Temperature and dormancy-breaking treatments: germination of endemic and geographically restricted herbaceous perennials

2006 ◽  
Vol 54 (4) ◽  
pp. 349 ◽  
Author(s):  
Anne Cochrane ◽  
Robin Probert
Keyword(s):  
Surgical Treatment ◽  
Surgical Excision ◽  
Potassium Nitrate ◽  
Dormancy Breaking ◽  
Physical Dormancy ◽  
Herbaceous Perennials ◽  
Treatment Conditions ◽  
Effects Of Temperature ◽  
Pre Treatment ◽  
Mean Time

This paper describes the effects of temperature and simple or multiple dormancy-breaking treatments (potassium nitrate, surgical treatment, gibberellic acid (GA3), after-ripening at 45°C and nitrogen dioxide gas) on germination of five endemic and geographically restricted herbaceous perennials (Apium prostratum Vent. subsp. phillipii Keighery ms, Goodenia stenophylla F.Muell., Marianthus granulatus (Turcz.) Benth, Myriocephalus suffruticosus Benth. and Velleia foliosa (Benth.) K.Krause) from the species-rich south-west of Western Australia. Except for seeds of A. prostratum that were non-dormant, seeds were partially dormant or fully dormant when incubated without pre-treatment at three temperatures (15, 20 and 25/10°C). Low germination (≤52%) was detected in M. granulatus under the best identified conditions, and seeds of G. stenophylla showed little to no response to any germination cue. In M. granulatus, M. suffruticosus and V. foliosa combinations of treatments were found that led to enhanced germination and in the case of V. foliosa, germination was not significantly different from a tetrazolium test of viability when seeds were surgically treated and then incubated with KNO3. Although none of the species studied exhibited physical dormancy, surgical excision of the seed coat in the vicinity of the embryo featured in the most successful combination of treatments in every case. Whilst seeds of M. granulatus responded positively to surgical treatment, after-ripening of seeds at 45°C for 2, 4 or 6 weeks did not increase either speed or final germination compared with other treatments. The mean time to germinate (MTG) ranged from 12.6 days (A. prostratum ssp. phillipii) to 46.5 days (G. stenophylla) under the best treatment conditions for each species.

Comparison of pre-treatments for inducing germination in highly dormant wheat genotypes

2003 ◽  
Vol 83 (4) ◽  
pp. 729-735 ◽  
Author(s):  
M. A. Matus-Cádiz ◽  
P. Hucl
Keyword(s):  
Seedling Growth ◽  
Biomass Yield ◽  
Triticum Aestivum L ◽  
Potassium Nitrate ◽  
Dormancy Breaking ◽  
Yield Data ◽  
Breeding Populations ◽  
Breaking Dormancy ◽  
Seedling Length ◽  
Pre Treatment

An effective dormancy-breaking method may be of interest to wheat (Triticum aestivum L.) breeders selecting for increased seed dormancy prior to advancing their populations in greenhouse grow-outs. The objective of this study was to identify an effective pre-treatment for breaking dormancy in wheat that did not result in seedling etiolation. In 2000, eight dormant (W98616, line 211, EMDR-4, EMDR-9, EMDR-14, RL4137, Columbus, and AC Domain) and one nondormant line (Roblin) were grown at two locations in Saskatchewan. Seeds were: (i) stored for zero to 21 wks at 24°C before incubating at 20°C for 7 d; (ii) incubated at 5, 10, 15, 20, and 25°C for 14 d; and (iii) treated with gibberellic acid (GA3) (0.0006 and 0.0014 M), potassium nitrate (KNO3) (0.01 and 0.02 M), chilling, heating, chilling with 0.01 M KNO3, and heating with 0.01 M KNO3 before incubating at 10°C for 14 d. Seedling growth was observed in a duplicated growth chamber experiment. Seedling length, first inter-node length, and biomass yield data were collected from plants grown from seeds treated with four effective pretreatments. Data were subjected to an ANOVA. Six to 18 weeks of storage at 24°C were required to break the dormancy (≥ 95% germination) in dormant genotypes. Incubation at 10°C was the most effective temperature for promoting germination in dormant seeds after 10d of testing. Four pre-treatments including 0.0006 M GA3, 0.0014 M GA3, chilling with 0.01 M KNO3, and heating with 0.01 M KNO3 led to ≥ 95% germination within 10 d of testing. Only GA3 treatments were associated with etiolated seedling growth. Heating with 0.01 M KNO3 or chilling with 0.01 M KNO3, applied before incubating at 10°C in darkness, may be of interest to breeders selecting for increased dormancy before advancing breeding populations in greenhouse grow-outs. Key words: Triticum, dormancy, nitrate, chilling, heating, etiolated seedling

Dormancy-breaking and germination requirements for seeds of Acacia papyrocarpa, Acacia oswaldii and Senna artemisioides ssp.×coriacea, three Australian arid-zone Fabaceae species

2014 ◽  
Vol 62 (7) ◽  
pp. 546 ◽  
Author(s):  
Leanne M. Pound ◽  
Phillip J. Ainsley ◽  
José M. Facelli
Keyword(s):  
Arid Zone ◽  
South Australia ◽  
Dormancy Breaking ◽  
Physical Dormancy ◽  
Dry Heat ◽  
Seed Mortality ◽  
Wet Heat ◽  
Pre Treatment ◽  
Unpredictable Environment ◽  
Germination Requirements

Physical dormancy is common in seeds of arid-land legumes. Improved understanding of germination requirements of hard-seeded species will further our understanding of arid lands and aid restoration projects. We studied the germination responses of Acacia papyrocarpa (Benth.), A. oswaldii (F.Muell) and Senna artemisioides (Gaudich. ex DC.) Randell ssp. × coriacea (Benth.) Randell from a chenopod shrubland in South Australia. Imbibition testing indicated that all three species had physical dormancy, but the proportion of dormant seeds was lower in A. oswaldii. This corresponded to a thinner testa in this species. Mechanisms tested to scarify seeds included mechanical scarification and different durations of wet or dry heat. Mechanically scarified seeds germinated readily, reaching maximum numbers in 10–15 days, independently of incubation temperatures, with the exception of S. artemisioides seeds, which germinated at a slower rate in cooler temperatures. Overall, wet heat was more effective than dry heat to alleviate physical dormancy, whereas dry heat in some cases resulted in seed mortality. On the basis of these results, it is recommended that seeds of A. papyrocarpa and S. artemisoides be pretreated with wet heat in future restoration programs. No pre-treatment is required for dormancy loss in A. oswaldii seeds. The different responses of seeds of these species suggest that their populations have varying strategies for persistence in this unpredictable environment.

scholarly journals Exogenous 5-azaCitidine accelerates flowering and external GA3 increases ornamental value in Iranian Anemone accessions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vahideh Yari ◽  
Zeynab Roein ◽  
Atefeh Sabouri
Keyword(s):  
Morphological Characteristics ◽  
Flower Longevity ◽  
Cut Flowers ◽  
Stem Height ◽  
Flowering Stage ◽  
Potted Plants ◽  
Dormancy Period ◽  
Treatment Conditions ◽  
Number Of Leaves ◽  
Pre Treatment

AbstractThe Anemone genus is a tuberous geophyte which undergoes a dormancy period during unfavorable environmental conditions for growth. Five species of the Anemone genus naturally grow in several regions of Iran. The diverse uses of Anemone in gardens for landscaping, cut flowers, and potted plants indicate its high ornamental potential. Its dormancy and flowering are influenced by various factors. The present paper was conducted to explore the flowering behavior of Anemone accessions in response to different pre-treatments. For this purpose, tubers of 18 Anemone accessions (A. coronaria and A. biflora) were collected from natural regions of six provinces in Iran. These tubers were subjected to different conditions of non-chilling (20 °C, 90 days), chilling (4 °C, 90 days), GA3 (150 mgL-1; 24 h), and 5-azaCitidine (5-azaC; 40 µM; 24 h) prior to the cultivation. Most of the accessions were able to enter the flowering stage without chilling. The shortest period for the sprouting of tubers (16.89 ± 7.83 days) belonged to 5-azaC pre-treatment. In addition, this treatment accelerated the flowering time (about 30 days earlier) and diameter of the stem, bud, and flower. Morphological characteristics, such as stem height, number of leaves, bud, and petal and the longevity of flowers on the plant were significantly affected by GA3 pre-treatment. Our results indicated a positive correlation between flower length, stem height, and stem diameter with flower longevity under different pre-treatment conditions. The present study demonstrated that accessions Anm3, Anm12, and Anm18 had ornamental values higher than the population mean across four conditions.

scholarly journals Adjuvant HPV Vaccination to Prevent Recurrent Cervical Dysplasia after Surgical Treatment: A Meta-Analysis

Vaccines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 410
Author(s):  
Violante Di Donato ◽  
Giuseppe Caruso ◽  
Marco Petrillo ◽  
Evangelos Kontopantelis ◽  
Innocenza Palaia ◽  
...  
Keyword(s):  
Surgical Treatment ◽  
Meta Analysis ◽  
Hpv Vaccination ◽  
Cervical Dysplasia ◽  
Reduction Rate ◽  
Intraepithelial Neoplasia ◽  
Surgical Excision ◽  
Inclusion Criteria ◽  
Mean Differences ◽  
The Impact

Objective: The aim of this meta-analysis was to discuss evidence supporting the efficacy of adjuvant human papillomavirus (HPV) vaccination in reducing the risk of recurrent cervical intraepithelial neoplasia (CIN) 2 or greater after surgical treatment. Methods: A systematic literature search was performed for studies reporting the impact of HPV vaccination on reducing the risk of recurrence of CIN 2+ after surgical excision. Results were reported as mean differences or pooled odds ratios (OR) with 95% confidence intervals (95% CI). Results: Eleven studies met the inclusion criteria and were selected for analysis. In total, 21,310 patients were included: 4039 (19%) received peri-operational adjuvant HPV vaccination while 17,271 (81%) received surgery alone. The recurrence of CIN 2+ after treatment was significantly lower in the vaccinated compared with the unvaccinated group (OR 0.35; 95% CI 0.21–0.56; p < 0.0001). The recurrence of CIN 1+ after treatment was significantly lower in the vaccinated compared with the unvaccinated group (OR 0.51; 95% CI 0.31–0.83; p = 0.006). A non-significant trend of reduction rate of HPV persistence was observed in the vaccinated compared with the unvaccinated cohorts (OR was 0.84; 95% CI 0.61–1.15; p = 0.28). Conclusions: HPV vaccination, in adjuvant setting, is associated with a reduced risk of recurrent CIN 1+ and CIN 2+ after surgical treatment.

A disease-based evaluation of lung cancer care quality in a community healthcare system.

2021 ◽  
Vol 39 (28_suppl) ◽  
pp. 251-251
Author(s):  
Meghan Brooke Taylor ◽  
Meredith Ray ◽  
Nicholas Faris ◽  
Matthew Smeltzer ◽  
Carrie Fehnel ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Quality Improvement ◽  
Surgical Treatment ◽  
Healthcare System ◽  
Cancer Care ◽  
Care Quality ◽  
Nodal Points ◽  
Diagnostic Biopsy ◽  
Pre Treatment ◽  
Non Surgical Treatment

251 Background: Lung cancer care is complex, but, for quality improvement, can be simplified into five ‘nodal points’: lesion detection, diagnostic biopsy, radiologic staging, invasive staging, and treatment. We previously demonstrated great heterogeneity in passage through these nodal points in patients who received surgical resection for lung cancer in our healthcare system. However, examining only surgical patients may underestimate the enormity of the opportunity for quality improvement. With the aim of identifying quality gaps in pre-treatment evaluation for lung cancer, we evaluated the flow of care through these nodal points within a community-based healthcare system. Methods: We classified lung cancer care procedures received by all suspected lung cancer patients treated within the Multidisciplinary Thoracic Oncology Program at Baptist Cancer Center, Memphis TN between 2014 and 2019, into five nodal points. We compared the frequency of, and time intervals between, nodal points among patients receiving surgical, nonsurgical (chemotherapy/radiation), or no definitive treatment, using Chi-square or Kruskal Wallis tests, where appropriate. Results: Of 1304 eligible patients: 11% had no pre-treatment diagnostic procedure, 20% no PET/CT, and 39% no invasive staging. 39% of patients underwent surgical resection, 51% received non-surgical treatment, and 10% received no treatment. Patients who had surgery were less likely than those who had non-surgical treatment to get a diagnostic test, radiologic staging, and invasive staging (Table). Patients who had non-surgical treatment were more likely to pass through all five nodal points (50% v 68%, p<0.0001). The median (IQR) duration from initial lesion identification to treatment (n=1126) was 77 days (45-190); 27 days (10-90) from lesion identification to diagnostic biopsy (n=1115); and 38 days (26-63) from diagnostic biopsy to treatment (n=1041). Patients who had surgery received less timely care than those who had non-surgical or no treatment: median 122 v 66 v 68 days from lesion identification to treatment; 40 v 21 v 29 days from lesion identification to diagnostic biopsy; 46 v 38 v 31 days from diagnostic biopsy to treatment (p<0.0001 all comparisons). Conclusions: Quality improvement initiatives within our healthcare system, such as the establishment of a coordinated multidisciplinary program, enhanced care quality over previous benchmarks. Despite improvements, lung cancer patients who had surgery received less frequent and less timely pre-treatment evaluation than those without surgery. Implementing a standardized cancer care pathway from diagnosis to surgery could help to reduce variations in optimal care delivery.[Table: see text]

scholarly journals Effects of Different Pretreatments and Seed Coat on Dormancy and Germination of Seeds of Senna obtusifolia (L.) H.S. Irwin & Barneby (Fabaceae)

2016 ◽  
Vol 8 (2) ◽  
pp. 77
Author(s):  
Stephen I. Mensah ◽  
Chimezie Ekeke
Keyword(s):  
Sulfuric Acid ◽  
Seed Dormancy ◽  
Water Uptake ◽  
Seed Coat ◽  
Critical Factor ◽  
Potassium Nitrate ◽  
Ex Situ ◽  
Mechanical Resistance ◽  
Physical Dormancy ◽  
Senna Obtusifolia

<p class="1Body">The seed dormancy of <em>Senna obtusifolia</em> was investigated through various methods, namely pretreatments in concentrated sulfuric acid, 2% potassium nitrate (KNO<sub>3</sub>), 99% ethanol, 99% methanol, and in hydrogen perioxide; examination of the seed coverings; and the determination of water uptake by the seeds in order to ascertain the most effective technique for breaking dormancy and also determine the dormancy type. The results showed that sulfuric acid treatment recorded the highest germination (100%); followed by 2% hydrogen peroxide treatment (24%) in 15minutes immersion. The methanol and ethanol pretreatments gave 18.33% and 16.5% germinations respectively. Pretreatment in 2% potassium nitrate gave the lowest germination (8.50%), while the intact seeds of <em>S. obtusifiolia</em> (control) gave 0% germination. The anatomy of the seed coat indicated the presence of hard, thickened and specialized cells of cuticle, macrosclereids, osteoscereids, and disintegrated parenchyma layers. The water uptake of intact seeds was low (13.5%) after 24 hr imbibitions. These findings revealed that the seed coat acts as barrier to germination by preventing water absorption, possibly gaseous diffusion in and out of the seed and conferring mechanical resistance to the protrusion of embryo. Pretreatments, such as immersion in H<sub>2</sub>SO<sub>4 </sub>will soften the seed coat and permit germination. Seed dormancy in <em>S. obtusifolia </em>can be considered of physical nature and classified as physical dormancy. The results obtained in this study may serve as useful information in the production and improvement of <em>S. obtusifolia </em>seedlings, as knowledge on seed dormancy and germination is a critical factor and requirements to the understanding of the propagation of this plant either in situ or ex-situ, in view of the economic potentials/attributes of this species.</p>

Removal Efficiency of Three Cold-Climate Constructed Wetlands Treating Domestic Wastewater: Effects of Temperature, Seasons, Loading Rates and Input Concentrations

1999 ◽  
Vol 40 (3) ◽  
pp. 273-281 ◽  
Author(s):  
Trond Mæhlum ◽  
Per Stålnacke
Keyword(s):  
Organic Matter ◽  
Constructed Wetlands ◽  
Domestic Wastewater ◽  
Cold Climate ◽  
Treatment Efficiency ◽  
Loading Rates ◽  
P Sorption ◽  
Percentage Points ◽  
Effects Of Temperature ◽  
Pre Treatment

This paper outlines the influence of temperature, flow rate and input concentrations on the treatment efficiency of organic matter and nutrients in constructed wetlands (CWs). Three integrated 10 PE systems with horizontal subsurface flow (HSF) treating domestic wastewater are described. Particular attention is devoted to: (1) aerobic pre-treatment in vertical-flow filters, (2) filter media with high phosphorus (P) sorption capacity, and (3) the treatment efficiency during winters. Aerobic pre-treatment followed by CW units including P sorption media removed most organic matter (BOD&gt; 75%), P (&gt; 90%) and total and ammonia N (40-80%). P retention was relatively stable in wetland filters, both with lightweight aggregates and ferruginous sand during 3-6 years of monitoring. Iron-rich sand from Bsh and Bs horizons of ferro-humic podzols was efficient for P sorption, but removal efficiencies of COD, TOC and SS were negative. The differences in efficiency between cold and warm periods were less than 10 percentage points for all parameters. It is anticipated that temperature effects are partially compensated by the large hydraulic retention time. The findings suggest that HSF systems do not require vegetation.

scholarly journals Treatment of Facial Nevi with Ideal Design and Splitting Technique

2021 ◽  
Author(s):  
Qiang Sun ◽  
Jiayan Guo ◽  
Siyu Liu ◽  
Mengru Zhu ◽  
Jingyi Feng ◽  
...  
Keyword(s):  
Surgical Treatment ◽  
Plastic Surgery ◽  
Surgical Excision ◽  
Added Value ◽  
Complete Excision ◽  
Splitting Technique ◽  
Surgical Methods ◽  
Serial Excision ◽  
Non Surgical Treatment

Abstract Background: The treatment of nevi includes surgical treatment and non-surgical treatment. Non-surgical treatment has many defects in the clinic, whereas surgical treatment is applicable to any type of nevi. However, there is no unified standard for surgical methods. Methods: Patients with facial nevi ( width ≤4 cm) and high requirements for beauty were included. Preoperatively, incision design and resection range based on the recommended wrinkles or folds of each region and principle of plastic surgery. Intraoperatively, a nevus flap was formed, and then equally divided by splitting technique. After the splitting nevus flap was resected, suture without tension was performed. Results: 21 patients underwent surgical excision. 14 patients underwent complete excision, while 7 patients underwent serial excision. The patients were satisfied with the appearance, local sensations were normal, and there were no secondary deformities of the surrounding facial organs without recurrence.Conclusion: This method is of added value, which achieved by the correct assessment of the size and location of facial nevi and designed according to the reference marks in each region and complete or serial excision.

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