Re: [pfaf] Re: another dimension - chenopodium rules!
On Thu, Apr 28, 2011 at 3:32 PM, travelerinthyme <traveler.in.thyme@...> wrote:
I still believe the problem is just that having such a thick stand the year before, Mother Nature rotated the crop and grew something else. I there was no other suitable place nearby for the seedlings to sprout, you may not have any this year.
Also, if all those plants came from one original mother plant, after so many generations they may just be too inbred.Hi Traveler,
inbreeding depression shouldn't affect the chenopodium genus. Its two most prominent species, C. quinoa and C. album are mostly self pollinated and only minimally wind pollinated. In addition to this, C. quinoa is always tetraploid and C. album is mostly hexaploid and tetraploid.
Tetraploid and hexaploid means they have 2 and 3 full replicas of the normal chromosome number (= 2n) for its species.
Simplifying, hexaploid plants tend to grow bigger and stronger than tretraploids and diploids because the expression of genetic defects is highly unlikely to happen due to the presence of additional DNA copies carrying normal genes which usually overcome defective ones. Thus no inbreeding depression should happen under normal circumstances.
The explanation then could be an exceptionally high density of roots from the previous year creating a crowded environment.. I've actually observed this on some occasions: quinoa sown near a mature quinoa plant in a pot germinated late and grew very stunted, while a seed from the same lot sown in fresh earth in a new pot grew normally.
I don't believe nutrients depletion is the only reason for this. The must be something in the root system telling individuals of the same species that "this place is mine".