TABLE 3.

cRF of homologous crossovers occuring between BMV RNA1 and RNA2 molecules^a

Region between marker mutations	Host plantb	nc	n1	n2	nd	oRFd	nr	cRFe	cRF/100 nt
M2/M3 RNA2 (571 Int)	C. quinoa—local lesion	39	13	16	10	26%	20.21	51%	8.9%
	C. quinoa—whole leaf	36	21	11	4	22%	8.9	49%	8.6%
	barley	59	18	31	10	17%	21.5	36%	6.3%
M3/M4 RNA2 (811 nt)	C. quinoa—local lesion	39	19	15	5	13%	10.1	26%	3.2%
	C. quinoa—whole leaf	36	21	11	4	22%	8.9	49%	6.0%
	barleyf	62	27	21	14	22%	28.4	45%	5.5%
M4/M6 RNA2 (809 nt)	C. quinoa—local lesion	17	7	7	3	18%	6.0	35%	4.4%
	C. quinoa—whole leaf	53	28	21	4	15%	8.2	31%	3.8%
	barley	71	39	22	10	14%	21.7	31%	3.8%
O3/O6 RNA1 (962 nt)	barley	63	40	16	7	11%	17.1	27%	2.8%
O6/O8 RNA1 (1465 nt)	barley	55	26	14	15	27%	31.25	57%	3.9%

^aRecombination frequency was counted as the ratio of recombinants and the total number of analyzed clones.

^bBecause only 50% local lesions on C. quinoa leaves were doubly infected with both parental RNA1 or RNA2 variants, the recombination frequencies for the whole-leaf infections were approximated by dividing into half the number of the examined clones.

^cAll variants of n were calculated using equations 1 to 4 (see Results).

^doRF = n_d/n.

^ecRF = n_r/n.

^fRecombination frequency within M3/M4 region of RNA2 BMV in barley is the sum of results obtained after coinoculation experiments with M2-/M34-RNA2-BMV and M34-/M6-RNA2-BMV mutants (Fig. 2).