scholarly journals Dormancy Breaking inOrmosia arboreaSeeds

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Edilma Pereira Gonçalves ◽  
Franklim Sales de Jesus Soares ◽  
Sérgio dos Santos Silva ◽  
Débora de Souza Tavares ◽  
Jeandson Silva Viana ◽  
...  

Ormosia arboreais a tree species planted in urban areas and used to restore degraded areas. Its seeds are dormant and propagation is difficult. This study compares different dormancy breaking methods and physiological seed quality and seedling production. The seeds were germinated in sand in the laboratory of the Universidade Estadual de Santa Cruz, Ilhéus, Bahia, Brazil. The following dormancy breaking treatments were applied: control (intact seeds), 100°C water immersion; boiling water immersion followed by 24 hours of soaking; scarification with number 100 and number 50 sandpaper opposite from root emergence; sulfuric acid immersion for 1 hour, 50, 45, and 30 minutes. Seed immersion in 100°C and boiling water did not break the dormancy. The study species showed a greater vigor of seedling when its seeds were submitted to treatments associated with tegument rupturing by sandpaper or sulfuric acid. On the other hand, seed scarification with sulfuric acid for 1 hour, 50, 45, and 30 minutes or sandpaper favored seed germination and vigor.

2006 ◽  
Vol 20 (25n27) ◽  
pp. 3611-3616 ◽  
Author(s):  
B. WITHY ◽  
M. HYLAND ◽  
B. JAMES

Chemical pretreatments are often used to improve the adhesion of coatings to aluminium. XPS and AFM were used to study the effect of these pretreatments on the surface chemistry and morphology of Al 5005. Four pretreatments were investigated, an acetone degrease, boiling water immersion, and two sulphuric acid etches, FPL and P2. Degreasing had no affect on surface morphology and simply added to the adventitious carbon on the surface. Boiling water immersion produced a chemically stable pseudo-boehmitic surface that was quite porous. The acid etches produced porous pitted surfaces similar to each other but significantly different to the other surfaces. The surface chemistry of the acid etched surfaces was variable and dependant on atmospheric conditions on removal from etch due to the very active surface that the etch produced.


2014 ◽  
Vol 36 (3) ◽  
pp. 318-325 ◽  
Author(s):  
Aparecida Leonir da Silva ◽  
Denise Cunha Fernandes dos Santos Dias ◽  
Liana Baptista de Lima ◽  
Glaucia Almeida de Morais

Ormosia arborea, a Leguminosae, presents seeds with tegumentary dormancy. The purpose of this study was to evaluate the efficiency of dormancy breaking methods, characterize seeds obtained from different mother plants, and to determine the best period to collect Ormosia arborea seeds. The seeds were harvested from mother plants in two different periods (June and August/2011). The seeds were then subjected to biometrical analyses, determination of moisture content and germination tests. Determination of the soaking curve and evaluation of the dormancy breaking methods were performed using the seeds collected in the second period. The soaking curve confirmed the tegumentary dormancy, and the chemical scarification for 15 minutes was the more adequate procedure to overcome this dormancy. The biometry revealed average values higher than those on literature, and there was difference between both harvesting periods. The mass correlates with the other evaluated parameters, and can be indicated for selecting seeds for seedling production. The two harvesting periods of Ormosia arborea seeds were considered appropriated for seed supplying, due to the high germination potential. Nevertheless, the best period for harvesting is when fruits are already opened, mature, and with low moisture content (no additional drying time needed), what hinders the occurrence of fungi.


2020 ◽  
Vol 13 (1) ◽  
pp. 37
Author(s):  
Luca Pulvirenti ◽  
Marco Chini ◽  
Nazzareno Pierdicca

A stack of Sentinel-1 InSAR data in an urban area where flood events recurrently occur, namely Beletweyne town in Somalia, has been analyzed. From this analysis, a novel method to deal with the problem of flood mapping in urban areas has been derived. The approach assumes the availability of a map of persistent scatterers (PSs) inside the urban settlement and is based on the analysis of the temporal trend of the InSAR coherence and the spatial average of the exponential of the InSAR phase in each PS. Both interferometric products are expected to have high and stable values in the PSs; therefore, anomalous decreases may indicate that floodwater is present in an urban area. The stack of Sentinel-1 data has been divided into two subsets. The first one has been used as a calibration set to identify the PSs and determine, for each PS, reference values of the coherence and the spatial average of the exponential of the interferometric phase under standard non-flooded conditions. The other subset has been used for validation purposes. Flood maps produced by UNOSAT, analyzing very-high-resolution optical images of the floods that occurred in Beletweyne in April–May 2018, October–November 2019, and April–May 2020, have been used as reference data. In particular, the map of the April–May 2018 flood has been used for training purposes together with the subset of Sentinel-1 calibration data, whilst the other two maps have been used to validate the products generated by applying the proposed method. The main product is a binary map of flooded PSs that complements the floodwater map of rural/suburban areas produced by applying a well-consolidated algorithm based on intensity data. In addition, a flood severity map that labels the different districts of Beletweyne, as not, partially, or totally flooded has been generated to consolidate the validation. The results have confirmed the effectiveness of the proposed method.


2021 ◽  
Vol 13 (10) ◽  
pp. 5411
Author(s):  
Elisabeth Bloder ◽  
Georg Jäger

Traffic and transportation are main contributors to the global CO2 emissions and resulting climate change. Especially in urban areas, traffic flow is not optimal and thus offers possibilities to reduce emissions. The concept of a Green Wave, i.e., the coordinated switching of traffic lights in order to favor a single direction and reduce congestion, is often discussed as a simple mechanism to avoid breaking and accelerating, thereby reducing fuel consumption. On the other hand, making car use more attractive might also increase emissions. In this study, we use an agent-based model to investigate the benefit of a Green Wave in order to find out whether it can outweigh the effects of increased car use. We find that although the Green Wave has the potential to reduce emissions, there is also a high risk of heaving a net increase in emissions, depending on the specifics of the traffic system.


Author(s):  
Marika Vogelzang

In this study I determined the effectiveness of pollinator gardens by testing if visitation rate and diversity of flower-visiting insects is higher in pollinator gardens compared to other ornamental plantings. I observed pollinator visitation for individual plant taxa, per unit area, in three different pollinator gardens, eight ornamental gardens and eight ornamental planters on the Queen’s University campus in Kingston, Ontario, Canada. Visitation was about 4- times higher in pollinator gardens compared to the other two ornamental garden types and visitor richness (the number of types of pollinators) in pollinator gardens was about 6- times higher compared to ornamental gardens, and about 3- times higher compared toornamental planters. The results of this study conclude that the planting of pollinator gardens is an effective way of supporting pollinator populations in urban areas.


2011 ◽  
Vol 13 (4) ◽  
pp. 507-511 ◽  
Author(s):  
J.M. Vasconcelos ◽  
M.A. Rodrigues ◽  
S.C. Vasconcelos Filho ◽  
J.F. Sales ◽  
F.G. Silva ◽  
...  

"Quina" (Strychnos pseudoquina A. St. Hil) is a medicinal plant species from the Brazilian Cerrado. As its seeds show dormancy, they were subjected to the treatments pre-cooling at 5ºC during 7 days, pre-heating at 40ºC during 7 days, pre-soaking in sulfuric acid PA during 5 and 15 min, pre-soaking in boiling water during 5 and 15 min, pre-soaking in 100 and 200 ppm gibberellic acid during 48 h, pre-soaking in distilled water during 24 and 48 h, and mechanical scarification to break dormancy. Counts were daily conducted from the 2nd day after the experiment implementation until the germination stabilization at the 65th day. The germination speed index (GSI) and the germination percentage were evaluated. Germination rates above 96% were reached in seeds pre-soaked in water during 48 h and substrate moistened with water or KNO3.


2019 ◽  
Author(s):  
Ricardo A. Buriti ◽  
Wayne Hocking ◽  
Paulo P. Batista ◽  
Igo Paulino ◽  
Ana R. Paulino ◽  
...  

Abstract. This paper is about a study of diurnal tides on meteor wind observed simultaneously by two meteor radars sited on equatorial region. The radar are located in Santa Cruz (10.3° N, 85.6° W), Costa Rica (hereafter CR) and in São João do Cariri (7.4° S, 36.5° W), Brazil (hereafter CA). The distance between them is 5800 km. Harmonic analysis was used to get information of amplitude and phase (hour of peak amplitude) of diurnal, semidiurnal and terdiurnal tides between 82 and 98 km of height. The period of observation was from April 2005 to January 2006. The results were compared to GSWM00 model. In general, seasonal agreement between observation and model was satisfactory to zonal and meridional amplitudes. Values of zonal and meridional amplitudes from November to January to CR were very different of GSWM00. Peak of zonal amplitude (~ 25 m/s) to CR was observed in September and December between 90 and 94 km. On the other hand, meridional phase was excellent to both sites and vertical wavelength of 25 km was observed practically every month to CR and CA. The zonal phase presented some difficult to get vertical wavelength according to criteria adopted to calculate it. Considering diurnal zonal amplitude, when we compare CR and CA, we could expect a poor agreement of amplitude between them. That is normal if we believe that this is because the geographical location of both sites are completely different in terms of local climate even if they are close to the equator and effect of heat latent release could lead to different response at high altitudes.


Author(s):  
A. Divij Reddy ◽  
A. K. Chaurasia ◽  
P. K. Shukla ◽  
Ram Pal Singh

Presence of hard seed coats and several seed borne pathogens hinder the normal seedling establishment in legumes. Earlier seed enhancement is mainly achieved though synthetics and growth regulators. To evaluate the effect of organics and botanicals on quality parameters of the seed an experiment was conducted in Sam Higginbottom University of Agriculture, Technology and Sciences. Treatments in the experiment comprised of Panchagavya at 3%, 5% and 7% for 12 hrs., Beejamrutha at 5%, 7% and 9% for 12 hrs., Coconut water at 6% and 8% for 12hrs., Moringa leaf extract at 5% and 7% for 12hrs and Sea weed extract at 3% and 5% for 12hrs.Priming with the selected organics and botanicalsis found to enhance the quality parameters compared to untreated control. The treatment Panchagavya at 7% for duration of 12 hours was found to be superior compared to the other treatments in the study.


2010 ◽  
Vol 37 (1) ◽  
pp. 78-82 ◽  
Author(s):  
W. H. Faircloth ◽  
E. P. Prostko

Abstract Recurrent problems with peanut seed germination and stand establishment have raised concerns about the potential effects of herbicides on peanut seed quality. Field trials were conducted in south Georgia in 2005 and 2006 to evaluate the effects of imazapic and 2,4-DB on peanut yield, grade, incidence of tomato spotted wilt virus (TSWV), and seed germination. Imazapic at 71 g ai ha−1, applied at 30 and 40 days after planting (DAP), and 2,4-DB at 270 g ai ha−1, applied at 75 or 90 DAP, had no effect on peanut yield, grade, incidence of TSWV, and seed germination when averaged over two locations (Dawson and Tifton) and three cultivars (Georgia Green, Georgia-01R, and C-99R). Normal cultivar yield variations were observed; however, Georgia-01R had reduced standard (25 C) and cold (15 C) germination when compared to the other cultivars.


1960 ◽  
Vol 40 (3) ◽  
pp. 474-481 ◽  
Author(s):  
T. Lawrence

A study was conducted -with Russian wild ryegrass, Elymus junceus Fisch., to relate seed quality to stage of maturity of the seed at rime of harvest and method of harvesting. Removal of the seed from the seed culms at an immature stage (straight combining), and drying the seed immediately after, had a detrimental effect on the germinability of the seed. This effect decreased as maturity advanced until there was no appreciable germination loss 2 to 3 days before complete maturity. On the other hand, if the seed was left attached to the seed culms until dry and then threshed (swather method) the loss of seed quality attributable to reduced germination was considerably less. However, seed harvested more than 6 days before maturity by both methods had a rather low 100-kernel weight which might he reflected in lower seed yields.


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