70-30's have sprouted and will form part of my outdoor this summer. Now, this grow complies with DJ Short's take on the photoperiod for encouraging sativa genetics. The hermie sativa parent came from about 400 km south of here so I am not far off the same photoperiod.
My first priority is to see if the 70-30's grow into hermaphroditic plants similar to the sativa parent. If I get male and female without hermies this will be a successful step towards recreating the Acapulco Gold strain without the 100% hermie genetics. So this should be an interesting grow.
It looks like the grow is going to be 3 x pure indicas, 4 x 70-30 sat doms, and of course I still have the indica mom. I also have one 50-50 hybrid in flower at the moment so I guess that isn't really part of the 'new' grow.
 
Hey man, sounds real interesting, looking forward to hearing how it turns out. Got any pics to throw up, you know how us stoners like pics :D
 
I thought if you are back breeding you would need a similar Sativa and breed it with your Sativa. Then select the plants that show the traits from your Sativa and back breed it again and again until you get plants that show the traits of the original Sativa. I am by no means a breeder but I will be watching. Did the cross with the Indica shorten your flower time considerably? I have a Mekong Haze in flower right now. She is going on 13 weeks and doesn't even look close to being done.
 
Yes, the 50-50's flowered in 2 more weeks than the pure indicas. I think I harvested at around 9 weeks. The yield was about 40% more than the indica.
Other differences included the dank smell (the indica was pretty much odourless) and the xmas-tree shape with long lower branches.

I'm limited as to what I can do by what I have available. The 70-30 is as far back as I can get in 2 generations. If I have male and female in these, I will get a cross between the 70-30s and then, like DJ Shorts suggests, select from the phenotypes for the most sativa-like ones. The point where I get hermie plants again will mean the experiment fails.

I have to say though, that I found some brown bud from one of the 50-50s last night (from the last harvest; I was in a hurry) and got absolutely fried on it. I tried walking the giant dog in the park and it was like something from a Captain Beefheart album, 'wow look at the red colour of that car ... wow look at the yellow on that one ...' everything very groovy until he saw a French Poodle and I found myself testing Newton's laws.

Best of luck with the haze. Pure sativas ... I grew some in England once in a greenhouse. One grow lasted me the whole year!
 
These 75% sativas look very strange. They look much more like indicas. Short, bushy growth, quite wide leaves. They look more like indicas than the 50-50s do. Weird. What's going on?
Lost the runt. Got destroyed in the grow room collapse.:fid:
 
Do you have any pics of this process you are undertaking? it is a little confusing... Like how are you planning on recreating Acapulco Gold? Is your sativa Acapulco or something?
 
Last pic was of the 5 seedlings:
http://www.marijuanapassion.com/forum/attachment.php?attachmentid=113481&stc=1&thumb=1&d=1242080451

I'll post an update; they are doing well except that I lost the runt in the grow room collapse. Have to put a couple more seeds in to replace that.
The strain is more Oaxaca actually, but pretty close to Acapulco Gold. The idea is to introduce indica genes and then progressively breed back against the pure sativa, with the aim of reproducing the high of the original sativa and also having a non-hermie plant.
The orginal sativas were all bisexual males. No fems at all. Flowering as males and then 2-3 weeks later, covered in cat tails. No use really but the high was very desirable. It's just my way of learning what is / isn't practical. I like the 5050 that I made, it's a good smoke, so I can hardly wait to see what these 75-25's are like.
But if I am interpreting the info from DJ Short correctly, since these are F2s then I should expect a wide variety of genotypes.
I have the feeling though that the indica genes are really dominant! Time will tell. If I can go one more generation I should have 80-20's.
 
Now that they are getting bigger I can see more clearly a whole range of genotypes emerging. One has very round leaves, must have a lot of indica. One has a long distance between internodes, spiky leaves, looks a LOT like the original Mexican sativa. If it is, I will have to see if it reverts to the male/hermie type. If so, reject: experiment fails. Pics soon!
 
I think the experiment has succeeded so far; these are obviously sativas, look the same as the local type that provided the male parent line. Large distance between internodes lower down. Very fast growth, much faster than the indicas.
I lost the runt in the growroom collapse but I've put in three more seeds which are already up, so I have 7 of these sat-doms now.
It's going to be interesting to see what happens. These of course are all outdoor, I expect them to get pretty tall.

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plant3top.jpg


plant4side.jpg


plant4top.jpg
 
Update: the plant on the left is now at 18" tall. The internodes are 5" to 6" apart. I'll have to repot these ASAP.
I am thinking of using 3 gallon hempy buckets, passive hydro (drip nutrient) in the compost (maintain near-constant root temperature - the critical factor in plant happiness, IMO)
 
Thanks leafminer I am thinking about some cross to backbreeding myself. After reading your thread I see I am understanding the backbreeding correctly for keeping the traits I want.
 
As I've said previously, the aim of the backbreed experiment was to reproduce the local sativa, Oaxaca type (not much different from the type grown in Guerrero state known as Acapulco Gold) and in the process, convert it from all males later flowering as females, to male and female versions.

I had been thinking I was a long way towards this result because the current variety is 75% Oaxaca genetics, and the ones that have been growing for two or three weeks are going VERY fast and look just like the male sativas they came from. In fact the tallest is going to 7 lobed leaves I think, and the indica parent never got near 7.

But today I just inspected and what do I see ... could these be female preflowers ... more to the point is the top of this one actually covered in pistils? Looks like it to me, I'd really appreciate YOUR opinion. That plant is 22" tall now.

If it is flowering at 3 weeks - and it hasn't gone alternating node yet, I wouldn't expect it to until it gets to at least 6 feet tall - then what I think this means is that despite the appearance and the fast growth rate (at least 1 1/2" per day, possibly 2" per day), the indica genetics for light cycle vs flowering must be really strongly dominant and the remaining indica component is sending it into flower. :cool:

One more thing:
I checked all four of them. All four are showing female preflowers. The odds against that being random are 16:1 against. I have three more seedlings coming up so if they all turn out female it appears that I have created a feminised 75% sat dom that autoflowers in 13 hour days.

Seriously guys, I am a bit lost here - your input on my reasoning will be welcome.

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Pollen sacs began opening on the male and it is a completely still day today, no wind at the moment; so I have begun to pollinate the BC1 strain, the one I have named "Secret Agent". So the seed will be the first S1 generation from this backbred special.
 
leafminer said:
Pollen sacs began opening on the male and it is a completely still day today, no wind at the moment; so I have begun to pollinate the BC1 strain, the one I have named "Secret Agent". So the seed will be the first S1 generation from this backbred special.

Just to be sure on this: Your S1 is a F2xF2 cross, right? Or, did you back breed it to the sativa?

F2xF2 usually gives some interesting results, but I see that you're trying to get back to a nearly pure sativa.

This will be interesting.

DD
 
i have a d d , sometimers.:) . hey leafminer...

if i am following correctly DD, i will say yes, it seems the S1 is a F2XF2 cross...

are we reading into this correctly leafminer?...Irish...
 
The S1 is indeed backbred to the feral sativa. It went:
Gen 1: 'XX' feral Mexican sativa (blooms first male, then shows fem cattails) used to pollinate best fem Aurora indica. Product: All-fem F1 hybrid seed.
Gen 2: Pollinated the F1s with the same feral sativa. Product: Mostly (80%) fem, S1 seed.
Gen 3: Grew out the S1 and tested. 13 week flowering period. The phenos were quite mixed. One resembled the F1, the others grew to 5ft sat-doms.
No hermies were found despite most of the gene pool being from feral hermie plants.

Conclusions: The strange leaf style found on the S1s is, I assume, caused by inbreeding. The relatively poor yield (3-4 oz) also a result of that, I assume. Potency is excellent however, judging by the test smoke yesterday. If it is as good as I hope fully cured, I may grow it again.
I believe I have at least partly demonstrated that hermie plants don't necessarily result in hermie offspring, also that femmed seed doesn't result in hermie offspring (unless there is bad genetics in there) unlike what some people believe.
 
Good going leafminer! I have a similar back-cross in mind I'll be checkin' with you on in the future, if you have the time bro.
Cheers! Smoke 'em if ya got 'em!
 
It's interesting and you can keep the seed from various experiments in the refri. Let us know what happens with your experiment please!
 

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