Evaluation of Factors That Influence Benghal Dayflower (Commelina benghalensis) Seed Germination and Emergence

Weed Science ◽  
2012 ◽  
Vol 60 (1) ◽  
pp. 75-80 ◽  
Author(s):  
Mercy H. Sabila ◽  
Timothy L. Grey ◽  
Theodore M. Webster ◽  
William K. Vencill ◽  
Donn G. Shilling
Keyword(s):  
Seed Germination ◽  
Soil Profile ◽  
The United States ◽  
Response To Treatment ◽  
Effect Of Temperature ◽  
Physical Dormancy ◽  
Planting Depth ◽  
Commelina Benghalensis ◽  
Primary Means ◽  
Benghal Dayflower

A perennial species in its native range of Asia and Africa, Benghal dayflower in North America establishes annually from seed. This species has the unique ability to produce aerial and subterranean flowers and seeds. Information on how various environmental factors affect Benghal dayflower aerial and subterranean seed germination and emergence in the United States is lacking. Studies were conducted to determine the effect of temperature, planting depth, salt concentration, and pre-emergence herbicides on germination or emergence of aerial and subterranean Benghal dayflower seed. Maximum aerial seed germination occurred at 30 C, whereas maximum subterranean seed germination occurred at 30 and 35 C. Germination at 40 C was delayed relative to optimum temperatures. The seed coats in this study were mechanically disrupted to evaluate the response of seeds to temperature in the absence of physical dormancy. The physical dormancy imposed by the seed coat could require additional study. Benghal dayflower was not tolerant to ≥ 10 mM NaCl, indicating that this exotic species is not likely to become problematic in brackish marshes and wetlands of coastal plain regions. There was an inverse linear response of Benghal dayflower emergence and planting depth, with no emergence occurring at a planting depth of 12 cm. A field survey of Benghal dayflower emergence revealed that 42% of plants established from a depth of 1 cm in the soil profile, with 7 cm being the maximum depth from which seedlings plants could emerge. This suggests that PRE herbicides must remain in the relatively shallow depths of the soil profile to maximize control of germinating seedlings. Subterranean seeds were less sensitive than aerial seeds toS-metolachlor, the primary means of controlling this species in cotton. There were no differences between the germination of aerial and subterranean seed in response to treatment with diclosulam.

Benghal Dayflower (Commelina benghalensis) Seed Viability in Soil

Weed Science ◽  
2012 ◽  
Vol 60 (4) ◽  
pp. 589-592 ◽  
Author(s):  
Mandeep K. Riar ◽  
Theodore M. Webster ◽  
Barry J. Brecke ◽  
David L. Jordan ◽  
Michael G. Burton ◽  
...  
Keyword(s):  
United States ◽  
North Carolina ◽  
Regression Model ◽  
Seed Viability ◽  
The United States ◽  
The Other ◽  
Weed Species ◽  
Physical Dormancy ◽  
Commelina Benghalensis ◽  
Benghal Dayflower

Benghal dayflower is an exotic weed species in the United States that is a challenge to manage in agricultural fields. Research was conducted in North Carolina, Georgia, and Florida to evaluate the longevity of buried Benghal dayflower seeds. Seeds were buried in the field for 2 to 60 mo at a depth of 20 cm in mesh bags containing soil native to each area. In North Carolina, decline of Benghal dayflower seed viability was described by a sigmoidal regression model, with seed size having no effect on viability. Seed viability at the initiation of the study was 81%. After burial, viability declined to 51% after 24 mo, 27% after 36 mo, and < 1% after 42 mo. In Georgia, initial seed viability averaged 86% and declined to 63 and 33% at 12 and 24 mo, respectively. Burial of 36 mo or longer reduced seed viability to < 2%. The relationship between Benghal dayflower seed viability and burial time was described by a sigmoidal regression model. In Florida, there was greater variability in Benghal dayflower seed viability than there was at the other locations. Seed viability at the first sampling date after 2 mo of burial was 63%. Although there were fluctuations during the first 24 mo, the regression model indicated approximately 60% of seed remained viable. After 34 mo of burial, seed viability was reduced to 46% and then rapidly fell to 7% at 39 mo, which was consistent with the decrease in seed viability at the other locations. Although there is a physical dormancy imposed by the seed coat of Benghal dayflower, which has been detected in previous studies, it appears that a decline in buried seed viability to minimal levels occurs within 39 to 48 mo in the southeastern United States, suggesting that management programs must prevent seed production for at least four growing seasons to severely reduce the Benghal dayflower soil seedbank.

Quantitative multiplexed strategies for human Lyme disease serological testing

2021 ◽  
pp. 153537022110034
Author(s):  
Eunice Chou ◽  
Armond Minor ◽  
Nathaniel C Cady
Keyword(s):  
Lyme Disease ◽  
The United States ◽  
Disease Diagnosis ◽  
Response To Treatment ◽  
Serological Response ◽  
Serological Testing ◽  
Current State ◽  
Primary Means ◽  
Human Immune Response ◽  
Diagnostic Approaches

Lyme disease, which is primarily caused by infection with the bacterium Borrelia burgdorferi in the United States or other Borrelia species internationally, presents an ongoing challenge for diagnostics. Serological testing is the primary means of diagnosis but testing approaches differ widely, with varying degrees of sensitivity and specificity. Moreover, there is currently no reliable test to determine disease resolution following treatment. A distinct challenge in Lyme disease diagnostics is the variable patterns of human immune response to a plurality of antigens presented by Borrelia spp. during the infection. Thus, multiplexed testing approaches that capture these patterns and detect serological response against multiple antigens may be the key to prompt, accurate Lyme disease diagnosis. In this review, current state-of-the-art multiplexed diagnostic approaches are presented and compared with respect to their diagnostic accuracy and their potential for monitoring response to treatment.

Tropical Spiderwort (Commelina benghalensis): A Tropical Invader Threatens Agroecosystems of the Southern United States

2005 ◽  
Vol 19 (3) ◽  
pp. 501-508 ◽  
Author(s):  
Theodore M. Webster ◽  
Michael G. Burton ◽  
A. Stanley Culpepper ◽  
Alan C. York ◽  
Eric P. Prostko
Keyword(s):  
United States ◽  
Crop Production ◽  
Management Strategies ◽  
The United States ◽  
Southern United States ◽  
Commelina Benghalensis ◽  
Rapid Spread ◽  
Lack Of Control ◽  
Environmental Limits ◽  
Benghal Dayflower

Tropical spiderwort (more appropriately called Benghal dayflower) poses a serious threat to crop production in the southern United States. Although tropical spiderwort has been present in the United States for more than seven decades, only recently has it become a pest in agricultural fields. Identified as an isolated weed problem in 1999, tropical spiderwort became the most troublesome weed in Georgia cotton by 2003. Contributing to the significance of tropical spiderwort as a troublesome weed is the lack of control afforded by most commonly used herbicides, especially glyphosate. Vegetative growth and flower production of tropical spiderwort were optimized between 30 and 35 C, but growth was sustained over a range of 20 to 40 C. These temperatures are common throughout much of the United States during summer months. At the very least, it appears that tropical spiderwort may be able to co-occur with cotton throughout the southeastern United States. The environmental limits of tropical spiderwort have not yet been determined. However, the rapid spread through Georgia and naturalization in North Carolina, coupled with its tolerance to current management strategies and aggressive growth habit, make tropical spiderwort a significant threat to agroecosystems in the southern United States.

scholarly journals Adaptability of Pecan as a Species

HortScience ◽  
2005 ◽  
Vol 40 (5) ◽  
pp. 1175-1189 ◽  
Author(s):  
Darrell Sparks
Keyword(s):  
Seed Germination ◽  
Nutrient Uptake ◽  
Soil Profile ◽  
Growing Season ◽  
Freeze Tolerance ◽  
The United States ◽  
Sympatric Species ◽  
Southern Limit ◽  
Geographical Regions ◽  
Selection For

Pecan [Carya illinoinensis (Wangenh.) C. Koch] is indigenous to the Mississippi River drainage system of the United States. Climate in the native pecan region ranges from humid to semiarid and from mild to harsh winters. Rainfall is bimodal with peaks in March to April and in August to September. Pecan is site specific and is the climax tree species on loamy, well drained, first bottom river land with a relatively high water table. Detrimental effects from pecan's shade intolerance from its more vigorous, sympatric species are minimized as these species are specific to differ sites. Pecan's deep and phreatophytic rooting habit ensures soil moisture during drought periods and facilitates pecan's survival in semiarid regions. Root development in the humus-surface layer ensures nutrient uptake from the most nutrient rich layer of the soil and, when the lower soil profile is saturated, aeration for the roots and water and nutrient uptake. The bimodal rain pattern replenishes soil profile moisture and its timing ensures seed germination, stand establishment, well-developed seed, and minimal drought stress. Natural selection for freeze tolerance and for minimum fruit development time allows survival in areas with harsh winters and short growing seasons. Regulation of seed germination and budbreak by heating and chilling results in pecan being native in cold and warm climates, greatly increasing the native range. The northern limit for pecan is dictated by heat units; the southern limit is restricted by lack of bimodal rains and vivipary. Reproductive stress is caused by the high lipid content of seed, but is counteracted by a long juvenile growth period of the seedling, by a small nut size and low percentage kernel, and by “off” production years of the tree. Nut and percentage kernel decrease as the growing season decreases which contributes to species survival in geographical regions with a short growing season. Selection for small nuts with low percentage kernel is enhanced by predators. Tree reserves are depleted by heavy production during “on” years and are replenished during “off”years. Perpetuation of pecan forests is apparently from sib/half sib seedlings following predator satiation while dissemination into new areas may be mainly by predators. Pecan and its pests successfully co-exist. Major defense against fruit feeders is escape in time, leaf feeders by biological associations and accommodation, and leaf diseases by confrontation. Heterozygous progenies from cross-pollination provide ample genetic diversity for continuous pecan selection to endure pressures imposed throughout a wide climatic range. Ecological adaptions within native pecan forests should be used in developing and maintaining commercial pecan orchards.

Influence of stratification, light, and planting depth on rabbitbrush seed germination and emergence

2014 ◽  
Vol 15 (2) ◽  
pp. 109-118
Author(s):  
S. L. Love ◽  
R. R. Tripepi ◽  
T. Salaiz
Keyword(s):  
Seed Germination ◽  
Planting Depth

Dormancy-breaking Studies on Echinacea angustifolia

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 456f-457 ◽  
Author(s):  
Ali O. Sari ◽  
Mario R. Morales ◽  
James E. Simon
Keyword(s):  
Native Americans ◽  
Seed Germination ◽  
Tap Water ◽  
The United States ◽  
Market Demand ◽  
Dormancy Breaking ◽  
Echinacea Angustifolia ◽  
Native Populations ◽  
Percent Germination ◽  
Dry Heating

Echinacea is a medicinal plant native to North America. It was used extensively by native Americans in the treatment of their ailments. It is presently one of the most popular medicinal plants in the United States. Its popularity has created a large market demand for the roots and foliage of the plant. The gathering of echinacea from the wild is leading to the reduction of native populations and the destruction of its genetic diversity. Cultivation of medicinal echinaceas is hindered by a low seed germination. Dormancy breaking studies were done on freshly harvested seeds of Echinacea angustifolia. Seed lots were placed under light at a constant temperature of 25 °C and at alternate temperatures of 25/15 °C for 14/10 h, respectively. Germination was more rapid and uniform and percent germination higher at 25 °C than at 25/15 °C. Seed tap-water soaking, dry heating, and sharp heating alteration did not increase germination. The application of 1.0 mM ethephon (2-chloroethylphosphoric acid) increased seed germination to 94% at 25 °C and 86% at 25/15 °C. Untreated seeds gave 65% germination at 25 °C and 11% at 25/15 °C. The application of 2500 mg·L–1 and 3500 mg·L–1 of GA to dry seeds and 2500 mg·L–1 to seeds that have been soaked under tap water and then dried increased germination to 82%, 83%, and 83% at 25 °C and 64%, 78%, and 64% at 25/15 °C, respectively.

scholarly journals Discovering Non-Invasive Biomarkers Predictive of Opioid Use Disorder Treatment Response

CNS Spectrums ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 173-173
Author(s):  
Amir Levine ◽  
Kelly Clemenza ◽  
Shira Weiss ◽  
Adam Bisaga ◽  
Erez Eitan ◽  
...  
Keyword(s):  
Treatment Response ◽  
Mononuclear Cells ◽  
Specific Treatment ◽  
The United States ◽  
Opioid Use Disorder ◽  
Response To Treatment ◽  
Post Translational Modification ◽  
Opioid Use ◽  
Peripheral Blood Mononuclear ◽  
Long Term Treatment

AbstractBackgroundOpioid use disorder (OUD) continues to be the driving force behind drug overdoses in the United States, killing nearly 47,000 people in 2018 alone. The increasing presence of deadlier fentanyl analogues in the heroin drug supply are putting users at a greater risk for overdose than ever before. Admissions to treatment programs for OUD have also nearly doubled since 2006, yet relapse rates remain high. In response to these alarming statistics, developing approaches to reduce overdose deaths has become an area of high priority. As it is not yet known which patients are most likely to benefit from a specific treatment, there is a dire need to utilize new molecular tools to guide precision medicine approaches and improve treatment outcomes. Here we describe a proof-of-concept study evaluating plasma-derived extracellular vesicle (EV) signatures and how they differ in patients who responded to two pharmacologically contrasting treatments for OUD: the μOR agonist methadone, and the μOR antagonist naltrexone.MethodsWe obtained blood samples from patients with OUD who remained abstinent from illicit opioids for at least 3 months during treatment with methadone (n=5) and naltrexone (n=5), as well as matched healthy controls (n=5). EVs were isolated from plasma and histones were isolated from peripheral blood mononuclear cells (PBMCs). EVs were then analyzed for lipid and histone post-translational modification (PTM) content using liquid chromatography-mass spectrometry. EV miRNA cargo was determined by RNA sequencing.ResultsWe found one lipid class and six miRNAs that differed significantly between the naltrexone group and the methadone and control groups. We also found that histone H3acK9acK14 was increasingly acetylated in PMBCs from both the methadone and naltrexone groups compared to controls.DiscussionNaltrexone, which is used in treatment of OUD and other substance use disorders as well as disorders of impulse control, was found to have multiple potential corresponding molecular signatures that can be identified after long-term treatment. It remains to be seen if these markers can also be a good predictor for treatment response. In addition, significant gender differences in EV content are found between men and women with OUD, which supports the importance of examining changes in response to treatment in a gender informed way.

scholarly journals Response to treatment with intra-articular triamcinolone hexacetonide and triamcinolone acetonide in oligo articular juvenile idiopathic arthritis

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Rana Harhay ◽  
Wajiha Jeelani ◽  
Barbine Tchamba Agbor Agbor ◽  
Teresa Hennon ◽  
Brian H. Wrotniak ◽  
...  
Keyword(s):  
Juvenile Idiopathic Arthritis ◽  
Side Effects ◽  
Triamcinolone Acetonide ◽  
The United States ◽  
Response To Treatment ◽  
Joint Injection ◽  
Triamcinolone Hexacetonide ◽  
Active Arthritis ◽  
General Response

Abstract Background Oligo-articular juvenile idiopathic arthritis (Oligo JIA) is the most common subtype of juvenile idiopathic arthritis. Intra-articular corticosteroid (IAC) injection is a mainstay treatment of oligo JIA providing pain relief, improving mobility and preventing further joint destruction in the majority of patients. In 2015, production of triamcinolone hexacetonide (TH) an intra-articular corticosteroid was discontinued in the United States leading to use of triamcinolone acetonide (TA) as an alternative. In this study, we compared response to treatment in children with oligo JIA who underwent therapy with intra-articular TA and TH injection. Methods Our study is a retrospective chart review of children with oligo JIA who were treated with IAC injections with TH between January 2012 and June 2015 and TA between J uly 2015 and December 2018. The two groups were followed at John R. Oishei Children’s Hospital of Buffalo and were evaluated for response to treatment, side effects and predictors of response including duration of disease before treatment, erythrocyte sedimentation rate (ESR), and c-reactive protein (CRP). Response to treatment was defined as at least 6 months follow up without evidence of active arthritis in injected joints. Patients were considered to be non-responders if they continued to show active arthritis during their first follow up after joint injection. The primary objective was to evaluate whether there was a significant difference in rate of response between TH and TA. Results Forty-nine patients, 38 female and 11 male with oligo JIA were included in the study. The average age was 6.7 years. A total of 111 joints were injected includin g 78 knees, 13 ankles, 9 wrists, 4 hips, 4 elbows, 2 TMJ and one subtalar joint. In the TA group, 49% (29/59) did not show response to injection compared to 27% (14/52) in the TH group. After 6 months, response rates were better for individuals injected with TH compared to TA (73% vs. 51%). In general, response to intra-articular TH was superior to TA with P = .016 using chi-square test of independence. This difference in outcome was not influenced by other variables such as duration of illness before treatment (P value 0.784) or elevated ESR and CRP. No difference in side effects between the two groups were noted. Conclusion Our results in conjunction with prior published data suggests that TH intra-articular joint injection in oligo JIA is superior to TA, although future controlled trials are necessary for confirmation. An effective, long lasting treatment can have a great impact on the outcome of these children.

Evaluation of the phytotoxicity of 2,4-diacetylphloroglucinol and Pseudomonas brassicacearum Q8r1-96 on different wheat cultivars

2021 ◽  
Author(s):  
Mingming Yang ◽  
Linda S Thomashow ◽  
David M Weller
Keyword(s):  
Seed Germination ◽  
Pacific Northwest ◽  
Root Colonization ◽  
The United States ◽  
Wheat Cultivars ◽  
The Pacific ◽  
Root Necrosis ◽  
Growth Promoting ◽  
Pseudomonas Brassicacearum

Pseudomonas brassicacearum Q8r1-96 and other 2,4-diacetylphloroglucinol (DAPG)-producing pseudomonads of the Pseudomonas fluorescens complex possess both biocontrol and growth-promoting properties and play an important role in suppression of take-all of wheat in the Pacific Northwest (PNW) of the United States. However, P. brassicacearum can also reduce seed germination and cause root necrosis on some wheat cultivars. We evaluated the effect of Q8r1-96 and DAPG on the germination of 69 wheat cultivars that have been or currently are grown in the PNW. Cultivars varied widely in their ability to tolerate P. brassicacearum or DAPG. The frequency of germination of the cultivars ranged from 0 to 0.87 and from 0.47 to 0.90 when treated with Q8r1-96 and DAPG, respectively. There was a significant positive correlation between the frequency of germination of cultivars treated with Q8r1-96 in assays conducted in vitro and in the greenhouse. The correlation was greater for spring than for winter cultivars. In contrast, the effect of Q8r1-96 on seed germination was not correlated with that of DAPG alone, suggesting that DAPG is not the only factor responsible for the phytotoxicity of Q8r1-96. Three wheat cultivars with the greatest tolerance and three cultivars with the least tolerance to Q8r1-96 were tested for their ability to support root colonization by strain Q8r1-96. Cultivars with the greatest tolerance supported significantly greater populations of strain Q8r1-96 than those with the least tolerance to the bacteria. Our results show that wheat cultivars differ widely in their interaction with P. brassicacearum and the biocontrol antibiotic DAPG.

Seed germination biology of sweet acacia (Vachellia farnesiana) and response of its seedlings to herbicides

Weed Science ◽  
2021 ◽  
pp. 1-19
Author(s):  
Bhagirath S. Chauhan ◽  
Shane Campbell ◽  
Victor J. Galea
Keyword(s):  
Sodium Chloride ◽  
Seed Germination ◽  
Development Stage ◽  
Hot Water ◽  
Control Treatment ◽  
Similar Species ◽  
Weed Species ◽  
Physical Dormancy ◽  
Seed Biology ◽  
Wide Range

Abstract Sweet acacia [Vachellia farnesiana (L.) Willd.]is a problematic thorny weed species in several parts of Australia. Knowledge of its seed biology could help to formulate weed management decisions for this and other similar species. Experiments were conducted to determine the effect of hot water (scarification), alternating temperatures, light, salt stress, and water stress on seed germination of two populations of V. farnesiana and to evaluate the response of its young seedlings (the most sensitive development stage) to commonly available POST herbicides in Australia. Both populations behaved similarly to all the environmental factors and herbicides; therefore, data were pooled over the populations. Seeds immersed in hot water at 90 C for 10 min provided the highest germination (88%), demonstrating physical dormancy in this species. Seeds germinated at a wide range of alternating day/night temperatures from 20/10 C (35%) to 35/25 C (90%) but no seeds germinated at 15/5 C. Germination was not affected by light, suggesting that seeds are nonphotoblastic and can germinate under a plant canopy or when buried in soil. Germination was not affected by sodium chloride concentrations up to 20 mM and about 50% of seeds could germinate at 160 mM sodium chloride, suggesting its high salt tolerance ability. Germination was only 13% at −0.2 MPa osmotic potential and no seeds germinated at −0.4 MPa, suggesting that V. farnesiana seeds may remain ungerminated until moisture conditions have become conducive for germination. A number of POST herbicides, including 2,4-D + picloram, glufosinate, paraquat and saflufenacil, provided >85% control of biomass of young seedlings compared with the nontreated control treatment. Knowledge gained from this study will help to predict the potential spread of V. farnesiana in other areas and help to integrate herbicide use with other management strategies.

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