Table 4.

Correlation and regression analysis of rDNA copy number with strain features

Species	Factor 1	No. of strains	Factor 2	No. of levels	r	P
Saccharomyces paradoxus	rDNA copy number	26	Geographical origin	3	− 0.287	0.293
Saccharomyces cerevisiae	rDNA copy number	34	Strain group	8	− 0.253	0.240
	rDNA copy number	34	Genome type	2	− 0.057	0.676
	rDNA copy number	34	Modified genome type	3	− 0.037	0.896
	rDNA copy number	32	Strain group	8	− 0.627	3.89 × 10−5a
	rDNA copy number	32	Genome type	2	0.299	0.049
	rDNA copy number	32	Modified genome type	3	− 0.129	0.006

Notes: Pearson's correlation coefficients (r) were calculated between rDNA copy number and strain features for various numbers of strains. Negative Binomial Generalised Linear Models were also fitted to the same datasets, with P-values for the resulting χ² analysis of deviance test also found.

^aFurthermore, the Negative Binomial regression indicated that the rDNA copy numbers of the Sake, Wine/European, North American and UWOPS Mosaics groups were significantly different from possessed by the Other Mosaics group, with P = 0.002, P = 1.09 × 10⁻⁵, P = 0.003, and P = 0.001 respectively.