Table 1. Impact of primer efficiency on the Ct values and on the detected populations of total (live and “naturally dead”) or heat-killed bacteria.

The cells have been either non-treated (NT) or PMAxx–treated (PMA).

Primer pair	Sample	Ct value	ΔCt	CFU/mL	Primer efficiency	Amplicon size	Genomic position (bp) a
HL5/HL6	Total_NT	14.8±0.40		2.4*108±3.2*107	80.8%	221 bp	1,280,158–1,280,318
	Total_PMA	16.3±0.46		1.4*108±2.3*107
	Heat killed_NT	19.8±0.13	16.5±1.3	4.5*107±2.0*106
	Heat killed_PMA	36.3±1.35		2.0*105±8.3*104
PD0059	Total _NT	11.9±0.28		3.0*108 ±4.0*107	94.2%	178 bp	78,318–78,493
	Total_PMA	12.7±0.22		1.9*108±2.2*107
	Heat killed_NT	15.6±0.17	12.5±1	4.2*107±4.0*106
	Heat killed_PMA	28.1+/-1.1		1.1*105±5.8*104
PD1080	Total _NT	12.4±0.16		3.0*108±2.3*107	94.7%	122 bp	1,280,257–1,280,378
	Total_PMA	13.1±0.19		2.1*108±1.9*107
	Heat killed_NT	16.4±0.09	11.8±1.2	4.6*107±1.9*106
	Heat killed_PMA	28.2±1.28		2.0*105±1.2*105

^a Genomic positions are based on the genome of the X. fastidiosa Temecula1 strain.