Japanese hops x Ruderalis
- Thread starter Thule
- Start date
What's up bro? I'm going to be looking what happens with that... I've always been curious on Hops plants. I'm going to try to gather a few seeds. My region used to be a hop producer many decades ago, they are trying to push it again using hop heirlooms and developing new strains with unique qualities for beer making.
Vibes.
Vibes.
Interesting, Thule. Is this just a botanical experiment or do you have some practical objective in mind?
I have a couple of Oregon hops vines that have been growing for more than 20 years and, even though supposedly a close relative of Cannabis, I cannot see anything in them remotely similar to Cannabis.
I have a couple of Oregon hops vines that have been growing for more than 20 years and, even though supposedly a close relative of Cannabis, I cannot see anything in them remotely similar to Cannabis.
Hola Musta, same ol' same ol', but took some effort to get the motivation back. You've probably got humulus lupulus growing there, humulus japonicus is closer to cannabis in the family tree so there's at least a theoretical chance of seeds here. Well see how it goes.
I have to be realistic, if the crossing was easy to achieve I think we'd see a lot more true hybrids out there, so far there are no confirmed crosses that I'm aware of. Webbed strains are a possible hint though. I have no aims other than to see if it's possible. I did however pick the most likely parents for the experiment as according a Chinese study ruderalis strains show signs of introgression from humulus japonicus so they might be closer to each other genetically than one might assume.
I've pollinated cannabis with japanese hops before, but I always seem to get busted before I can make any conclusions. I remember having immature aborted seeds on the plants but I had all kinds of pollen flying around at the time.
Although a climbing cannabis strain would be nice I'm not sure if I'd have any practical use for such a cross. Japonicus doesn't have a perennial root system and is rather slow flowering so nothing to gain there. I do however believe that the species have interbred in the very distant past and given rise to the subspecies Cannabis sativa, that's where traits such as red branchless stalks and purple pistils might originate from..
I actually have a whole bunch of weird hops/canna hybrids. They are out there.
There is this one german guy, goes by the name of Kaly Seeds based in Spain, also sells his seeds online. His seeds are are mostly dutch stuff crossed with the outcome of his grafting experiments as far as i understand. No affiliation by the way.
I grew out a few seeds of his earlier stuff. Most plants have different kinds of ducksfootesque Webbing.
I sometimes get a red spot here and there if the tip of a leaf of a regular plant pokes my skin, but those hops hybrids gave me something closer to allergic reactions. If i would reach my naked arm in a bush of these, somebody taking a look at my arms might just think i just ran through a stinging nettle patch :X. Some of the plants are pretty good smoke, although really weird and unusual effect. There is something strange going on biochemically.
Anyone interested in getting something from kaly, I'd recommend the SWAG or SWAG Afghan (stupid names), these are the ones I've found worth keeping anyway. Completely webbed plants staying that way while flowering are pretty stealthy after all.
@ Mustafunk
As far as I know Thule is right, japanese Hops is the one to get.
Anyway just my two cents.
There is this one german guy, goes by the name of Kaly Seeds based in Spain, also sells his seeds online. His seeds are are mostly dutch stuff crossed with the outcome of his grafting experiments as far as i understand. No affiliation by the way.
I grew out a few seeds of his earlier stuff. Most plants have different kinds of ducksfootesque Webbing.
I sometimes get a red spot here and there if the tip of a leaf of a regular plant pokes my skin, but those hops hybrids gave me something closer to allergic reactions. If i would reach my naked arm in a bush of these, somebody taking a look at my arms might just think i just ran through a stinging nettle patch :X. Some of the plants are pretty good smoke, although really weird and unusual effect. There is something strange going on biochemically.
Anyone interested in getting something from kaly, I'd recommend the SWAG or SWAG Afghan (stupid names), these are the ones I've found worth keeping anyway. Completely webbed plants staying that way while flowering are pretty stealthy after all.
@ Mustafunk
As far as I know Thule is right, japanese Hops is the one to get.
Anyway just my two cents.
Thanks for the feedback! I've seen pictures of Kaly seeds strains and that's why I mentioned the webbing. Who knows, ducksfood could be the result of such a cross. Kaly seeds wasn't very specific on the details of the alleged cross so that's why I remain sceptical. As far as I remember they used a japonicus male on a kush plant.
Well he was on some German Boards... Very deatiled Reports of his works.. sadly he got banned for his bad karma he also got...
But there was alot of detailed things from him!
You're welcome. Yeah there has been a lot of scepticism regarding canna/hops hybrids for the longest time. I was somewhat sceptical too, but I chatted with him for a while and he let me download his Dropbox archive which included several hundred pictures including intermediate breeding steps so i buy his story.
But then again, you can only know if you did it yourself. If his seeds are not hops hybrids, he sure knows how to make webbed cannabis, for whatever that's worth.
But then again, you can only know if you did it yourself. If his seeds are not hops hybrids, he sure knows how to make webbed cannabis, for whatever that's worth.
Hello Thule 
,
it is a nice experiment to try crossing Humulus japonicus to Cannabis sativa.
I think I've read in R.C. Clarke's book " Cannabis Evolution and Ethnobotany " that reseachers had sometimes quite problems to distinguish hop pollen from Cannabis pollen when examining ancient lake sediments to know if Cannabis was distributed in a certain area at a certain time altough I do not know specifically about H. japonicus.
Just trying to say that Humulus and Cannabis pollen grains aren't morphologically too different from each other so a crossing might be possible.
Would be also interesting to know if Cannabis and H. japonicus have the same number of chromosomes.
If not, the F1 probably would not be fertile if seeds develope and germinate ...
I also grew the variety " Pintura Ruderalis " by Kaly Seeds last year and got some strange looking plants and kept the biggest and most vigorous female together with one male and gifted the rest to friends.
Please ignore the date of the photos, it is somehow wrong, the plants were grown in 2014.
Cheers
, it is a nice experiment to try crossing Humulus japonicus to Cannabis sativa.
I think I've read in R.C. Clarke's book " Cannabis Evolution and Ethnobotany " that reseachers had sometimes quite problems to distinguish hop pollen from Cannabis pollen when examining ancient lake sediments to know if Cannabis was distributed in a certain area at a certain time altough I do not know specifically about H. japonicus.
Just trying to say that Humulus and Cannabis pollen grains aren't morphologically too different from each other so a crossing might be possible.
Would be also interesting to know if Cannabis and H. japonicus have the same number of chromosomes.
If not, the F1 probably would not be fertile if seeds develope and germinate ...
I also grew the variety " Pintura Ruderalis " by Kaly Seeds last year and got some strange looking plants and kept the biggest and most vigorous female together with one male and gifted the rest to friends.
Please ignore the date of the photos, it is somehow wrong, the plants were grown in 2014.
Cheers
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Cannabliss420
Member
how interesting! im going to keep watch on this thread 
@ngakpa
When i first discovered this topic I've pondered the longest time over the idea if this might be something like naturally occuring protoplast fusion. In the lab they use bacteria from the genus Agrobacterium to transfer genes into plants. Maybe some species capable of gene transfer occurs in the soil and by chance infected one of his plants. The kaly seeds guy did graft all the time, many exposed cuts. Maybe one of his rootstocks got infested by gene transfering bacteria, and the infection spread from the rootstock into the scion, carrying with it the genome of one plant, into the next, thus creating a true chimera.
Anyway, it's just one way I can imagine how this may be possible outside of the laboratory.
The guy does have seeds of what he claims to be a chimera. I think I still got some somewhere. The seeds look normal obviously, since the mother was cannabis, but wouldn't it be interesting to see how the F2 would turn out?
Sadly, I've got bigger fish to fry. Your fish is the bigger fish namkha.
@ Azaghal
Were your Pinturas fully autoflowering? Mine were not but they were from the very first release.
When i first discovered this topic I've pondered the longest time over the idea if this might be something like naturally occuring protoplast fusion. In the lab they use bacteria from the genus Agrobacterium to transfer genes into plants. Maybe some species capable of gene transfer occurs in the soil and by chance infected one of his plants. The kaly seeds guy did graft all the time, many exposed cuts. Maybe one of his rootstocks got infested by gene transfering bacteria, and the infection spread from the rootstock into the scion, carrying with it the genome of one plant, into the next, thus creating a true chimera.
Anyway, it's just one way I can imagine how this may be possible outside of the laboratory.
The guy does have seeds of what he claims to be a chimera. I think I still got some somewhere. The seeds look normal obviously, since the mother was cannabis, but wouldn't it be interesting to see how the F2 would turn out?
Sadly, I've got bigger fish to fry. Your fish is the bigger fish namkha.@ Azaghal
Were your Pinturas fully autoflowering? Mine were not but they were from the very first release.
Ah I hate to double post, but I can't seem to find the edit button, help anyone?
Further Reading for the techy types :
http://en.wikipedia.org/wiki/Horizontal_gene_transfer
http://en.wikipedia.org/wiki/Somatic_fusion
Further Reading for the techy types :
http://en.wikipedia.org/wiki/Horizontal_gene_transfer
http://en.wikipedia.org/wiki/Somatic_fusion
tagging in for this.
I've been very interested in experimenting with grafting canna onto hops rootstock.
excited to follow your experiments!
I've been very interested in experimenting with grafting canna onto hops rootstock.
excited to follow your experiments!
Hi folks,
@ SapoVerde :
To be honest I experienced something similar like you did, the plant I kept went into flowering but never really finished ...
It had a broad range of old flowers together with new developing calyxes which eventually attracted Botrytis in the hot Summer months.
In the end I discarded this plant because it was the only one with Botrytis at that time and posed an infection risk for my other plants. Feedback from my friends was that they also lacked in potency and they are only ocassional smokers....
However it was worth a try and interesting enough Imho, regard Pintura Ruderalis more as an "ornamental" variety for people who like to grow exceptional cannabis with unique characteristics.
Cheers
@ SapoVerde :
To be honest I experienced something similar like you did, the plant I kept went into flowering but never really finished ...
It had a broad range of old flowers together with new developing calyxes which eventually attracted Botrytis in the hot Summer months.
In the end I discarded this plant because it was the only one with Botrytis at that time and posed an infection risk for my other plants. Feedback from my friends was that they also lacked in potency and they are only ocassional smokers....
However it was worth a try and interesting enough Imho, regard Pintura Ruderalis more as an "ornamental" variety for people who like to grow exceptional cannabis with unique characteristics.
Cheers
Information
Information
I guess they will make seeds but be infertile?
http://www.sciencedaily.com/releases/2010/03/100324142012.htm
A reliable method for producing plants that carry genetic material from only one of their parents has been discovered by plant biologists at UC Davis. The technique, to be published March 25 in the journal Nature, could dramatically speed up the breeding of crop plants for desirable traits.
The discovery came out of a chance observation in the lab that could easily have been written off as an error.
"We were doing completely 'blue skies' research, and we discovered something that is immediately useful," said Simon Chan, assistant professor of plant biology at UC Davis and co-author on the paper.
Like most organisms that reproduce through sex, plants have paired chromosomes, with each parent contributing one chromosome to each pair. Plants and animals with paired chromosomes are called diploid. Their eggs and sperm are haploid, containing only one chromosome from each pair.
Plant breeders want to produce plants that are homozygous -- that carry the same trait on both chromosomes. When such plants are bred, they will pass the trait, such as pest resistance, fruit flavor or drought tolerance, to all of their offspring. But to achieve this, plants usually have to be inbred for several generations to make a plant that will "breed true."
The idea of making a haploid plant with chromosomes from only one parent has been around for decades, Chan said. Haploid plants are immediately homozygous, because they contain only one version of every gene. This produces true-breeding lines instantly, cutting out generations of inbreeding.
Existing techniques to make haploid plants are complicated, require expensive tissue culture and finicky growing conditions for different varieties, and only work with some crop species or varieties. The new method discovered by Chan and postdoctoral scholar Ravi Maruthachalam should work in any plant and does not require tissue culture.
Ravi and Chan were studying a protein called CENH3 in the laboratory plant Arabidopsis thaliana. CENH3 belongs to a group of proteins called histones, which package DNA into chromosomes. Among the histones, CENH3 is found only in the centromere, the part of the chromosome that controls how it is passed to the next generation.
When cells divide, microscopic fibers spread from each end of the cell and attach at the centromeres, then pull the chromosomes apart into new cells. That makes CENH3 essential for life.
Ravi had prepared a modified version of CENH3 tagged with a fluorescent protein, and was trying to breed the genetically modified plants with regular Arabidopsis. According to theory, the cross should have produced offspring containing one mutant gene (from the mother) and one normal gene (from the father). Instead, he got only plants with the normal gene.
"At first we threw them away," Chan said. Then it happened again.
Ravi, who has a master's degree in plant breeding, looked at the plants again and realized that the offspring had only five chromosomes instead of 10, and all from the same parent.
The plants appear to have gone through a process called genome elimination, Chan said. When plants from two different but related species are bred, chromosomes from one of the parents are sometimes eliminated.
Genome elimination is already used to make haploid plants in a few species such as maize and barley. But the new method should be much more widely applicable, Ravi said, because unlike the process for maize and barley, its molecular basis is firmly understood.
"We should be able to create haploid-inducing lines in any crop plant," Ravi said. Once the haploid-inducing lines are created, the technique is easy to use and requires no tissue culture -- breeders could start with seeds. The method would also be useful for scientists trying to study genes in plants, by making it faster to breed genetically pure lines.
After eliminating half the chromosomes, Chan and Ravi had to stimulate the plants to double their remaining chromosomes so that they would have the correct diploid number. Plants with the haploid number of chromosomes are sterile.
The research also casts some interesting light on how species form in plants. CENH3 plays the same crucial role in cell division in all plants and animals. Usually, such important genes are highly conserved -- their DNA is very similar from yeast to whales. But instead, CENH3 is among the fastest-evolving sequences in the genome.
"It may be that centromere differences create barriers to breeding between species," Chan said. Ravi and Chan plan to test this idea by crossing closely-related species.
The work was supported by a grant from the Hellman Family Foundation.
Source: Originally Posted by ScienceDaily
A reliable method for producing plants that carry genetic material from only one of their parents has been discovered by plant biologists at UC Davis. The technique, to be published March 25 in the journal Nature, could dramatically speed up the breeding of crop plants for desirable traits.
The discovery came out of a chance observation in the lab that could easily have been written off as an error.
"We were doing completely 'blue skies' research, and we discovered something that is immediately useful," said Simon Chan, assistant professor of plant biology at UC Davis and co-author on the paper.
Like most organisms that reproduce through sex, plants have paired chromosomes, with each parent contributing one chromosome to each pair. Plants and animals with paired chromosomes are called diploid. Their eggs and sperm are haploid, containing only one chromosome from each pair.
Plant breeders want to produce plants that are homozygous -- that carry the same trait on both chromosomes. When such plants are bred, they will pass the trait, such as pest resistance, fruit flavor or drought tolerance, to all of their offspring. But to achieve this, plants usually have to be inbred for several generations to make a plant that will "breed true."
The idea of making a haploid plant with chromosomes from only one parent has been around for decades, Chan said. Haploid plants are immediately homozygous, because they contain only one version of every gene. This produces true-breeding lines instantly, cutting out generations of inbreeding.
Existing techniques to make haploid plants are complicated, require expensive tissue culture and finicky growing conditions for different varieties, and only work with some crop species or varieties. The new method discovered by Chan and postdoctoral scholar Ravi Maruthachalam should work in any plant and does not require tissue culture.
Ravi and Chan were studying a protein called CENH3 in the laboratory plant Arabidopsis thaliana. CENH3 belongs to a group of proteins called histones, which package DNA into chromosomes. Among the histones, CENH3 is found only in the centromere, the part of the chromosome that controls how it is passed to the next generation.
When cells divide, microscopic fibers spread from each end of the cell and attach at the centromeres, then pull the chromosomes apart into new cells. That makes CENH3 essential for life.
Ravi had prepared a modified version of CENH3 tagged with a fluorescent protein, and was trying to breed the genetically modified plants with regular Arabidopsis. According to theory, the cross should have produced offspring containing one mutant gene (from the mother) and one normal gene (from the father). Instead, he got only plants with the normal gene.
"At first we threw them away," Chan said. Then it happened again.
Ravi, who has a master's degree in plant breeding, looked at the plants again and realized that the offspring had only five chromosomes instead of 10, and all from the same parent.
The plants appear to have gone through a process called genome elimination, Chan said. When plants from two different but related species are bred, chromosomes from one of the parents are sometimes eliminated.
Genome elimination is already used to make haploid plants in a few species such as maize and barley. But the new method should be much more widely applicable, Ravi said, because unlike the process for maize and barley, its molecular basis is firmly understood.
"We should be able to create haploid-inducing lines in any crop plant," Ravi said. Once the haploid-inducing lines are created, the technique is easy to use and requires no tissue culture -- breeders could start with seeds. The method would also be useful for scientists trying to study genes in plants, by making it faster to breed genetically pure lines.
After eliminating half the chromosomes, Chan and Ravi had to stimulate the plants to double their remaining chromosomes so that they would have the correct diploid number. Plants with the haploid number of chromosomes are sterile.
The research also casts some interesting light on how species form in plants. CENH3 plays the same crucial role in cell division in all plants and animals. Usually, such important genes are highly conserved -- their DNA is very similar from yeast to whales. But instead, CENH3 is among the fastest-evolving sequences in the genome.
"It may be that centromere differences create barriers to breeding between species," Chan said. Ravi and Chan plan to test this idea by crossing closely-related species.
The work was supported by a grant from the Hellman Family Foundation.
Source:http://www.sciencedaily.com/releases/2010/03/100324142012.htm
Haploid Plants through Seeds
Tech ID: 19877 / UC Case 2010-030-0
Abstract
Researchers at the University of California Davis have developed a novel method to produce haploid plants through seeds. This method induces genome elimination (from one parent in a cross) with a precise mutation, rather than by culturing haploid cells or by crossing distantly related plants.
Full Description
Plant breeding relies on screening numerous plants to identify novel, desirable characteristics. Very large numbers of progeny from crosses often must be grown and evaluated over several years in order to select one or a few plants with a desired combination of traits.
Standard breeding of diploid plants often requires screening and back-crossing of a large number of plants to achieve the desired genotype. One solution to the problem of screening large numbers of progeny has been to produce haploid plants, the chromosomes of which can be doubled using colchicine or other means to achieve instantly homozygous, doubled-haploid plants.
With doubled haploid production systems, homozygosity is achieved in one generation. Thus, the breeder can eliminate the numerous cycles of inbreeding necessary to achieve practical levels of homzygosity using conventional methods. Indeed, true homozygosity for all traits is not achievable by conventional breeding methods.
Existing methods of generating haploid plants have numerous disadvantages. Culturing of haploid cells is expensive and laborious, and some species have proven recalcitrant to this technique. Crossing to a distantly related species (wide crosses) causes genome elimination in only a small number of species, and almost always requires embryo rescue in vitro to generate viable plants. Haploid-inducing lines in maize are genetically complex and yield haploids at low efficiency. All current methods may be extremely dependent on genotype. UC Davis researchers have developed a method of inducing haploids in a cross between plants of the same genotype which is based on exploitation of a universal feature of eukaryote chromosomes and which yields haploid plants from seeds.
Applications
This novel technology has multiple applications, including:
* Doubled haploid plants can rapidly create homozygous F2s from a hybrid F1.
* Haploid plants are very useful for genomics because they contain only one version of each gene.
* The method can transfer paternal chromosomes into maternal cytoplasm. Thus, it can create cytoplasmic male sterile lines with a desired genotype in a single step. Currently, generating a cytoplasmic male sterile line with a desirable genotype requires many generations of backcrossing.
Advantages
Using this innovative method:
* Genome elimination can be engineered with a precise molecular change that is not dependent on parental genotype. The gene that is manipulated is found in all eukaryotes and serves a universal function. Thus, haploid plants can be made in species where conventional methods, such as tissue culture of haploid cells and wide crosses, are typically unsuccessful.
* No tissue culture is required. Haploids are produced through seed by simple genetic crosses. This will greatly reduce the cost and labor required for haploid plant production, and make the process accessible to breeders lacking specialized expertise in culturing haploid cells.
* Plants from exactly the same cultivar can be crossed to eliminate one parental genome using a precise genetic change. This greatly simplifies synchronizing flowering time and readiness to cross (relative to the wide cross method of haploid production).
* This method yields haploid plants much more efficiently than current wide crossing protocols, or existing haploid inducers in maize.
* Apart from haploid-inducing lines in maize, this is the only known method of producing haploid plants in which paternal chromosomes are transferred into maternal cytoplasm, generating cytoplasmic male sterile lines with a desired genotype in a single step.
Related Materials
* Ravi M, Chan SW. 2010. Haploid plants produced by centromere-mediated genome elimination. Nature. 464(7288):615-8. - 03/25/2010
PATENT STATUS
* Patent Pending
INVENTORS
* Chan, Simon R.
* Maruthachalam, Ravi
Other Information
Categorized As
* Agriculture & Animal Science
o Plant Traits
o Transgenics
* Biotechnology
o Food
o Industrial/ Energy
* Research Tools
o Other
Related cases
2010-030-0
Keywords
haploid, plant, cultivar, breeding, transgenic
Contact
Randi L. Jenkins/ rljenkins@ucdavis.edu / tel: 530-754-7650 begin_of_the_skype_highlightin g 530-754-7650 end_of_the_skype_highlighting. Please reference Tech ID #19877.
Request Additional Information
UC Davis InnovationAccess
1850 Research Park Drive, Suite 100, Davis, CA 95618 | www.InnovationAccess.ucdavis.edu
Tel: 530.754.8649 begin_of_the_skype_highlightin g 530.754.8649 end_of_the_skype_highlighting | Fax: 530.754.7620 | innovationAccess@ucdavis.edu
© 2009 - 2010, The Regents of the University of California
Link: http://techtransfer.universityofcalifornia.edu/NCD/19877.html
Information
I guess they will make seeds but be infertile?
http://www.sciencedaily.com/releases/2010/03/100324142012.htm
A reliable method for producing plants that carry genetic material from only one of their parents has been discovered by plant biologists at UC Davis. The technique, to be published March 25 in the journal Nature, could dramatically speed up the breeding of crop plants for desirable traits.
The discovery came out of a chance observation in the lab that could easily have been written off as an error.
"We were doing completely 'blue skies' research, and we discovered something that is immediately useful," said Simon Chan, assistant professor of plant biology at UC Davis and co-author on the paper.
Like most organisms that reproduce through sex, plants have paired chromosomes, with each parent contributing one chromosome to each pair. Plants and animals with paired chromosomes are called diploid. Their eggs and sperm are haploid, containing only one chromosome from each pair.
Plant breeders want to produce plants that are homozygous -- that carry the same trait on both chromosomes. When such plants are bred, they will pass the trait, such as pest resistance, fruit flavor or drought tolerance, to all of their offspring. But to achieve this, plants usually have to be inbred for several generations to make a plant that will "breed true."
The idea of making a haploid plant with chromosomes from only one parent has been around for decades, Chan said. Haploid plants are immediately homozygous, because they contain only one version of every gene. This produces true-breeding lines instantly, cutting out generations of inbreeding.
Existing techniques to make haploid plants are complicated, require expensive tissue culture and finicky growing conditions for different varieties, and only work with some crop species or varieties. The new method discovered by Chan and postdoctoral scholar Ravi Maruthachalam should work in any plant and does not require tissue culture.
Ravi and Chan were studying a protein called CENH3 in the laboratory plant Arabidopsis thaliana. CENH3 belongs to a group of proteins called histones, which package DNA into chromosomes. Among the histones, CENH3 is found only in the centromere, the part of the chromosome that controls how it is passed to the next generation.
When cells divide, microscopic fibers spread from each end of the cell and attach at the centromeres, then pull the chromosomes apart into new cells. That makes CENH3 essential for life.
Ravi had prepared a modified version of CENH3 tagged with a fluorescent protein, and was trying to breed the genetically modified plants with regular Arabidopsis. According to theory, the cross should have produced offspring containing one mutant gene (from the mother) and one normal gene (from the father). Instead, he got only plants with the normal gene.
"At first we threw them away," Chan said. Then it happened again.
Ravi, who has a master's degree in plant breeding, looked at the plants again and realized that the offspring had only five chromosomes instead of 10, and all from the same parent.
The plants appear to have gone through a process called genome elimination, Chan said. When plants from two different but related species are bred, chromosomes from one of the parents are sometimes eliminated.
Genome elimination is already used to make haploid plants in a few species such as maize and barley. But the new method should be much more widely applicable, Ravi said, because unlike the process for maize and barley, its molecular basis is firmly understood.
"We should be able to create haploid-inducing lines in any crop plant," Ravi said. Once the haploid-inducing lines are created, the technique is easy to use and requires no tissue culture -- breeders could start with seeds. The method would also be useful for scientists trying to study genes in plants, by making it faster to breed genetically pure lines.
After eliminating half the chromosomes, Chan and Ravi had to stimulate the plants to double their remaining chromosomes so that they would have the correct diploid number. Plants with the haploid number of chromosomes are sterile.
The research also casts some interesting light on how species form in plants. CENH3 plays the same crucial role in cell division in all plants and animals. Usually, such important genes are highly conserved -- their DNA is very similar from yeast to whales. But instead, CENH3 is among the fastest-evolving sequences in the genome.
"It may be that centromere differences create barriers to breeding between species," Chan said. Ravi and Chan plan to test this idea by crossing closely-related species.
The work was supported by a grant from the Hellman Family Foundation.
Source: Originally Posted by ScienceDaily
A reliable method for producing plants that carry genetic material from only one of their parents has been discovered by plant biologists at UC Davis. The technique, to be published March 25 in the journal Nature, could dramatically speed up the breeding of crop plants for desirable traits.
The discovery came out of a chance observation in the lab that could easily have been written off as an error.
"We were doing completely 'blue skies' research, and we discovered something that is immediately useful," said Simon Chan, assistant professor of plant biology at UC Davis and co-author on the paper.
Like most organisms that reproduce through sex, plants have paired chromosomes, with each parent contributing one chromosome to each pair. Plants and animals with paired chromosomes are called diploid. Their eggs and sperm are haploid, containing only one chromosome from each pair.
Plant breeders want to produce plants that are homozygous -- that carry the same trait on both chromosomes. When such plants are bred, they will pass the trait, such as pest resistance, fruit flavor or drought tolerance, to all of their offspring. But to achieve this, plants usually have to be inbred for several generations to make a plant that will "breed true."
The idea of making a haploid plant with chromosomes from only one parent has been around for decades, Chan said. Haploid plants are immediately homozygous, because they contain only one version of every gene. This produces true-breeding lines instantly, cutting out generations of inbreeding.
Existing techniques to make haploid plants are complicated, require expensive tissue culture and finicky growing conditions for different varieties, and only work with some crop species or varieties. The new method discovered by Chan and postdoctoral scholar Ravi Maruthachalam should work in any plant and does not require tissue culture.
Ravi and Chan were studying a protein called CENH3 in the laboratory plant Arabidopsis thaliana. CENH3 belongs to a group of proteins called histones, which package DNA into chromosomes. Among the histones, CENH3 is found only in the centromere, the part of the chromosome that controls how it is passed to the next generation.
When cells divide, microscopic fibers spread from each end of the cell and attach at the centromeres, then pull the chromosomes apart into new cells. That makes CENH3 essential for life.
Ravi had prepared a modified version of CENH3 tagged with a fluorescent protein, and was trying to breed the genetically modified plants with regular Arabidopsis. According to theory, the cross should have produced offspring containing one mutant gene (from the mother) and one normal gene (from the father). Instead, he got only plants with the normal gene.
"At first we threw them away," Chan said. Then it happened again.
Ravi, who has a master's degree in plant breeding, looked at the plants again and realized that the offspring had only five chromosomes instead of 10, and all from the same parent.
The plants appear to have gone through a process called genome elimination, Chan said. When plants from two different but related species are bred, chromosomes from one of the parents are sometimes eliminated.
Genome elimination is already used to make haploid plants in a few species such as maize and barley. But the new method should be much more widely applicable, Ravi said, because unlike the process for maize and barley, its molecular basis is firmly understood.
"We should be able to create haploid-inducing lines in any crop plant," Ravi said. Once the haploid-inducing lines are created, the technique is easy to use and requires no tissue culture -- breeders could start with seeds. The method would also be useful for scientists trying to study genes in plants, by making it faster to breed genetically pure lines.
After eliminating half the chromosomes, Chan and Ravi had to stimulate the plants to double their remaining chromosomes so that they would have the correct diploid number. Plants with the haploid number of chromosomes are sterile.
The research also casts some interesting light on how species form in plants. CENH3 plays the same crucial role in cell division in all plants and animals. Usually, such important genes are highly conserved -- their DNA is very similar from yeast to whales. But instead, CENH3 is among the fastest-evolving sequences in the genome.
"It may be that centromere differences create barriers to breeding between species," Chan said. Ravi and Chan plan to test this idea by crossing closely-related species.
The work was supported by a grant from the Hellman Family Foundation.
Source:http://www.sciencedaily.com/releases/2010/03/100324142012.htm
Haploid Plants through Seeds
Tech ID: 19877 / UC Case 2010-030-0
Abstract
Researchers at the University of California Davis have developed a novel method to produce haploid plants through seeds. This method induces genome elimination (from one parent in a cross) with a precise mutation, rather than by culturing haploid cells or by crossing distantly related plants.
Full Description
Plant breeding relies on screening numerous plants to identify novel, desirable characteristics. Very large numbers of progeny from crosses often must be grown and evaluated over several years in order to select one or a few plants with a desired combination of traits.
Standard breeding of diploid plants often requires screening and back-crossing of a large number of plants to achieve the desired genotype. One solution to the problem of screening large numbers of progeny has been to produce haploid plants, the chromosomes of which can be doubled using colchicine or other means to achieve instantly homozygous, doubled-haploid plants.
With doubled haploid production systems, homozygosity is achieved in one generation. Thus, the breeder can eliminate the numerous cycles of inbreeding necessary to achieve practical levels of homzygosity using conventional methods. Indeed, true homozygosity for all traits is not achievable by conventional breeding methods.
Existing methods of generating haploid plants have numerous disadvantages. Culturing of haploid cells is expensive and laborious, and some species have proven recalcitrant to this technique. Crossing to a distantly related species (wide crosses) causes genome elimination in only a small number of species, and almost always requires embryo rescue in vitro to generate viable plants. Haploid-inducing lines in maize are genetically complex and yield haploids at low efficiency. All current methods may be extremely dependent on genotype. UC Davis researchers have developed a method of inducing haploids in a cross between plants of the same genotype which is based on exploitation of a universal feature of eukaryote chromosomes and which yields haploid plants from seeds.
Applications
This novel technology has multiple applications, including:
* Doubled haploid plants can rapidly create homozygous F2s from a hybrid F1.
* Haploid plants are very useful for genomics because they contain only one version of each gene.
* The method can transfer paternal chromosomes into maternal cytoplasm. Thus, it can create cytoplasmic male sterile lines with a desired genotype in a single step. Currently, generating a cytoplasmic male sterile line with a desirable genotype requires many generations of backcrossing.
Advantages
Using this innovative method:
* Genome elimination can be engineered with a precise molecular change that is not dependent on parental genotype. The gene that is manipulated is found in all eukaryotes and serves a universal function. Thus, haploid plants can be made in species where conventional methods, such as tissue culture of haploid cells and wide crosses, are typically unsuccessful.
* No tissue culture is required. Haploids are produced through seed by simple genetic crosses. This will greatly reduce the cost and labor required for haploid plant production, and make the process accessible to breeders lacking specialized expertise in culturing haploid cells.
* Plants from exactly the same cultivar can be crossed to eliminate one parental genome using a precise genetic change. This greatly simplifies synchronizing flowering time and readiness to cross (relative to the wide cross method of haploid production).
* This method yields haploid plants much more efficiently than current wide crossing protocols, or existing haploid inducers in maize.
* Apart from haploid-inducing lines in maize, this is the only known method of producing haploid plants in which paternal chromosomes are transferred into maternal cytoplasm, generating cytoplasmic male sterile lines with a desired genotype in a single step.
Related Materials
* Ravi M, Chan SW. 2010. Haploid plants produced by centromere-mediated genome elimination. Nature. 464(7288):615-8. - 03/25/2010
PATENT STATUS
* Patent Pending
INVENTORS
* Chan, Simon R.
* Maruthachalam, Ravi
Other Information
Categorized As
* Agriculture & Animal Science
o Plant Traits
o Transgenics
* Biotechnology
o Food
o Industrial/ Energy
* Research Tools
o Other
Related cases
2010-030-0
Keywords
haploid, plant, cultivar, breeding, transgenic
Contact
Randi L. Jenkins/ rljenkins@ucdavis.edu / tel: 530-754-7650 begin_of_the_skype_highlightin g 530-754-7650 end_of_the_skype_highlighting. Please reference Tech ID #19877.
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Link: http://techtransfer.universityofcalifornia.edu/NCD/19877.html
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This is also good to know a scientist developed a hormone treatment that interrupted the process that caused the hybrid seeds to abort. However can't find the hormones used?
http://www.sciencedaily.com/releases/2015/05/150512124140.htm
http://www.sciencedaily.com/releases/2015/05/150512124140.htm
