Effect of Plant Population and Replant Method On Single-Row Peanut Production.

The University of Georgia Extension recommendation for optimum plant stand in peanut (Arachis hypogaea L.) is 13.1 plants m^‑1, although previous work has shown that yield potential can be maintained at plant stands lower than optimum.  The unpredictable and sometimes extreme weather, plus the ubiquity of pathogens in the region can contribute to poor emergence and a resultant poor plant stand.  When plant stand is adversely affected, a point is reached where replanting the field becomes economically viable.   The objectives of this study were to i) determine the plant stand at which a peanut field fails to maintain yield and economic viability in single row pattern, and ii) determine the best method for replanting peanut when an adequate stand is not achieved.  Field trials were established at the Southwest Georgia Research and Education Center in Plains, GA in 2011 and 2012 and at the Lang-Rigdon Farm in Tifton, GA in 2012.  Trials were designed to evaluate peanut production at six plant stands (3.3, 4.9, 6.6, 8.2, 9.8, and 11.5 plants m^-1) in combination with three replant regimes (no replant, destroy the original stand and replant at a full seeding rate, and add a reduced rate of seed to supplement the original stand), along with a 13.1 plants m^-1 check in a randomized complete block design.  To achieve maximum yield, a minimum plant stand of 3.3, 6.6, and 9.8 plants m^-1 were needed at Plains-2011, Tifton-2012, and Plains-2012, respectively.  Replanting by supplementing the original stand provided a yield increase at 3.3 plants m^-1 at Tifton-2012 and at 3.3 and 4.9 plants m^-1 at Plains-2012.  In all site-years, replanting by supplementing the original stand at a reduced seeding rate was more beneficial than destroying the original stand and completely replanting at a full seeding rate.