Influence of Winter Annual Weed Management and Crop Rotation on Soybean Cyst Nematode (Heterodera glycines) and Winter Annual Weeds: Years Four and Five

Abstract

Certain winter annual weeds have been documented as alternative hosts to soybean cyst nematode (SCN), and infestations by such species are common in no-till production fields in the midwestern United States of Indiana, Ohio, and Illinois. The objective of this research was to determine the influence of crop rotation and winter annual weed management on winter weed growth, SCN population density, and crop yield. Two crop rotations (SS and soybean–corn rotation) and six winter annual weed-management systems (autumn-applied herbicide, spring-applied herbicide, autumn + spring applied herbicides, autumn-seeded Italian ryegrass, autumn-seeded wheat, and a nontreated check) were evaluated in long-term, no-tillage systems at West Lafayette, IN, and Vincennes, IN. In the fourth and fifth years of these experiments, the 2-yr corn–soybean rotation generally resulted in increased soybean yield, decreased winter annual weed growth, and reduced SCN population density compared with SS. Autumn or spring herbicide applications or both were a more effective option than cover crops at reducing winter annual weed density. Cover-crop systems generally did not differ from the nontreated check in winter weed density. Between years three and five, winter annual weed SCN hosts in nontreated check plots increased approximately threefold to levels as high as 102 and 245 plants m−2 at West Lafayette, IN, and Vincennes, IN, respectively, which are infestation levels at or above those commonly observed in production fields. However, controlling winter annual weeds did not influence crop yields or SCN population density. The results of these studies suggest that winter weed management, even at the high levels of weed infestation present in these studies, appears to have little value as a tool for SCN management in corn and soybean production systems in the midwestern United States.

Quantitative reproductive potential of Heterodera schachtii on weeds typical for late summer fallow in sugar beet rotations

“…Similar results for soyabean cyst nematode were found for the winter fallow period in soyabean production systems of the Midwest of the USA. Population densities of Heterodera glycines were minimally influenced even by multiyear differential weed management strategies (Mock et al ., ), despite the capacity of the nematode to reproduce on those weeds under commercial production conditions (Creech et al ., ).…”

Composition of the stubble weed flora and its role for Heterodera schachtii in the year preceding sugar beet production

“…The data of this survey suggested that the sole presence of the nematode hosts does not imply the need for weed management, as the impact of weeds at the densities observed on the population dynamic of H. schachtii may be limited. The results of the current survey were similar to those observed with the closely related H. glycines , where even a dense weed cover did not result in measurable population density build‐up (Mock et al ., ). The result of this survey corroborated results from a study under highly nematode‐conducive conditions, where high reproductive potential of many nematode hosts in the glasshouse was reflected by somewhat elevated nematode reproduction at high plant population densities only of Stellaria media and Thlaspi arvense in field microplots (Meinecke & Westphal, ).…”

“…But even high population densities of these principal weed hosts of H. glycines , including Lamium purpureum L., Lamium amplexicaule L., Stellaria media (L.) Vill., Capsella bursa‐pastoris (L.) Med. and Cardamine parviflora L., had limited measurable effects on nematode population densities (Mock et al ., ). If reproduction of H. glycines on L. amplexicaule was to become a problem, it could be suppressed by timely applications of 2,4‐D or glyphosate (Werle et al ., ).…”

Determination of weed hosts of soybean cyst nematode in South Dakota

“…Weed SCN hosts further complicate SCN management because of continued SCN development in the soil in the absence of soybean (Creech et al 2005; Johnson et al 2008; Nice and Johnson 2005; Poromarto et al 2015; Thomas et al 2005). Winter annual weeds emerge during fall, overwinter as seedlings, and then complete their life cycle in the spring (Mock et al 2007; Werle et al 2014). Previous studies have shown that there has been a surge in the winter annual weeds in different states that is probably due to factors such as increased conservation tillage practices, herbicide usage for weed management, and warmer winters in northern US regions (Johnson et al 2008; Krausz et al 2003; Thomas et al 2004).…”

“…), mouse-ear chickweed ( Cerastium fontanum Baumg. ), common mullein ( Verbascum thapsus L.), field pennycress or henbit ( Lamium amplexicaule L.), and purple deadnettle (Chen 2012; Giesler and Wilson 2011; Mock et al 2007; Poromarto et al 2015; Tylka 2012; Werle et al 2015). However, identification of SCN weed host species is complicated because of the genetic variability of HG types, localized environment, and selection pressure associated with different agronomic practices (Riggs and Schmitt 1988).…”