Skip to main content
ARS Home » Southeast Area » Auburn, Alabama » Soil Dynamics Research » Research » Publications at this Location » Publication #391468
Research Project: Conservation Systems to Improve Production Efficiency, Reduce Risk, and Promote Sustainability

Location: Soil Dynamics Research

Title: Influence of a cereal rye cover crop on the critical period for weed control in soybean

Author
item KUMARI, ANNU - Auburn University
item Price, Andrew
item KOORES, NICHOLAS - University Of Ioannina
item GAMBLE, AUDREY - Auburn University
item LI, STEVE - Auburn University

Submitted to: Weed Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/13/2022
Publication Date: N/A
Citation: N/A

Interpretive Summary: Herbicide resistant and troublesome weed control challenges limit soybean yield potential and threaten conservation systems. Cover crops have been increasingly adopted as an integrated pest management component, to suppress weeds and maintain soybean yield potential. A three-year field experiment was conducted to estimate the influence of a cereal rye cover crop and conservation tillage on critical period for weed control in soybean. The experiment included main plots as conventional tillage and conservation tillage following winter fallow and conservation tillage following rye cover crop as well as multiple durations of critical weed free period and timing. The results illustrated that weed biomass under conservation tillage + cover crop treatment was less than conventional tillage and conservation tillage + winter fallow systems during most of growing period. Averaged over the years, cover crop presence delayed the critical timing for weed removal by approximately 1.5 to 2 wk compared to conservation tillage + winter fallow treatments. Conservation tillage + winter fallow should be avoided to reduce weed competition and subsequent yield loss in soybean.

Technical Abstract: Soybean is the world’s most widely grown leguminous crop and is an important source of protein and oil for food and feed. However, resistant and troublesome weed control challenges limit yield potential and threaten conservation systems. Cover crops have been increasingly adopted as an integrated pest management component, to suppress weeds and maintain soybean yield potential. A three-year field experiment was conducted to estimate the influence of a cereal rye cover crop and conservation tillage on critical period for weed control (CPWC) in soybean. The experiment included main plots as conventional tillage (CVT) and conservation tillage following winter fallow (CT + WF) and conservation tillage following rye cover crop (CT + CC) as well as multiple durations of critical weed free period and timing. The results illustrated that weed biomass under CT + CC treatment was less than CVT and CT + WF systems during most of growing period. Moreover, the CPWC was the shortest in 2018 and 2019 following a cover crop while in the 2020 conventional tillage resulted in the shortest critical period. Averaged over the years, cover crop presence delayed the critical timing for weed removal (CTWR) by approximately 1.5 to 2 wk compared to CT + WF treatments. In addition, CVT delayed CTWR about 1.1 to 2 wk. compared with CT + WF. The 5% threshold limit relative yield loss was not attained up to 1wk after planting (WAP) for CT + WF and 3 WAP for CVT in all years, while CT + CC reported 3.2 WAP in both 2019 and 2020, but 2.5 WAP in 2018. In conclusion, CT + WF should be avoided to reduce weed competition and subsequent yield loss in soybean.