Integrating Herbicide-Resistant Corn Technology in a Kura Clover Living Mulch System

Abstract

and Moody, 1976). Also, when legumes are used as a living mulch, they can supply N to the main crop (Scott Previous research has shown that with adequate suppression, kura et al., 1987). clover (Trifolium ambiguum M. Bieb.) can be managed as a living mulch in corn (Zea mays L.); however, significant yield loss was Corn production in living mulch and interseeded sysobserved in some environments. This study evaluated two herbicide-tems typically results in yield loss in the North-Central resistant corn hybrids at three levels of kura clover living mulch USA from competition for moisture and N (Kurtz et suppression over multiple environments. In 1999 and 2000 near Arlingal., 1952; Pendleton et al., 1957). Fisher and Burrill ton and in 2000 near Lancaster, WI, glyphosate [N-(phosphonometh-(1993) and Zemenchik et al. (2000) also note that cool yl)glycine]-resistant corn (Roundup Ready corn, RRC) and glufosispring temperatures could reduce corn yields because nate [2-amino-4-(hydroxymethylphosphinyl) butanoic acid]-resistant of delayed planting or by giving a cool-season clover a corn (Liberty Link corn, LLC) hybrids were planted where kura clover competitive advantage over corn, a warm-season grass. had been (i) killed for monocrop corn, (ii) strongly suppressed with The key to the successful use of living mulches for glyphosate and dicamba (3,6-dichloro-2-methoxybenzoic acid), or (iii) corn production is controlling competition from the lightly suppressed with only glyphosate. Suppressed kura clover also had a 25-cm clopyralid (3,6-dichloro-2-pyridinecarboxylic acid) plus mulch crop. However, if the mulch suppression is excesdicamba-killed band into which corn was planted. Subsequent post-sive, it will not recover. Zemenchik et al. (2000) showed emergence applications of glyphosate or glufosinate herbicide were that corn could be grown in a kura clover living mulch made for each hybrid. Corn whole-plant yield ranged from 17.3 to when adequately suppressed by herbicide, without re-19.9 Mg ha Ϫ1 , and grain yield ranged from 10.8 to 12.3 Mg ha Ϫ1 .duced corn whole-plant or grain yields. In this system, Yield of whole-plant and grain across both corn hybrids did not differ kura clover will recover to full production within 12 mo between monocrop corn and corn in strongly suppressed kura clover. of corn harvest. However, corn performance in the living Whole-plant yield of monocrop corn was 8 to 11% greater and grain

Nitrogen Dynamics in Living Mulch and Annual Cover Crop Corn Production Systems

“…Reduced inorganic soil N in the LM cover crop system may be due to less total N applied, competition from intercropped clover for NO 3 -N, and reduced mineralization of clover residue. Other studies found similar grain yield reductions in living mulch systems and also concluded that early season competition between clover and corn was a mechanism for yield reductions (Scott et al, 1987;Echtenkamp and Moomaw, 1989;Zemenchik et al, 2000;Affeldt et al, 2004). A similar N uptake response in this study was noted in 2016, except differences in N uptake occurred earlier in the growing season and just after the V6 stage of corn development.…”

“…Periods of corn water stress were evident when demand from other research efforts resulted in limited opportunities for irrigation application. Regardless, mean N uptake and grain yields in this study (Table 2) were similar to N treatments in the kura clover system (Zemenchik et al, 2000;Affeldt et al, 2004).…”

“…Vegetable growers were the primary early adopters of LM systems (Paine and Harrison 1993), but recently interest has been emerging among grain crop producers (Rasse et al, 1999;Zemenchik et al, 2000;Duda et al, 2003;Nakamoto and Tsukamoto, 2006;Kramberger et al, 2009;Sanders et al, 2017). A concern with use of LM systems is the potential of a perennial cover crop competing with the cohabitating row crop (Kurtz et al, 1952;Zemenchik et al, 2000;Affeldt et al, 2004). In the southern Piedmont, corn requires 200 to 280 kg mineral N ha -1 to achieve maximum economic yield (Raun and Johnson, 1999;Lee et al, 2015).…”

Alfalfa Living Mulch Advances Biological Control of Soybean Aphid

“…In our case, increasing the abundance of natural enemies through the addition of a living mulch resulted in subeconomic A. glycines populations. Living mulches have been used in annual crop production with limited competition to the main crop (Affeldt et al 2004). We found evidence for signiÞcant competition between soybean and alfalfa, resulting in a yield reduction of Ϸ26% (N.P.S., unpublished data).…”

Assessing Carabid Contribution to Ecosystem Services: Does It Matter If There Are More Beetles?

“…When compared with conventional production methods, a legume living mulch can fix enough nitrogen to reduce fertilizer requirements and increase yields in the main crop (Ilnicki and Enache 1992). However, living mulches may need to be suppressed to reduce competition with the main crop when water and nutrients are scarce (Echtenkamp and Moomaw 1989, Tharp and Kells 2001, Affeldt et al 2004. Because living mulches reduce agricultural disturbances and increase vegetational diversity, changes in the community structure of arthropod pests and their natural enemies are likely (Andow 1991).…”