See link below.
Link: jxb.oxfordjournals.org/content/early/2011/03/11/jxb.err052.abstract?papetoc
Hi Henry!
Their study is fascinating!! In addition to higher temperature, it is generally thought too that lower temperature can interfere or slow spindle fibers too and likely may be another reason for gametes having higher chromosome numbers. With a trend for higher ploidy levels (R. acicularis for instance as well as other genera) as one travels to colder regions, it would be interesting to characterize cooler temps and their impact In my potato work it is commonly understood, and I have found as well, varying rates of 2n gamete formation from the same genotypes across environments and temperature is thought to play a role.
This is great there is more information on this topic, especially in roses, so we can begin to use it if we want to go up in chromosome number. Meiotic polyploidization versus somatic sure seems to be the way to go whenever possible with outcrossing species like roses in order to keep heterozygosity high and hopefully relatively strong vigor.
C. C. Hurst commented (I don’t have the quotation handy) that Chinese shrubs grown in England sometimes got caught by an early frost, resulting in polyploid shoots.
Ive owned my Austin books for eons, but like everything, I read reference books in random order. So I was reading one of the books again yeaterday and I came across where it says that he believes that the more north you go, the more likely purple evolves. Likewise, the closer to the equator, the more white (or yellow, as it seems). It seems more like a generalized pattern, but I can see where he is led to perceive that pattern.
Oh yeah, he was talking about this, as well, in regarding to ploidy (and some random thoughts on stem weight, lol).