International Scholarly Research Notices

Research Article

Influence of Soybean (Glycine max) Population and Herbicide Program on Palmer Amaranth (Amaranthus palmeri) Control, Soybean Yield, and Economic Return

Table 7

The influence of herbicide resistance trait, soybean population, and preemergence and postemergence herbicides on Palmer amaranth control 2 weeks after post application in Field E3 during 2011.^a


Soybean population^b			Palmer amaranth control
	Herbicide application timing		Herbicide resistance trait^d
	Preemergence^c	Postemergence	Glufosinate		Glyphosate
				%

Low	None	No	0d		0d
Low	S-metolachlor	No	83bc		85bc
Low	S-metolachlor plus fomesafen	No	95ab		100a
Low	None	Yes	76c		78c
Low	S-metolachlor	Yes	98a		100a
Low	S-metolachlor plus fomesafen	Yes	100a		100a
High	None	No	0d		0d
High	S-metolachlor	No	98a		98a
High	S-metolachlor plus fomesafen	No	95ab		100a
High	None	Yes	85bc		85bc
High	S-metolachlor	Yes	100a		100a
High	S-metolachlor plus fomesafen	Yes	100a		100a

^aMeans within a HRT followed by the same letter are not significantly different according to Fisher’s Protected LSD test at P < 0.05.
^bLow soybean population in Field E3 in 2011 was 193,000 plants m⁻². High soybean population in this field was 533,000 plants m⁻².
^cS-metolachlor and S-metolachlor plus fomesafen applied at 1500 and 1200 + 270 g ha⁻¹, respectively.
^dGlufosinate and glyphosate applied to appropriate herbicide-resistant cultivar at 560 and 840 g ha⁻¹, respectively.