Stability of corn (Zea mays)-foxtail (Setariaspp.) interference relationships

Abstract

Variation in interference relationships have been shown for a number of crop-weed associations and may have an important effect on the implementation of decision support systems for weed management. Multiyear field experiments were conducted at eight locations to determine the stability of corn-foxtail interference relationships across years and locations. Two coefficients (IandA) of a rectangular hyperbola equation were estimated for each data set using nonlinear regression procedures. TheIandAcoefficients represent percent corn yield loss as foxtail density approaches zero and maximum percent corn yield loss, respectively. The coefficientIwas stable across years at two locations and varied across years at four locations. Maximum yield loss (A) varied between years at one location. Both coefficients varied among locations. Although 3 to 4 foxtail plants m−-1row was a conservative estimate of the single-year economic threshold (Tc) of foxtail density, variation inIandAresulted in a large variation inTc. Therefore, the utility of using common coefficient estimates to predict future crop yield loss from foxtail interference between years or among locations within a region is limited.

Interactions Among Western Corn Rootworm (Coleoptera: Chrysomelidae), Yellow Foxtail, and Corn

“…Thus foxtail may provide a buffer to rootworm damage to corn, with the caveat that unlimited foxtail growth will lead to crop yield losses because of foxtail interference (Lindquist et al 1999). Adults emerged later from foxtail band areas and had smaller head capsule size than did individuals from areas without foxtail.…”

Influence of Yellow Foxtail on Corn Growth and Yield

“…At harvest, the N treatment increased grain yield in the weed-free treatment from about 9,200 to 11,800 kg ha 21 but did not influence stover biomass. Nitrogen also alleviated yield loss when yellow foxtail did not exceed 400 plants m 22 (Lindquist et al 1999 …”

“…Yellow foxtail has been reported to reduce corn yield up to 80%, although the amount of crop yield reduction varies widely among sites, years, and yellow foxtail densities (Lindquist et al, 1999). Cultural management of corn, such as row spacing (Forcella, Westgate, and Warnes 1992;Anderson 2000) and N application (Nieto and Staniforth 1961;Tollenaar et al 1992), influences yield loss due to weeds.…”

“…The maximum yield loss based on density (A d ) in 1995 was about 65% (Lindquist et al 1999), whereas A b was 57% (Table 3). The 10% grain yield loss due to yellow foxtail biomass was estimated to occur at about 110 g m 22 .…”

“…emerged at the V1 -V2 stage of corn growth compared with losses when it emerged at or after V4 stage of corn growth. Lindquist et al (1999) reported on the stability of corn -foxtail (giant, green, and yellow) interference relationships across the midwestern United States, including Brookings and Morris. Whereas A d (the maximum percent corn yield loss) was stable for Brookings and Morris within a site, I d varied between sites and years.…”