A mutual titer-enhancing relationship and similar localization patterns between Citrus exocortis viroid and Hop stunt viroid co-infecting two citrus cultivars

Table 2 The significance of correlation coefficients between Citrus exocortis viroid (CEVd) and Hop stunt viroid (HSVd) from two infected citrus cultivars under different temperature conditions

	Correlation coefficients between CEVd and HSVd
	Blood orange^a			Murcott mandarin^a
Temperature	Low	Moderate	High	Low	Moderate	High
All^b	++^c	++	-	++	++	++
Rootstock bark	-^d	++	-	++	+	++
Root	-	-	-	-	++	++
Twig bark	-	-	-	-	-	-
Leaf	-	-	-	-	++	-

^aThree nonparametric methods are Spearman’s nonparametric correlation coefficient, Kendall tau rank correlation coefficient and Hoeffding’s inequality
^bAll = overall data of blood oranges or Murcott mandarins
^ccorrelation coefficients marked with “++” are statistically significant by all three methods and those marked with “+” are statistically significant by two of three methods
^dindicates data are not significantly difference

ISSN: 1743-422X