Sulfur Cinquefoil (Potentilla recta) Response to Defoliation on Foothill Rangeland

2012 ◽  
Vol 5 (4) ◽  
pp. 408-416 ◽  
Author(s):  
Rachel A. Frost ◽  
Jeffrey C. Mosley
Keyword(s):  
Seed Production ◽  
Aboveground Biomass ◽  
The United States ◽  
Livestock Grazing ◽  
Optimal Timing ◽  
Western Canada ◽  
Viable Seed ◽  
Southwestern Montana ◽  
Aboveground Productivity ◽  
Control Response

AbstractSulfur cinquefoil is an invasive, perennial forb on rangelands of western Canada and the United States. Sulfur cinquefoil reproduces solely by seed and it is a prolific seed producer. Our 2-yr study (2006, 2007) investigated the optimal timing and intensity of defoliation to decrease aboveground productivity and seed production of sulfur cinquefoil plants on foothill rangeland in southwestern Montana. Each year, 150 sulfur cinquefoil plants within a 430-m2 enclosure were tagged for identification and randomly assigned to one of 15 clipping treatments with 10 plants per treatment. Clipping treatments were conducted at three timings: (preflower [early June], flowering [late June], and seedset [mid-July]) and all possible combinations of timings for a total of seven timing treatments clipped to two stubble heights (7.5 cm or 15 cm), comprising 14 unique treatments. The final (15th) treatment consisted of an unclipped control. Response variables collected at senescence (late July) included aboveground biomass; number of buds, flowers and fruits on each plant; and number and viability of seeds produced. Results indicated that defoliation of sulfur cinquefoil can effectively reduce its yield and seed production. All clipping treatments reduced aboveground biomass of sulfur cinquefoil compared with control plants (P ≤ 0.05), except clipping to 15 cm during preflowering in the wetter year of 2006. Clipping to either 7.5 cm or 15 cm at all times or combinations of timings reduced the number of buds, flowers, fruits, and seeds produced by sulfur cinquefoil (P ≤ 0.05). Viable seed production was reduced 99 to 100% when plants were clipped once to either 7.5 or 15 cm during flowering or seedset. Results suggest that targeted livestock grazing or mowing applied one time per season during flowering or seedset could effectively suppress the biomass production and viable seed production of sulfur cinquefoil.

Postharvest Kochia (Kochia scoparia) Management with Herbicides in Small Grains

2004 ◽  
Vol 18 (2) ◽  
pp. 426-431 ◽  
Author(s):  
James A. Mickelson ◽  
Alvin J. Bussan ◽  
Edward S. Davis ◽  
Andrew G. Hulting ◽  
William E. Dyer
Keyword(s):  
Leaf Area ◽  
Seed Production ◽  
Field Experiments ◽  
Optimal Timing ◽  
Viable Seed ◽  
Kochia Scoparia ◽  
Application Timing ◽  
Herbicide Treatments ◽  
Small Grains ◽  
Viable Seeds

Uncontrolled kochia plants that regrow after small-grain harvest can produce substantial numbers of seeds. An average of 4,100 seeds per plant were produced between harvest (late July to mid August) and the first killing frost (late September) at three locations in Montana. Field experiments were conducted to determine the optimal timing of postharvest herbicide applications to prevent kochia from producing viable seeds. Herbicide treatments were applied at three timings from late August to mid September. The most effective treatments were glyphosate (631 g/ha) and paraquat (701 g/ha) applied at the second application timing (late August to early September). These treatments reduced kochia seed production by 92% or greater at each site. Kochia regrowth by this time had sufficient leaf area for herbicide absorption, but few viable seed had been produced. Herbicide treatments at the first and third application timings were generally less effective and more variable in reducing kochia seed production. Sulfentrazone (157 g/ha) and 2,4-D (561 g/ha) were not as effective at reducing seed production as other herbicide treatments.

scholarly journals Effect of Herbicide Management Practices Used by Invasive Plant Managers onBerteroa incana(Hoary Alyssum) Seed Biology and Control

2018 ◽  
Vol 11 (2) ◽  
pp. 101-106
Author(s):  
Uriel D. Menalled ◽  
Stacy C. Davis ◽  
Jane M. Mangold
Keyword(s):  
Population Density ◽  
Seed Production ◽  
Management Practices ◽  
Invasive Plant ◽  
Seed Viability ◽  
Viable Seed ◽  
Southwestern Montana ◽  
Seed Biology ◽  
Spraying Plants ◽  
Herbicide Management

AbstractHoary alyssum [Berteroa incana(L.) DC.] is a nonnative invasive forb that is noxious in California, Idaho, Michigan, Montana, Oregon, Washington, Wyoming, Alberta, British Columbia, and Saskatchewan. ManagingB. incanais difficult, because it has an extended flowering period, during which plants simultaneously flower and produce seeds. Consequently, poorly timed herbicide applications may killB. incanaflowers but not prevent viable seed production. We examined how different herbicide management practices used by invasive plant managers affectedB. incanaseed production and viability the year of application as well as population density 1 yr after application. Professional invasive plant managers sprayedB. incanawith various herbicides as part of their current management practices at six sites in southwestern Montana in summer 2016. We collectedB. incanaplants at 4 wk postapplication for seed biology analyses. Across the six sites, nonsprayedB. incanaproduced 5 to 1,855 seeds plant−1and averaged 429 seeds plant−1. Seed production was reduced by 64% to 99% with 7 of the 11 herbicide applications.Berteroa incanaseed viability in nonsprayed areas averaged 53% and ranged from 36% to 73% across the sites. Nine of the 10 herbicide applications used by invasive plant managers reduced seed viability 49% to 100%. Few of the herbicide management practices reducedB. incana’s population density the following growing season, suggesting that managers should expect reoccurring infestations at least 1 yr after application. Our results show that invasive plant managers can reduceB. incanaviable seed production even when spraying plants that have flowered and formed seed pods. However, sites may need to be monitored for additional years to treat reoccurring infestations.

scholarly journals Do applications of systemic herbicides when green fruit are present prevent seed production or viability of Alliaria petiolata (garlic mustard)?

2021 ◽  
pp. 1-17
Author(s):  
Leo Roth ◽  
José Luiz C. S. Dias ◽  
Christopher Evans ◽  
Kevin Rohling ◽  
Mark Renz
Keyword(s):  
Seed Production ◽  
Seed Viability ◽  
Early Spring ◽  
Alliaria Petiolata ◽  
Late Spring ◽  
Garlic Mustard ◽  
Viable Seed ◽  
Application Timing ◽  
Control Seed ◽  
Second Year

Garlic mustard [Alliaria petiolata (M. Bieb.) Cavara & Grande] is a biennial invasive plant commonly found in the northeastern and midwestern United States. Although it is not recommended to apply herbicides after flowering, land managers frequently desire to conduct management during this timing. We applied glyphosate and triclopyr (3% v/v and 1% v/v using 31.8% and 39.8% acid equivalent formulations, respectively) postemergence to established, second-year A. petiolata populations at three locations when petals were dehiscing, and evaluated control, seed production and seed viability. Postemergence glyphosate applications at this timing provided 100% control of A. petiolata by 4 weeks after treatment at all locations whereas triclopyr efficacy was variable, providing 38-62% control. Seed production was only reduced at one location, with similar results regardless of treatment. Percent seed viability was also reduced, and when combined with reductions in seed production, we found a 71-99% reduction in number of viable seed produced plant-1 regardless of treatment. While applications did not eliminate viable seed production, our findings indicate that glyphosate and triclopyr applied while petals were dehiscing is a viable alternative to cutting or hand-pulling at this timing as it substantially decreased viable A. petiolata seed production. Management Implications Postemergence glyphosate and triclopyr applications in the early spring to rosettes are standard treatments used to manage A. petiolata. However, weather and other priorities limit the window for management, forcing field practitioners to utilize more labor-intensive methods such as hand-pulling. It is not known how late in the development of A. petiolata these herbicides can be applied to prevent viable seed production. Since prevention of soil seedbank replenishment is a key management factor for effective long-term control of biennial invasive species, we hypothesized late spring foliar herbicide applications to second year A. petiolata plants when flower petals were dehiscing could be an effective management tool if seed production or viability is eliminated. Our study indicated that glyphosate applications at this timing provided 100% control of A. petiolata plants by 4 weeks after treatment at all locations, whereas triclopyr efficacy was inconsistent. Although both glyphosate and triclopyr decreased viable seed production to nearly zero at one of our three study locations, the same treatments produced significant amounts of viable seed at the other two locations. Our findings suggest late spring glyphosate and triclopyr applications should not be recommended over early spring applications to rosettes for A. petiolata management, as our late spring application timing did not prevent viable seed production, and may require multiple years of implementation to eradicate populations. Nonetheless, this application timing holds value in areas devoid of desirable understory vegetation compared to no management practices or mechanical management options including hand-pulling when fruit are present, as overall viable seed production was reduced to similar levels as these treatments.

scholarly journals Cryogenic Storage of Tomato Pollen: Effect on Fecundity

HortScience ◽  
1996 ◽  
Vol 31 (3) ◽  
pp. 447-448 ◽  
Author(s):  
Erik J. Sacks ◽  
Dina A. St. Clair
Keyword(s):  
Lycopersicon Esculentum ◽  
Seed Production ◽  
Fruit Set ◽  
Viable Seed ◽  
Pollen Storage ◽  
Germplasm Storage ◽  
Cryogenic Storage ◽  
Fresh Pollen ◽  
Tomato Breeding ◽  
Pollen Effect

The influence of cryogenic pollen storage on fruit set and seed production in tomato (Lycopersicon esculentum Mill.) was investigated. Flowers pollinated with pollen samples stored for 5 weeks at –80C, with or without 20 h precooling at 4C, had similar fruit set and number of viable seed per fruit as those pollinated with fresh pollen. Pollen samples, which were repeatedly cooled (–80C) and warmed (to 22 to 24C) for up to six cycles, continuously maintained the same viability as the fresh pollen. When cryogenically stored pollen of L. esculentum 2-837, LA359, LA3198, and LA3199 were used to pollinate LA359, the number of viable seed formed per fruit differed significantly. Results of this study suggest that pollen cryopreservation can be used successfully for tomato breeding and germplasm storage.

scholarly journals First Report of Phytophthora infestans Genotype US23 Causing Late Blight in Canada

Plant Disease ◽  
2011 ◽  
Vol 95 (7) ◽  
pp. 873-873 ◽  
Author(s):  
L. M. Kawchuk ◽  
R. J. Howard ◽  
R. D. Peters ◽  
K. I. Al-Mughrabi
Keyword(s):  
United States ◽  
Late Blight ◽  
Phytophthora Infestans ◽  
The United States ◽  
Western Canada ◽  
Eastern Canada ◽  
Disease Symptoms ◽  
Metalaxyl Sensitivity ◽  
Epidemiological Characteristics

Late blight is caused by the oomycete Phytophthora infestans (Mont.) de Bary and is one of the most devastating diseases of potato and tomato. Late blight occurs in all major potato- and tomato-growing regions of Canada. Its incidence in North America increased during 2009 and 2010 (2). Foliar disease symptoms appeared earlier than usual (June rather than July) and coincided with the identification of several new P. infestans genotypes in the United States, each with unique characteristics. Prior to 2007, isolates collected from potato and tomato crops were mainly US8 or US11 genotypes (1). However, P. infestans populations in the United States have recently experienced a major genetic evolution, producing isolates with unique genotypes and epidemiological characteristics in Florida and throughout the northeastern states (2). Recent discoveries of tomato transplants with late blight for sale at Canadian retail outlets prompted an examination of the genotypes inadvertently being distributed and causing disease in commercial production areas in Canada. Analysis of isolates of P. infestans from across Canada in 2010 identified the US23 genotype for the first time from each of the four western provinces (Manitoba, Saskatchewan, Alberta, and British Columbia) but not from eastern Canada. Allozyme banding patterns at the glucose phosphate isomerase (Gpi) locus indicated a 100/100 profile consistent with US6 and US23 genotypes (4). Mating type assays confirmed the isolates to be A1 and in vivo metalaxyl sensitivity was observed. Restriction fragment length polymorphic analysis of 50 isolates from western Canada with the multilocus RG57 sequence and EcoRI produced the DNA pattern 1, 2, 5, 6, 10, 13, 14, 17, 20, 21, 24, 24a, 25 that was indicative of US23 (3). The recently described P. infestans genotype US23 appears to be more aggressive on tomato, and although isolates were recovered from both tomato and potato, disease symptoms were often more severe on tomato. Results indicate that movement and evolution of new P. infestans genotypes have contributed to the increased incidence of late blight and that movement of the pathogen on retail plantlets nationally and internationally may provide an additional early season source of inoculum. A major concern is that the introduced new A1 populations in western Canada have established a dichotomy with the endogenous A2 populations in eastern Canada, increasing the potential for sexual recombination producing oospores and additional genotypes should these populations merge. References: (1) Q. Chen et al. Am. J. Potato Res. 80:9, 2003. (2) K. Deahl. (Abstr.) Phytopathology 100(suppl.):S161, 2010. (3) S. B. Goodwin et al. Curr. Genet. 22:107, 1992. (4) S. B. Goodwin et al. Phytopathology 88:939, 2004.

scholarly journals Flowering, Fecundity, Seed Germination, and Seed Viability of Viburnum opulus L. Cultivars

2009 ◽  
Vol 27 (1) ◽  
pp. 31-36
Author(s):  
Janine R. Conklin ◽  
James C. Sellmer
Keyword(s):  
Seed Germination ◽  
Seed Production ◽  
Seed Viability ◽  
Biological Traits ◽  
Limited Information ◽  
Viable Seed ◽  
Invasive Potential ◽  
Short Term ◽  
Viburnum Opulus ◽  
Tetrazolium Test

Abstract Mature specimens of Viburnum opulus and cultivars ‘Leonard's Dwarf’ and ‘Roseum’ were assessed over 2 years for flower and seed production, seed germination, and seed viability as determined by a tetrazolium test to understand their invasive potential. ‘Aureum’, ‘Compactum’, ‘Losely's Compact’, ‘Nanum’, and ‘Xanthocarpum’ were also tested for germination and viability of seeds. Cultivars differed in flower and seed production, seed germination, and seed viability. ‘Roseum’ prolifically produced highly viable seed that germinated at moderate rates under greenhouse conditions (8,354, 100%, and 73%, respectively). Viburnum opulus and ‘Leonard's Dwarf’ produced fewer viable seed which showed moderate to low germination rates (609, 100%, and 53%; 712, 100%, and 5%, respectively). ‘Aureum’ and ‘Xanthocarpum’ seeds germinated at moderate rates (55 and 25%, respectively) and were highly viable (100%). ‘Compactum’, ‘Losely's Compact’, and ‘Nanum’ germinated at low rates or failed to germinate (0, 0, and 5%, respectively), yet seeds were moderately viable (37, 65, and 55%, respectively). Seeds of all cultivars germinated at low rates or failed to germinate at both outdoor sites (0 to 5%) which suggests these plants may be weakly invasive. Short-term studies on biological traits such as these provide only limited information to assess the invasive potential of cultivars.

Abstract 119: Initiating Oral Anticoagulation 4 to 14 Days After a Cardioembolic Stroke is Not Associated With a Reduction in Ischemic or Hemorrhagic Events: The IAC Multicenter Cohort

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Shadi Yaghi ◽  
Tushar Trivedi ◽  
James Giles ◽  
Angela Liu ◽  
Muhammad Nagy ◽  
...  
Keyword(s):  
United States ◽  
Oral Anticoagulation ◽  
Infarct Volume ◽  
Recurrent Stroke ◽  
Composite Endpoint ◽  
The United States ◽  
Cardioembolic Stroke ◽  
Optimal Timing ◽  
Symptomatic Intracerebral Hemorrhage ◽  
Ischemic Events

Background/Aims: Guidelines suggest initiating anticoagulation after cardioembolic stroke within 4-14 days from the index event. Data supporting this suggestion did not account for important factors such as infarct burden or early hemorrhagic transformation. Methods: We pooled data from stroke registries of 8 comprehensive stroke centers across the United States. We included consecutive patients admitted with an acute cardioembolic stroke in the setting of atrial fibrillation. The primary predictor was timing of initiating anticoagulation (0-3 days, 4-14 days, or >14 days) and the primary outcome was the composite endpoint of recurrent stroke/TIA/systemic embolism, symptomatic intracerebral hemorrhage (sICH), or major extracranial hemorrhage (ECH) within 90 days. Results: We enrolled 2090 patients from 8 comprehensive centers in the United States, 1325 met the inclusion criteria (362 were excluded due to non-composite endpoint related death within 90 days, 145 lost to follow up, and 258 were not started on oral anticoagulation or the timing was not reported). Anticoagulation (875 DOAC, 404 Warfarin) was initiated in 0-3 days in 49.7%, 4-14 days in 40.4%, and >14 days in 9.9%. The combined endpoint occurred in 10.7% (142) (98 ischemic events, 21 sICH, and 30 ECH) and did not differ between the three groups: 0-3 days (11.9%), 4-14 days (9.9%), >14 days (9.9%), p=0.525. After adjusting for confounders (such as infarct volume, bridging, CHADS2-Vasc, cardiac thrombus, and hemorrhage on 24-hr imaging), oral anticoagulation timing in the 4-14 day period (vs. >14) was not associated with a reduction in ischemic events (adjusted OR 0.74, p=0.438) and oral anticoagulation timing 4-14 days (vs. 0-3) was not associated with a reduction in sICH (OR 1.28, p=0.638). Factors associated with sICH were bridging (OR 5.36, p=0.001) and hemorrhage on 24-hr imaging (OR 7.26, p<0.001) whereas for ischemic events were warfarin treatment (OR 1.66 95%, p = 0.030) and prior stroke (OR 1.81, p=0.013). Conclusion: In this multicenter real world cohort, the recommended (4-14 days) timeframe to start oral anticoagulation was not associated with reduced ischemic and hemorrhagic outcomes. Randomized trials are required determine the optimal timing of anticoagulation initiation.

scholarly journals Allometric Equation Development, Biomass, and Aboveground Productivity in Ponderosa Pine Forests, Black Hills, Wyoming

2010 ◽  
Vol 25 (3) ◽  
pp. 112-119 ◽  
Author(s):  
Daniel Tinker ◽  
Gail K. Stakes ◽  
Richard M. Arcano
Keyword(s):  
Carbon Storage ◽  
Ponderosa Pine ◽  
Aboveground Biomass ◽  
Carbon Allocation ◽  
Black Hills ◽  
Allometric Equations ◽  
Pine Forests ◽  
Mature Trees ◽  
Ponderosa Pine Forests ◽  
Aboveground Productivity

Abstract Temperate forest ecosystems continue to play an important role in the global carbon cycle, and the ability to accurately quantify carbon storage and allocation remains a critical tool for managers and researchers. This study was aimed at developing new allometric equations for predicting above- and belowground biomass of both mature trees and saplings of ponderosa pine trees in the Black Hills region of the western United States and at evaluating thinning effects on biomass pools and aboveground productivity. Study sites included three stands that had been commercially thinned and one unmanaged stand. Nine allometric equations were developed for mature trees, and six equations were developed for saplings; all models exhibited strong predictive power. The unmanaged stand contained more than twice as much total aboveground biomass as any of the thinned stands. Aboveground biomass allocation among tree compartments was similar among the three older stands but quite different from the young, even-aged stand. Stand-level aboveground net primary production was higher in the unmanaged and intensively managed stands, yet tree-level annual productivity was much lower in the unmanaged stands than in any of the managed forests, suggesting that thinning of some forest stands may increase their ability to sequester and store carbon. Our data also suggest that different management approaches did not have the same effect on carbon allocation as they did on total carbon storage capacity, but rather, stand age was the most important factor in predicting carbon allocation within individual trees and stands. Identification of the relationships between stand structure and forest management practices may help identify various management strategies that maximize rates of carbon storage in ponderosa pine forests.

Influence of Planting Date on the Growth of Johnsongrass (Sorghum halepense) from Seed

Weed Science ◽  
1979 ◽  
Vol 27 (5) ◽  
pp. 554-558 ◽  
Author(s):  
P. E. Keeley ◽  
R. J. Thullen
Keyword(s):  
Seed Production ◽  
Planting Date ◽  
Sorghum Halepense ◽  
Viable Seed ◽  
Fresh Weight ◽  
Total Fresh Weight

Seed of johnsongrass [Sorghum halepense(L.) Pers.] were planted during 1976 and 1977 at monthly intervals from March through October to study the growth and reproductive habits of this weed at Shafter, California. Plants were grown for 12 weeks and harvested at 3-week intervals. Emergence and development of plants increased with temperature. April through August plantings yielded 10-to 20-fold as much total fresh weight as March and September plantings. After planting, rhizome production normally began in 3 to 6 weeks and seed production in 6 to 9 weeks. From the April through August plantings, rhizomes accounted for averages of 13, 25, and 40% of the total fresh weight of plants 6, 9, and 12 weeks after planting, respectively. This compared, respectively, with 16, 9, and 6% for roots and 70, 66, and 54% for shoots. Seedlings emerging in March produced rhizomes in early June and viable seed in late June. Seedlings emerging as late as September produced rhizomes and some viable seed before killing frosts in November.

scholarly journals Comanaging fresh produce for nature conservation and food safety

2015 ◽  
Vol 112 (35) ◽  
pp. 11126-11131 ◽  
Author(s):  
Daniel S. Karp ◽  
Sasha Gennet ◽  
Christopher Kilonzo ◽  
Melissa Partyka ◽  
Nicolas Chaumont ◽  
...  
Keyword(s):  
Food Safety ◽  
Fresh Produce ◽  
Foodborne Pathogen ◽  
The United States ◽  
Livestock Grazing ◽  
Central Coast ◽  
E Coli ◽  
Vegetation Removal ◽  
Pathogen Prevalence ◽  
Coast Region

In 2006, a deadly Escherichia coli O157:H7 outbreak in bagged spinach was traced to California’s Central Coast region, where >70% of the salad vegetables sold in the United States are produced. Although no definitive cause for the outbreak could be determined, wildlife was implicated as a disease vector. Growers were subsequently pressured to minimize the intrusion of wildlife onto their farm fields by removing surrounding noncrop vegetation. How vegetation removal actually affects foodborne pathogens remains unknown, however. We combined a fine-scale land use map with three datasets comprising ∼250,000 enterohemorrhagic E. coli (EHEC), generic E. coli, and Salmonella tests in produce, irrigation water, and rodents to quantify whether seminatural vegetation surrounding farmland is associated with foodborne pathogen prevalence in California’s Central Coast region. We found that EHEC in fresh produce increased by more than an order of magnitude from 2007 to 2013, despite extensive vegetation clearing at farm field margins. Furthermore, although EHEC prevalence in produce was highest on farms near areas suitable for livestock grazing, we found no evidence of increased EHEC, generic E. coli, or Salmonella near nongrazed, seminatural areas. Rather, pathogen prevalence increased the most on farms where noncrop vegetation was removed, calling into question reforms that promote vegetation removal to improve food safety. These results suggest a path forward for comanaging fresh produce farms for food safety and environmental quality, as federal food safety reforms spread across ∼4.5 M acres of US farmland.

Sign in / Sign up

Export Citation Format

Share Document