Response of Herbicide-Resistant Palmer Amaranth (Amaranthus palmeri) Accessions to Drought Stress

Table 4

Percent reduction in height and dry weight 30 days after emergence and the slopes of regression lines for percentage of reduction in height of 15 Palmer amaranth accessions^a.

Accession	County	Resistance^b	Height	Dry weight	Slope
			% reduction plant^−1		% reduction day^−1
1	Martin	ALSS/GS	11 b–d	27 b	5.5 a
2	Harnett	ALSS/GS	15 a	29 ab	4.5 abc
3	Lenoir	ALSS/GS	12 a–d	21 d	3.2 c
4	Martin	ALSS/GS	10 cd	16 e–g	3.5 c
5	Edgecombe	ALSS/GS	12 a–d	22 cd	3.3 c
6	Wayne	GR	13 a–c	14 fg	4.0 abc
7	Hoke	GR	14 ab	33 a	3.6 bc
8	Robeson	GR	9 d	20 de	3.4 c
9	Cumberland	GR	5 e	12 g	3.2 c
10	Scotland	GR	10 cd	18 d–f	3.3 c
11	Robeson	ALSR	13 a–c	22 cd	4.7 abc
12	Johnston	ALSR	13 a–c	16 e–g	5.1 ab
13	Robeson	ALSR	9 d	26 bc	3.6 bc
14	Sampson	ALSR	11 b–d	16 e–g	3.3 c
15	Edgecombe	ALSR	11 b–d	18 d–f	3.8 bc

^aData are pooled over experiments and duration of drought stress. Means within a parameter followed by the same letter are not significantly different according to Fisher’s Protected LSD test at 𝑃≤0.10.
^bAbbreviations: ALSS/GS: acetolactate synthase-inhibitor susceptible and glyphosate-susceptible accession; ALSR: acetolactate synthase inhibitor-resistant accession; GR: glyphosate-resistant accession.