A case study of GM maize gene flow in South Africa

Environmental Sciences Europe

Table 1 Theoretical isolation distances derived from 1.0%, 0.1%, 0.01% and 0.001% cross-pollination

Percentage cross-pollination	Mean BV06^a(m)	Mean BV07^b(m)	Mean WB07^c(m)	Comb Mean^d(m)	High BV06^e(m)	High BV07^f(m)	High WB07^g(m)	Comb high^h(m)	Meanⁱ(90% CI)^j(m)	Meanⁱ(95% CI)^k(m)	Meanⁱ(99% CI)^l(m)
1.0	9	14	16	14	28	34	40	36	20	19	17
0.1	33	42	50	45	122	129	141	135	125	119	110
0.01	114	126	159	145	530	491	494	503	792	759	694
0.001	398	377	501	473	2298	1861	1739	1869	5041	4861	4386

^aBainsvlei 2005/2006 (R² = 0.90; y = -1.8422x + 1.7856); ^bBainsvlei 2006/2007 (R² = 0.92; y = -2.0359x + 2.3363); ^cWaterbron 2006/2007 (R² = 0.91; y = -2.1033x + 2.5423); ^dcombined mean cross-pollination across all trial sites (R² = 0.95; y = -1.9509x + 2.2181); ^eBainsvlei 2005/2006 (R² = 0.80; y = -1.5652x + 2.2691); ^fBainsvlei 2006/2007 (R² = 0.92; y = -1.7271x + 2.6474); ^gWaterbron 2006/2007 (R² = 0.91; y = -1.8318x + 2.9335);^hcombined high cross-pollination across all trial sites (R² = 0.97; y = -1.7547x + 2.7405); ⁱthe datasets were combined and the means calculated with a 90%, 95% and 99% CI, respectively; ^jisolation distances derived from means from the combined dataset with a 90% CI (R² = 0.92; y = -1.2445x + 1.6078); ^kisolation distances derived from means from the combined data with a 95% CI (R² = 0.95; y = -1.2401x + 1.5719); ^lisolation distances derived from means from the combined data with a 99% CI (R² = 0.96; y = -1.2493x + 1.55). Theoretical isolation distances (metres) are derived from 1.0%, 0.1%, 0.01% and 0.001% cross-pollination using logarithmic equations for mean cross-pollination and combined means over distance compared to high cross-pollination over distance for Bainsvlei 2005/2006 (BV06), Bainsvlei 2006/2007 (BV07) and Waterbron 2006/2007 (BV07) (P << 0.01). The theoretical isolation distances were also calculated after combining the data sets from means with a 90%, 95% and 99% confidence interval (CI), respectively.