In:
Agronomy Journal, Wiley, Vol. 105, No. 4 ( 2013-07), p. 1077-1086
Abstract:
Management of winter annual weeds (WAWs) can affect soil N availability and corn ( Zea mays L.) production under no‐till systems. The objective of this study was to evaluate the effect of delaying WAW herbicide applications on N availability and grain yield for no‐till corn following soybean [ Glycine max (L.) Merr.]. Field research was conducted in 2010 and 2011 at 14 sites with naturally‐occurring populations of WAWs in eastern Kansas. A factorial arrangement of three herbicide application dates (November–March, April, and May) and five N rates (0, 17, 34, 67, and 135 kg N ha –1 ) were used to evaluate the interaction between weed and N response. Corn plant population, soil nitrate‐N, early corn N uptake, chlorophyll meter (CM) readings at silking, and grain yield were measured. Analysis across site‐years, no significant interaction occurred between herbicide application date and N rate for variables measured. Delaying herbicide application until April significantly reduced early corn N uptake by 52 mg N plant –1 , CM readings at silking by 3.4%, and grain yield by 0.48 Mg ha –1 across site‐years. Using the N fertilizer equivalence values (based on CM readings and grain yield), an estimated additional 16 to 17 kg N ha –1 was needed if herbicide application was delayed until April. Producers can increase corn N uptake and grain yield for rainfed no‐till corn following soybeans in eastern Kansas by applying herbicides on WAWs before April.
Type of Medium:
Online Resource
ISSN:
0002-1962
,
1435-0645
DOI:
10.2134/agronj2012.0344
Language:
English
Publisher:
Wiley
Publication Date:
2013
detail.hit.zdb_id:
1471598-3
