Will novel soybean herbicide tolerance traits solve my pigweed problem?
2021
- Department of Agronomy, UW Madison
Project Media
Recently developed herbicide trait platforms have provided soybean growers with
additional tools for POST-emergent pigweed management including 2,4-D choline (Enlist E3TM
soybean), dicamba (Xtend, Xtendflex), and glufosinate (Liberty Link, LLGT27, and Xtendflex).
Pigweed (waterhemp and Palmer amaranth) management in soybeans can prove rather difficult
as previously there were limited POST herbicide options available. Recent research from the
UW-Madison Cropping Systems Weed Science program has shown that resistance to glyphosate
(Group 9), imazethapyr (Group 2), and PPO-inhibitor (Group 14) is widespread in waterhemp
populations across Wisconsin. With limited POST options and widespread herbicide-resistance,
we anticipate a heavy reliance on 2,4-D choline, dicamba, and glufosinate in the coming growing
seasons. Alone, these POST herbicides will not be enough to provide season long waterhemp
control in soybeans and growers will need to adopt more effective integrated weed management
strategies. It is imperative that herbicide stewardship is used when relying on these herbicides so
that their effectiveness is preserved, and the onset of herbicide resistance is delayed. Moreover,
previous research from our lab indicates that season long waterhemp control is more likely when
effective PRE-emergence residual herbicides are adopted.