Woolly Cupgrass Research Articles

Eriochloa villosa in the Primorsky Territory of Russia and the search for soil herbicides to combat it in soybean crops

The work analyzes the results of monitoring the weed field flora of the Primorsky Territory. A tendency has been revealed to increase the occurrence and density of the woolly cupgrass Eriochloa villosa (Thunb ex Murray.) Kunth, which is difficult to control due to a number of competitive biological advantages and morphological features that determine its resistance to many herbicides. In experiments conducted in 2021–2022. in the Far Eastern Scientific Research Institute of Plant Protection, it was revealed that according to the main indicator -a decrease in the wet above-ground mass of experimental weed plants compared to the control, the most effective herbicides were Dual Gold 1.6 l/ha, Proponit 3.0 l/ha and tank mixtures Dual Gold 1.5 l/ha + Gesagard 2.5 l/ha, Dual Gold 1.5 l/ha + Zenkor Ultra 0.5 l/ha, Dual Gold 1.5 l/ha + Command 0.7 l/ha.

First Report of Benzoxazinoid Compounds in Woolly Cupgrass (Eriochloa villosa Thunb. Kunth), an Invasive Plant

Woolly cupgrass (Eriochloa villosa Thunb. Knuth) is a common weed which is native to East Asia. It also was introduced into North America and Europe. The problems related to controlling this annual weed are due to its germination characteristics, low susceptibility to certain herbicides and considerable competitiveness against other plant species. Several genera of the Panicoideae subfamily contain benzoxazinoids, therefore we hypothesized that woolly cupgrass also produces these chemicals. To test this hypothesis, the benzoxazinoid content of plants at the flowering stage was investigated. Our results demonstrate the presence of benzoxaziniods in woolly cupgrass and this represents the first report of these compounds in this species within the Poaceae family and the Panicoideae subfamily. Benzoxazinoids likely account for the rapid spread and ecological success of woolly cupgrass in its invasive range.

The Impacts of Woolly Cupgrass on the Antioxidative System and Growth of a Maize Hybrid.

Woolly cupgrass (Eriochloa villosa (Thunb.) Kunth) is a new invasive weed in Hungary. This study was conducted to elucidate the effects of this weed on the biochemistry and growth of maize (Zea mays L. cv. Armagnac) under greenhouse conditions. Activities of the antioxidative enzymes (ascorbate peroxidase (APX), guaiacol peroxidase (POD), superoxide dismutase (SOD)), the contents of malondialdehyde (MDA), and protein were measured in the shoots and roots, whereas the content of the photosynthetic pigments was measured only in the shoots. The measured growth parameters included plant height, root length, root volume, root and shoot dry weight, and stem diameter. Results showed the allelopathic effects of woolly cupgrass on maize, with significant decreases in plant height, root length, root volume, and root dry weight. Woolly cupgrass infestation (WCI) induced significantly higher activities of APX and SOD in the shoots, whereas POD was only induced in the roots. The contents of chlorophyll-a, total chlorophyll (including relative chlorophyll), carotenoids, and root protein were substantially reduced by WCI, except for the leaf chlorophyll-b. The results suggest that high APX and SOD activities in the shoots could be involved in stabilizing the leaf chlorophyll-b, chlorophyll a/b, shoot protein, and shoot dry weight because all of these parameters were not inhibited when these two enzymes were induced. In contrast, high activity of POD in the roots is not effective in counteracting allelopathy. Therefore, it would be worthwhile to further investigate if an increase in the activities of APX and SOD in the shoots of WCI maize is responsible for stabilizing leaf chlorophyll-b, shoot protein, and shoot dry weight, which could contribute to improved maize yield under WCI.

Allelopathic effect of invasive plants (Eriochloa villosa, Asclepias syriaca, Fallopia x bohemica, Solidago gigantea) on seed germination

The aim of this study was to determine the allelopathic potential of invasive species woolly cupgrass (Eriochloa villosa), common milkweed (Asclepias syriaca), bohemian knotweed (Fallopia x bohemica), and giant goldenrod (Solidago gigantea Ait.) on germination crop (Lepidium sativum L.). Experiments were conducted under laboratory conditions to determine effect of water extracts in petri dish bioassay. Water extracts from fresh biomass (leaves and stem) of invasive weeds in concentrations of 4 and 8 g/100 ml were investigated. All invasive plants showed allelopathic effect on germination. In giant goldenrod stem water extract experiment, allelopathic effect was less pronounced.
 The cress germination was greatly suppressed with the woolly cupgrass, common milkweed and the giant goldenrod. The experiment showed that the seed germination depended on the concentrations and the plant material used (leaves and stem).

New occurence of woolly cupgrass (Eriochloa villosa [Thunb.] Kunth) in Hajdúság area, East-Hungary

Because of the globalization and global warming the emergence of invasive weeds in Hungary are more common. The woolly cupgrass (Eriochloa villosa [Thunb.] Kunth) is published as an important invasive weed in Hungary. Woolly cupgrass is native in East Asia and it spreads into several parts of the World and causes difficulties in plant protection. It has been spreading extensively during the last few years,as the weed shows a very serious invasion potential.

Allelopathic effects of water extracts of pieces of wooly cupgrass (Eriochloa villosa) on the seedlings of field crops

In Hungary, the woolly cupgrass (Eriochloa villosa [Thunb.] Kunth) endanger row crops (i.e. corn, sunflower). Its fast spreading based on some reason viz. long-lasting emergence, reduced sensitivity to many kinds of herbicides, vigorous competitional ability and fast initial growth. Allelopathy, ability of many plant species to produce one or more biochemicals wgich is used tocompete with each others. In this experiment we examined, whether the woolly cupgrass possesses allelopathy, and if so, how influences on the development of cultured crops like maize, sunflower and lettuce.

Impact of post-anthesis glyphosate on woolly cupgrass seed production, seed weight and seed viability

Nurse, R. E., Darbyshire, S. J. and Simard, M.-J. 2015. Impact of post-anthesis glyphosate on woolly cupgrass seed production, seed weight and seed viability. Can. J. Plant Sci. 95: 1193–1197. Herbicides are generally applied at early stages of crop and weed growth to protect crop yield. Few studies have evaluated the effect of late (post-anthesis) applications of glyphosate as a management option to limit the seed production of weed escapes, such as woolly cupgrass (Eriochloa villosa). We propagated woolly cupgrass under greenhouse conditions and then applied three glyphosate treatments post-anthesis including: (1) an untreated control; (2) 900 g a.e. ha−1; and (3) 1800 g a.e. ha−1. Terminal inflorescences were collected 21 d after glyphosate application, and seed production, seed weight and embryo viability were assessed. Post-anthesis glyphosate applications did not influence seed production, but reduced seed weight and viability by 50 and 96%, respectively. Therefore, glyphosate applied just before the woolly cupgrass inflorescence begins to emerge from the leaf sheath (as late as the R1 stage in soybeans) is an effective strategy to manage woolly cupgrass reproduction and stop viable seeds from entering the soil seed bank or other dispersal pathways.

Woolly cupgrass (Eriochloa villosa /Thunb./ Kunth), a recently occured invasive weed in Trans-Tisza Region and a trial for control in maize

To the effective control of invasive weeds are essential to prevent establish, if has already happened obstacle to massive accumulation, and promoting the efficient and rapid eradication, if it is possible. The Woolly cupgrass (Eriochloa villosa /Thunb./ Kunth) belongs to weeds which “hard to control” especially in corn. One of the difficulties of effective control is the prolonged emergence causing avoidance of several individuals the contact with pre-emergent herbicides. Another problem arises due to the intensive use of post-emergence herbicide products with short duration of action. To optimalize of timing of treatment is essential for successful control of later emerging weeds. The recently established Woolly cupgrass in Hungary shows resistance or reduced susceptibility to substantial portion of herbicides used in corn. The data collected from small-plot trials demonstrates that application of sulfonylurea or selective monoctyledonous herbicides can be effective against the Woolly cupgrass.

Emergence and seed production of woolly cupgrass (Eriochloa villosa) in legume forage crops

Simard, M.-J., Nurse, R. E. and Darbyshire, S. J. 2015. Emergence and seed production of woolly cupgrass (Eriochloa villosa) in legume forage crops. Can. J. Plant Sci. 95: 539–548. Woolly cupgrass is an annual grass of East Asian origin now present in North America, particularly in the US corn belt. The species was found in Canada in 2000 (southern Quebec). New, mostly small, populations have been discovered every year since 2007 and the species became a nationally regulated and quarantined weed in 2011. In order to evaluate the potential use of perennial legumes to reduce established populations, the emergence pattern, density, biomass and seed production of a woolly cupgrass population were evaluated in plots either kept unmanaged (control), in chemical fallow (treated with sequential applications of glyphosate) or cropped with alfalfa or clover from 2009 to 2011. Every year, woolly cupgrass seedlings started to emerge early (Apr. 29 to May 05) and continued to emerge over a 26- to 85-d period. All unma...

Comparative seed predation of woolly cupgrass (Eriochloa villosa) and yellow foxtail (Setaria pumila) along a field border in Canada

The seed predation of woolly cupgrass (Eriochloa villosa), an invasive weed of East‐Asian origin, was compared to that of yellow foxtail (Setaria pumila), an established and widespread weed, along a field border in Canada. The seeds of both species were glued to sandpaper cards and their removal in field conditions was recorded from July to September during the 3 years of 2009, 2010 and 2011. Predator exclusion cages allowed the evaluation of seed loss to be attributed to invertebrates, vertebrates and total seed loss due to predation for both species. Pitfall traps were installed and collected once in 2010 and during all the seed sampling dates in 2011 in order to evaluate predatory pressure from ground beetles and crickets. The average amount of seed loss that could be attributed to invertebrates was higher for S. pumila than for E. villosa, while the amount of seed loss that could be attributed to vertebrates was higher for E. villosa than for S. pumila in 2009 and 2010. The level of S. pumila seed loss to invertebrates was correlated with the sum of crickets (Gryllus pennsylvanicus) and beetles (Harpalus spp. and Ophonus rufibarbis) trapped during the 2011 season. During the same period, correlations between E. villosa seed loss to invertebrates and trapped insects were not observed. Reduced postdispersal seed predation by invertebrates could increase the local fall survival of the unburied seeds of invasive E. villosa populations, compared to other naturalized, smaller‐seeded weedy grasses.

Occurrence of woolly cupgrass (Eriochloa villosa /Thunb./ Kunth) in Hajdú-Bihar county, Hungary

Woolly cupgrass (Eriochloa villosa /Thunb./ Kunth) is native to East Asia, it spreads in several parts of the World and causes difficulties in plant protection, especially in maize. Difficulties in control of Eriochloa villosa originated from several reasons: seeds continue to germinate later in the season, significant part of seeds emerges from a deep layer of the soil, and the species is less susceptible to some herbicides applied to maize than other annual grass weeds.The first report on the occurrence of woolly cupgrass in Hungary was published in 2008, and it reported about the appearance of this species near to Gesztely village (Borsod-Abaúj-Zemplén county), however, no information has been added about spread of the weed in Hungary until now.A significant population was discovered next to Debrecen (Hajdú-Bihar county) in summer, 2011, and then weed associations were examined in maize, sunflower and stubble-fields on several km2 in the area to estimate the Eriochloa villosa infection. The weed species was found on every maize field bordering with a ground cover of 0.5-4%. Woolly cupgrass occurred inside of the 50% of maize fields, and reached a ground cover of 76% in case of most infected area, in addition it was found in sunflower and stubble-fields.The spread of woolly cupgrass is expected in this area, which requires the consideration of this species in the planning of weed management technologies.

Absorption and activity of foramsulfuron in giant foxtail (Setaria faberi) and woolly cupgrass (Eriochloa villosa) with various adjuvants

Greenhouse and laboratory studies were conducted to examine the activity and foliar absorption of foramsulfuron in giant foxtail and woolly cupgrass with various adjuvants. Adjuvant selection was important for giant foxtail control. Foramsulfuron provided 90% or greater giant foxtail control with the addition of methylated seed oil (MSO) or MSO plus 28% urea ammonium nitrate (UAN). When a crop oil concentrate (COC) or a nonionic surfactant (NIS) was added to foramsulfuron, giant foxtail control was only 20%. However, when 28% UAN was added to COC or NIS, control was increased to 90 and 85%, respectively. Foramsulfuron absorption and control were closely related in giant foxtail. Foliar absorption of14C-foramsulfuron in giant foxtail ranged between 35 and 90% 24 h after treatment (HAT) depending on adjuvant selection. The rate of absorption was greatest when MSO plus 28% UAN was added to foramsulfuron and absorption was maximized 4 HAT. Foramsulfuron absorption in woolly cupgrass reached its maximum levels 2 HAT with all adjuvant combinations. Although the rate of foramsulfuron absorption was quicker in woolly cupgrass, absorption trends by adjuvants were similar to those in giant foxtail. Maximum absorption of14C-foramsulfuron in woolly cupgrass was 84% with the addition of MSO plus 28% UAN. However, even with high levels of absorption, woolly cupgrass control with foramsulfuron was poor and may be related to rapid metabolism to nonphytotoxic compounds.

Evolved resistance to acetolactate synthase–inhibiting herbicides in common sunflower (Helianthus annuus), giant ragweed (Ambrosia trifida), and shattercane (Sorghum bicolor) in Iowa

Weed biotypes putatively resistant to acetolactate synthase (ALS)–inhibiting herbicides were reported by Iowa farmers from 1997 to 2001. Greenhouse studies confirmed cross-resistance to triazolopyrimidine sulfonanilide and sulfonylurea (SU) herbicides in giant ragweed from Scott County, IA (Werner Farm), which corresponded to resistance to susceptibility (R:S) GR50(50% growth reduction) ratios of 21 and 28 to cloransulam and primisulfuron + prosulfuron, respectively. At the enzyme level, this represented a 49- and 20-foldI50(50% enzyme inhibition) increase. Cross-resistance to imidazolinone (IMI) and SU herbicides was also observed in common sunflower from Cherokee, IA. Compared with a susceptible biotype, the resistant common sunflower biotype demonstrated GR50R:S ratios of 36 and 43 to imazethapyr and chlorimuron, respectively. Shattercane from Malvern, IA, was susceptible to nicosulfuron but was resistant to imazethapyr (GR50R:S ratio = 29). The woolly cupgrass biotypes from Union County, IA (Pettit Farm and Travis Farm), were reportedly resistant but were identified susceptible to both IMI and SU herbicides. Using an in vivo ALS assay, extractable endogenous 2,3-diketone concentrations ranged from 25 to 71 nmol g−1fresh weight for all species. Compared with susceptible biotypes, 2,3-diketone levels accumulated to at least twofold higher levels in treated resistant plants 120 h after herbicide application. Field history data suggested that resistance evolved independently in three environments where ALS-inhibiting herbicides represented an important component of the selection pressure.

Fate and persistence of woolly cupgrass (Eriochloa villosa) seed banks

Abstract Field experiments were conducted to quantify cumulative and annual rates of woolly cupgrass seedling emergence and seed mortality and to characterize woolly cupgrass seedling emergence patterns. Woolly cupgrass seed bank decline was rapid, declining by an average of 73, 96, and 99.5% after 1, 2, and 3 yr, respectively. Woolly cupgrass seed mortality accounted for a much greater portion of seed loss from the seed bank (80%) than germination and emergence (19.5%) during the 3-yr period. Annual rates of emergence ranged from 3 to 17% of the fall seed bank and were similar between seed banks established in different years when compared within the same year. Annual rates of mortality ranged from 50 to 92% and varied between seed banks established in different years when compared within the same year; older seed banks had higher rates of mortality than younger seed banks. For first-year seed banks, 97 to 99% of the total season emergence occurred within the first 3 wk of emergence. However, for second-...

Effect of seed reserve utilization on woolly cupgrass (Eriochloa villosa) development

Abstract Two experiments were conducted to examine woolly cupgrass seed reserve utilization and the effect of germination depth on seed reserve utilization, tiller number, and timing of tiller emergence. The first experiment included germination in light with water, in light with Hoagland's solution, and in darkness with water; the second included five planting depths of 1, 3, 5, 7, and 9 cm. Endosperm utilization and shoot and root growth over time were recorded. Endosperms lost weight rapidly until 6 d after germination (DAG), when weight loss slowed down. Endosperm weight loss ceased 8 or 10 DAG. Endosperm weight loss was fastest for germination in light with Hoagland's solution. Deep planting significantly decreased emergence rate and increased the time to emergence. Differences in residual endosperms may have affected the early development of woolly cupgrass seedlings. Germination from a depth of 9 cm depleted the endosperm by the time of emergence. Deep planting also decreased shoot dry weight and t...

Effect of Location and Burial Depth on Woolly Cupgrass (Eriochloa villosa) Seed Germination1

Woolly cupgrass seeds are dormant at physiological maturity and lose dormancy while afterripening in winter. Field experiments were conducted with the seeds collected from the locations across Iowa in the fall of 1991 and 1992. The seeds were buried in mid-November 0, 5, and 15 cm below the soil surface. Seeds were extracted biweekly until mid-February and germination tests conducted. Seeds buried below the soil surface were less dormant when compared with seeds on the soil surface. There were also dormancy differences between locations. Differences observed between locations and variations from 1991 to 1992 indicated that the parent plant environment, and the likely genotype, had a significant effect on woolly cupgrass seed dormancy.Nomenclature: Woolly cupgrass, Eriochloa villosa (Thunb.) Kunth #3 ERIVI.Additional index words: ABUTH, Abutilon theophrasti, acetochlor, afterripening, Amaranthus rudis, AMATA, atrazine, dormancy, pendimethalin, Setaria faberi, SETFA.Abbreviations: TZ, tetrazolium test.

Emergence and persistence of seed of velvetleaf, common waterhemp, woolly cupgrass, and giant foxtail

Abstract Annual emergence and seed persistence of common waterhemp, velvetleaf, woolly cupgrass, and giant foxtail were characterized in central Iowa for 4 yr following burial of seeds collected and buried in autumn 1994. First-year emergence as a percentage of the original seed bank ranged from 5 to 40%, and the relative order was common waterhemp < velvetleaf < giant foxtail < woolly cupgrass. During the second and third years, there were no differences in percent emergence among species, with emergence percentages ranging from 1 to 9% of the original seed bank. During the fourth year, seedlings continued to emerge from only the velvetleaf and common waterhemp seed banks. A greater percentage of common waterhemp seed persisted each year and 12% of the original seed was recovered after 4 yr of burial. Five percent of the velvetleaf was recovered at the end of the fourth year. No woolly cupgrass and giant foxtail seed was recovered after the third and fourth years. The proportion of the seed that was acco...

Woolly Cupgrass Management in Sethoxydim-Resistant Corn

Field studies were conducted from 1995 to 1997 to evaluate the potential for sethoxydim to control woolly cupgrass [Eriochloa villosa (Thunb.] Kunth.] in sethoxydim-resistant (SR) corn (Zea mays L.) and to identify potential interactions among sethoxydim and selected broadleaf herbicides. A single preemergence (PRE) application of acetochlor did not provide adequate season-long control of woolly cupgrass at 60 d after the postemergence (POST) timing. Sequential applications of acetochlor followed by sethoxydim or nicosulfuron improved woolly cupgrass control and plant density reduction. Sethoxydim controlled woolly cupgrass equal to or greater than acetochlor or nicosulfuron in all years. Split POST applications of sethoxydim provided 87% or greater woolly cupgrass control and 93% or greater plant density reduction. Dicamba, atrazine plus dicamba, bromoxynil, or halosulfuron did not reduce woolly cupgrass control by sethoxydim. However, atrazine plus bentazon and primisulfuron plus prosulfuron reduced woolly cupgrass control by sethoxydim resulting in greater plant densities compared with sethoxydim applied alone. These studies suggest that sethoxydim can be used as an effective tool in SR corn for control of woolly cupgrass.

Effects of stratification, temperature, and oxygen on woolly cupgrass (Eriochloa villosa) seed dormancy

Laboratory and field experiments were conducted to determine the effects of temperature, oxygen, and seed burial depth on woolly cupgrass seed dormancy. Woolly cupgrass seeds at physiological maturity are innately dormant. Stratifying these seeds at 5 C for 8 wk increased germination to greater than 90%, regardless of the germination temperature. Alternating the germination temperature hastened germination by 2 wk, while seedcoat removal hastened germination by another 4 wk. Low oxygen concentration was more detrimental to seed germination when seeds were subjected to constant temperatures in comparison to alternating temperatures. Oxygen concentration did not affect seed germination when seeds were placed in an alternating 15/25 C regime. Seed germination was approximately 15% less when seeds were stratified for 2 wk and subjected to oxygen concentrations below the ambient oxygen concentration, whereas this decrease was present only at the 8% oxygen concentration when seeds were stratified 4 wk. In the field, the stratification requirement was satisfied by early December for the study year. Seeds remaining on the soil surface overcame dormancy sooner than seeds buried 2 or 4 cm.

Sequential Applications Control Woolly Cupgrass (Eriochloa villosa) and Wild-Proso Millet (Panicum miliaceum) in Corn (Zea mays)

Field studies were conducted in 1994 and 1995 to determine the contribution of PRE applications of alachlor, metolachlor, acetochlor, SAN 582H, or pendimethalin on woolly cupgrass and wild-proso millet control when followed by POST nicosulfuron at 0, 0.018, 0.027, or 0.036 kg ai/ha. Sequential treatments controlled woolly cupgrass and wild-proso millet greater than single applications of PRE herbicides, which when applied alone resulted in the least wild-proso millet control and lowest corn grain yield. Lack of complete woolly cupgrass control with POST nicosulfuron alone resulted in corn grain yield that was less than with sequential treatments but was equal to PRE treatments. Wild-proso millet control with nicosulfuron at 0.027 kg/ha resulted in corn grain yield that was less than with sequential treatments, but greater than with all PRE treatments except for SAN 582H. All PRE herbicides, regardless of early season performance, when followed by nicosulfuron resulted in woolly cupgrass and wild-proso millet control that was similar. Woolly cupgrass seed production compared to the nontreated check was reduced 98% with acetochlor followed by nicosulfuron. Sequential treatments provided the most consistent woolly cupgrass and wild-proso millet control, the highest corn grain yield, and the greatest reduction in woolly cupgrass and wild-proso millet seed production.