By the way - and answering on the initial posting of this theme:
Here is one 1960s original paper on Polyploidy in garden tulips. Access is free!
Abstract
The effect of nitrous oxide on chromosome doubling of young wheat plants from anther culture was investigated and compared with the effect of colchicine treatment. Two colchicine treatments (0.01% and 0.005% for 24 h) were compared with two treatments with nitrous oxide (24 h and 48 h at 6 atm. pressure). Both N2O treatments were as efficient as 0.01% colchicine in inducing seed setting in the treated plants. The colchicine treatment, however, killed a significant proportion of the treated plants, while the N2O treatments appeared non-toxic. The chromosome doubling effect of nitrous oxide combined with its low toxicity makes it an interesting possible alternative to colchicine for investigations of chromosome doubling of haploid plants, especially during the early stages of anther culture.
Its again easy to choose.
Grx!
Arno
Link: www.sciencedirect.com/science/article/pii/0168945288901161