Table 2.

Hybridization in field (F) and greenhouse (GH) studies between a glyphosate-resistant Amaranthus palmeri pollen source and related Amaranthus species. Glyphosate treatment was used to identify hybrid plants expressing glyphosate resistance inherited from A. palmeri. Emerged plants were screened with glyphosate, and molecular markers were used to confirm hybrid plants

Maternal parent	Study	Total emerged progeny screened	Mean % emergence ± SE	χ2 test for expected emergence (20% F, 1% GH)	Mean % hybrids ± SE	Total hybrids	95% confidence interval (% hybrids)
1-A. palmeri	F	21 800	36 ± 6	3488; P < 0.0001	27.90 ± 2.80	–	(22.4, 33.4)
2-A. palmeri	F	3700	32 ± 6	333; P < 0.0001	21.10 ± 2.46	–	(16.3, 25.9)
3-Amaranthus hybridus	F	91 450	40 ± 3	22862; P < 0.0001	0.008 ± 0.006	2	(−0.004, 0.02)
	GH	462	5.2 ± 2	1561; P < 0.0001	0.0	0
4-A. hybridus	F	52 900	41 ± 4	14580; P < 0.0001	0.0	0
	GH	12	0.1 ± 0.2	72; P < 0.0001	0.0	0
5-Amaranthus powellii ssp. bouchonii	F	8700	20 ± 2	0; n.s.	0.0	0
6-A. powellii ssp. powellii	F	44 150	24 ± 2	441; P < 0.0001	0.0	0
	GH	33	0.4 ± 0.2	39; P < 0.0001	0.0	0
7-Amaranthus retroflexus	F	65 200	39 ± 4	14710, P < 0.0001	0.0	0
8-Amaranthus spinosus	F	60 400	96 ± 9	218 044; P < 0.0001	0.005 ± 0.004	2	(−0.003, 0.01)
9-A. spinosus	F	42 350	27 ± 2	1296; P < 0.0001	0.43 ± 0.07	211*	(0.29, 0.57)
	GH	533	7.9 ± 4	3266; P < 0.0001	1.44 ± 0.86	21*	(−0.25, 3.13)
10-Amaranthus tuberculatus	F	3350	3 ± 1	604; P < 0.0001	0.079 ± 0.059	2	(−0.04, 0.19)
	GH	1	0.02 ± 0.05	43; P < 0.0001	0.0	0
11-A. tuberculatus	F	3400	8 ± 2	306; P < 0.0001	0.19 ± 0.13	4	(−0.06, 0.44)
	GH	1	0.01 ± 0.03	69; P < 0.0001	0.0	0
12-A. tuberculatus	F	5550	17 ± 4	31; P < 0.0001	0.0	0

^*Subset of surviving plants tested to confirm hybrid identity.