Premium
Starter Nitrogen and Growth Habit Effects on Late‐Planted Soybean
Author(s) -
Starling Michael E.,
Wood C. Wesley,
Weaver David B.
Publication year - 1998
Publication title -
agronomy journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 131
eISSN - 1435-0645
pISSN - 0002-1962
DOI - 10.2134/agronj1998.00021962009000050015x
Subject(s) - starter , indeterminate growth , habit , sowing , dry matter , cultivar , agronomy , yield (engineering) , biology , crop , horticulture , psychology , materials science , food science , metallurgy , ideotype , psychotherapist
In the Gulf Coast region of the southeastern USA, soybean [ Glycine max (L.) Merr.] is often planted in a double‐cropped system following corn ( Zea mays L.). In this system, soybean planting date is delayed from the optimal range (mid‐May to mid‐June) to late July, causing a substantial yield reduction. Potential grain yield response has led to increased interest in indeterminate growth habit and N application for late‐planted, double‐cropped soybean systems. Our objective was to determine the interactiv effects of growth habit (determinate and indeterminate stem termination types) and starter N (0 and 50 kg ha −1 ) on soybean growth and yield when planted following corn in a double‐crop system. Three Maturity Group VIII soybean genotypes [the near‐isolines Au86‐2397I ( Dt 1 Dt 1 , indeterminate) and Au86‐2397D (dt 1 dt 1 , determinate) and a determinate check cultivar, Cook] were planted in late July in seven Alabama environments during 1995 and 1996. Starter N increased R1 dry matter for both Au86‐2397D and Au86‐2397I by 0.50 Mg ha −1 . Au86‐2397I had 1 cm greater average plant height at the R1 developmental stage and 14 cm greater height at R8 than Au86‐2397D. Au86‐2397I yielded 0.16 Mg ha −1 more than its determinate near‐isoline. Application of starter N decreased the number of nodules per root, but increased plant N concentration and dry matter yield. Grain yield was increased on average by 0.15 Mg ha −1 with addition of starter N. In this study, an indeterminate genotype soybean coupled with application of starter N promoted greater soybean growth and yield in a late‐planted, double‐cropped system.