TABLE 2.

Systemic infectivity of BYV-GFP and its mutant variants

Classa	BYV variant	No. of infected plants/no. of inoculated plants	Systemic infectivityb	Time of symptom appearance (wk)
I	BYV-GFP	16/18	89	3
	A3	13/18	72	6
	A4	11/18	61	3
	A6	14/18	78	3
	A8	13/18	72	3
	A10	14/18	78	3
	A11	16/18	89	3
	A14	12/18	67	3
	A16	14/18	78	3
	A18	11/18	61	3
	A23	11/18	61	3
	A27	15/18	83	3
II	A2	1/18	6	3
	A9	8/18	44	3
	A12	9/18	50	3
	A15	4/18	22	5
	A21	9/18	50	4
	A25	7/18	39	4
III	A5	0/18	0	NAc
	A7	0/18	0	NA
	A17	0/18	0	NA

^aThe BYV-GFP variants are arbitrarily divided into classes according to efficiency of systemic infection. These efficiencies are ≥61% for class I, ≤50% for class II, and zero for class III.

^bExpressed as percentages of the infected versus inoculated plants.

^cNA, not applicable.