scholarly journals Temperature effects on Cuscuta campestris Yunk. seed germination

2013 ◽  
Vol 28 (3) ◽  
pp. 187-193 ◽  
Author(s):  
Marija Saric-Krsmanovic ◽  
Dragana Bozic ◽  
Danijela Pavlovic ◽  
Ljiljana Radivojevic ◽  
Sava Vrbnicanin
Keyword(s):  
Seed Germination ◽  
Weed Control ◽  
Sulphuric Acid ◽  
Temperature Effects ◽  
Room Temperature ◽  
Biological Characteristics ◽  
Cuscuta Campestris ◽  
Different Temperatures ◽  
C 30 ◽  
Germinated Seeds

Studies of biological characteristics of seeds and conditions for their germination have a major importance for planning and executing rational measures of weed control. The aim of this study was to investigate the effect of different temperatures on germination of C. campestris seeds. Three treatments (T1- storage at room temperature; T2 - exposure to 4?C for 30 days; T3 - scarification by concentrated sulphuric acid) differing in manipulation with seeds before germination were tested at different temperatures (5?C, 10?C, 15?C, 20?C, 25?C, 30?C, 35?C, 40?C, 45?C). Germinated seeds were counted daily for ten days and the length of seedlings was measured on the last day. The results showed that differences in germination of C. campestris seeds were very prominent between temperatures, as well as between treatments T1, T2 and T3. Seeds failed to germinate at 5?C and 45?C in all treatments (T1, T2, T3). Germination ranged from 6.25 at 10?C to 96.88%, the highest percentage, achieved at 30?C.

scholarly journals Impact of storage conditions on seed germination and seedling growth of wild oat (Avena fatua L.) at different temperatures

2015 ◽  
Vol 30 (4) ◽  
pp. 243-248
Author(s):  
Marija Saric-Krsmanovic ◽  
Gajic Umiljendic ◽  
Ljiljana Santric ◽  
Ljiljana Radivojevic
Keyword(s):  
Seed Germination ◽  
Germination Rate ◽  
Seed Storage ◽  
Storage Conditions ◽  
Avena Fatua ◽  
Shoot Length ◽  
Wild Oat ◽  
Different Temperatures ◽  
C 30 ◽  
Germinated Seeds

The influence of seed storage conditions and different temperatures (5?C, 10?C, 15?C, 20?C, 25?C, 30?C and 26?C/21?C) during germination and seedling development on seed germination, shoot length and germination rate of wild oat (Avena fatua L.) was examined. Germinated seeds were counted daily over a period of ten days and shoot length was measured on the last day, while germination rates were calculated from those measurements. The results showed that seed storage under controlled conditions (T1: temperature 24?1?C, humidity 40-50%; T2: temperature 26?1?C, humidity 70-80% and T3: temperature 4?C) for periods of 3 (t1) and 12 (t2) months had a significant influence on germination of wild oat seeds. The percentage of germinated seeds under all examined temperatures was higher when they were stored for 12 months under controlled temperature and humidity. The results also showed that temperature had a significant effect on the percentage of germination and germination rate of A. fatua seeds. The highest total germination occurred at 15?C temperature (T1: t1 - 41.25%, t2 - 44.37%; T2: t1 - 28.13%, t2 - 34.37%; T3: t1 - 10.63%, t2 - 12.50%). Germination percentage under an alternating day /night photoperiod at 26?C/21?C temperature was higher in all treatment variants (T1: t1 - 8.13%, t2 - 10.00%; T2: t1 - 11.87%, t2 - 13.13%; T3: t1 - 2.42%, t2 - 2.70%) than germination in the dark at 25?C, 30?C and 5?C.

scholarly journals The Impacts of Temperature, Soil Type and Soil Herbicides on Seed Germination and Early Establishment of Common Milkweed (Asclepias syriaca

2016 ◽  
Vol 44 (1) ◽  
pp. 291-295 ◽  
Author(s):  
Ljiljana RADIVOJEVIC ◽  
Marija SARIC-KRSMANOVIC ◽  
Jelena GAJIC UMILJENDIC ◽  
Dragana BOZIC ◽  
Ljiljana SANTRIC
Keyword(s):  
Seed Germination ◽  
Germination Rate ◽  
Germination Percentage ◽  
Soil Types ◽  
Asclepias Syriaca ◽  
Seedling Length ◽  
Different Temperatures ◽  
C 30 ◽  
Early Establishment ◽  
Germinated Seeds

The effects of different temperatures (20 °C, 25 °C, 30 °C, 35 °C and photoperiod 26 °C/21 °C), types of soil (sand and loam) and soil herbicides (oxyfluorfen, terbuthylazine and mesotrione) on seed germination percentage, germination rate, as well as seedling length and weight of common milkweed (Asclepias syriaca L.) were examined. Over a period of ten days, germinated seeds were counted daily, and seedling length and weight were measured on the final day and germination rate calculated. The results indicated that temperature was the factor that significantly affected the percentage of germinated seeds of common milkweed, seedling length and germination rate, while it had less influence on seedling weight. The results showed that the alternating day/night temperature of 26 °C/21 °C also had a significant impact as the percentage of germinated seeds was the highest at that temperature on both soil types (sand: 71.3%; loam: 61.3%). Data regarding the herbicides tested (oxyfluorfen, terbuthylazine and mesotrione) showed decreasing germination percentage and seedling length with increasing herbicide concentrations on both soil types. Their effect was weakest on seedling weight. Tested herbicides are usable in control of common milkweed at the stages of germination and early establishment.

Influence of Heat on Seed Germination of Cistus Laurifolius and Cistus Ladanifer

1992 ◽  
Vol 2 (1) ◽  
pp. 15 ◽  
Author(s):  
L Valbuena ◽  
R Tarrega ◽  
E Luis
Keyword(s):  
Seed Germination ◽  
High Temperatures ◽  
Exposure Time ◽  
Germination Rate ◽  
Heat Exposure ◽  
Cistus Ladanifer ◽  
Different Temperatures ◽  
Petri Dishes ◽  
Germinated Seeds

The influence of high temperatures on germination of Cistus laurifolius and Cistus ladanifer seeds was analyzed. Seeds were subjected to different temperatures for different times, afterwards they were sowed in plastic petri dishes and monitored for germinated seeds over two months.The germination rate observed in Cistus ldanifer was greater than in Cistus laurifolius. In both species, heat increased germination percentages. For Cistus laurifolius higher temperatures or longer exposure times were needed. Germination percentages of Cistus ladanifer were lower when heat exposure time was 15 minutes.It must be emphasized that germination occurred when seeds were not treated, while seeds exposed to 150�C for 5 minutes or more did not germinate.

scholarly journals Low Temperature and Resin Effects on the Mode I Interlaminar Fracture Toughness in Aeronautical Quality Polymer Composites

Proceedings ◽  
2018 ◽  
Vol 2 (23) ◽  
pp. 1478 ◽  
Author(s):  
Patricia Coronado ◽  
Pedro Camanho ◽  
Antonio Argüelles ◽  
Jaime Viña ◽  
Sara Sánchez
Keyword(s):  
Fracture Behavior ◽  
Room Temperature ◽  
Double Cantilever Beam ◽  
Mode I ◽  
Interlaminar Fracture Toughness ◽  
Gompertz Function ◽  
Static Tests ◽  
Composites Materials ◽  
Different Temperatures ◽  
C 30

In the present research the fracture behavior in mode I under static loading of two aircraft quality composites materials has been analyzed at different test temperatures. The composites under study are made of the same unidirectional AS4 carbon fiber reinforcement and had different matrix of epoxy resin, one made of epoxy type 3501-6, and the other with epoxy type 8552 (modified to increase its toughness). Double cantilever beam (DCB) specimens were tested for different temperatures: 20 °C (room temperature), 0 °C, −30 °C and −60 °C, in order to simulate flight conditions. The results obtained from the static tests were analyzed using the Gompertz function.

scholarly journals Seed germination in Cerrado species

2008 ◽  
Vol 20 (3) ◽  
pp. 167-181 ◽  
Author(s):  
Lilian B. P. Zaidan ◽  
Rosana C. Carreira
Keyword(s):  
Seed Germination ◽  
Sulphuric Acid ◽  
Tree Species ◽  
Light Sensitivity ◽  
Dormancy Breaking ◽  
Shrub Species ◽  
Different Temperatures ◽  
Light Effects ◽  
And Storage ◽  
Herb Species

The aim of this review is to comment on the available data about germination of seeds from herb, shrub and tree species of the Cerrado after the publication of the review written by Felippe and Silva in 1984. Studies on seed germination of herbaceous species focused mainly on the responses of seeds to light, different ranges of temperature and storage in the soil. The majority of seeds from herb species germinate between 20°C and 30°C, and are photoblastic. Alternate temperatures favored germination in some seeds, but changed light sensitivity of the achenes of Bidens gardneri. Seeds of most of the shrub species of Melastomataceae are positive photoblastic; among the Velloziaceae, germination in the dark was observed in some species. Other shrub species show dormancy caused by impermeability of the seed tegument, as described for seeds of some species of Bauhinia. Their dormancy is broken by chemical scarification using sulphuric acid. Seeds of Heteropterys pteropetala are sensitive to very high temperatures, similar to those registered during burnings. Some species were considered to have allelopathic effects and could inhibit the germination of seeds of other species and the establishment of plantlets. Seeds of most tree species do not require light to germinate and the focus of the studies were on methods of dormancy breaking. Sulphuric acid and incisions in the tegument proved to be the most efficient methods to break dormancy. In general, the studies are limited to three major aspects: responses to light, effects of different temperatures and dormancy breaking. More studies are necessary to understand the physiological and biochemical aspects of reserve compounds and their mobilization during germination, as well as the effects of fire in these seeds.

scholarly journals Study of storage on seed germination of Chresta sphaerocephala DC. – Asteraceae

2021 ◽  
Vol 10 (9) ◽  
pp. e50110917893
Author(s):  
Amanda Domingas Ediodato de Sousa ◽  
Luciana Botezelli ◽  
Patrícia Neves Mendes
Keyword(s):  
Seed Germination ◽  
Storage Temperature ◽  
Morphological Difference ◽  
Seed Storage ◽  
Seed Vigor ◽  
Significance Level ◽  
Different Temperatures ◽  
And Storage ◽  
Storage Temperatures ◽  
Germinated Seeds

High-altitude fields have been subjected to an intense anthropization process. Due to this, studies on germination, seed storage and propagation of species that compose this plant formation become fundamental. Among such species is the Chresta sphaerocephala DC., Asteraceae. The purpose of this work was to study different temperatures for germination and storage of this species. Four germination temperatures (15°C, 20°C, 25°C and 30°C) and two storage temperatures (-5°C and +5°C) were tested. In order to assess seed vigor, the germination speed index (GSI) and average seed germination time were calculated. ANOVA and Tukey's test were performed at a 5% significance level. In addition, a morphological difference was observed in the analyzed Chresta sphaerocephala seeds, with these being classified as C1 (small seeds), C2 (long thin seeds), C3 (thicker seeds) and C4 (dark colored seeds). As for the storage temperature, 5°C was shown to be the best. When correlated with the germination temperature, 20°C resulted in a statistically higher number of germinated seeds.

EFFECTS OF STORAGE CONDITIONS AND PRESENCE OF FRUITING BRACTS ON THE GERMINATION OF ATRIPLEX HALIMUS AND SALSOLA VERMICULATA

1997 ◽  
Vol 33 (2) ◽  
pp. 149-155 ◽  
Author(s):  
A. E. OSMAN ◽  
F. GHASSALI
Keyword(s):  
Seed Germination ◽  
Cold Storage ◽  
North Africa ◽  
Room Temperature ◽  
Storage Temperature ◽  
Seed Storage ◽  
Storage Conditions ◽  
Shrub Species ◽  
Atriplex Halimus ◽  
Different Temperatures

Two shrub species, Atriplex halimus L. and Salsola vermiculata L., are considered useful for rehabilitation of degraded rangelands in west Asia and north Africa. They can be established from direct seeding and are capable of self-sowing. In this study, seed storage at different temperatures and the influence of fruiting bracts on seed germination were examined for the two species during two seasons. Fruits (utricles) were stored at 20–22°C (room temperature), 0°C or −22°C. Germination tests were carried out after 33, 56, 90, 152, 272 and 397 d in storage in the first season and after 44, 76, 104, 170, 288 and 412 d in the second season. Seeds were germinated in their fruiting bracts or after bract removal. Bract removal significantly improved seed germination of both shrubs regardless of storage temperature. For S. vermiculata the increase in germination was in the range of 1.3- to 14.7-fold compared with values for the intact fruit in Season 1 and 0.5 to 3.8 in Season 2. Similarly the ranges for A. halimus were 0.5- to 4.2-fold and 0.7- to 5.3-fold in the two seasons respectively. The effect of cold storage was greater on Salsola than on Atriplex. The reduction of the storage temperature from 21°C to 0°C and −22°C increased the longevity of S. vermiculata seeds by 2.8–46.6 times in Season 1 and by 2.9–2.6 times in Season 2. There was little or no effect on the longevity of A. halimus. A leachate prepared by soaking fruiting bracts from S. vermiculata significantly depressed germination (p < 0.01), the effect being greater on Salsola seeds (20% reduction) than on Atriplex seeds (8% reduction). A leachate from A. halimus produced a slight but non-significant reduction in germination.

scholarly journals SEED GERMINATION AND SEEDLING ESTABLISHMENT OF CHERIMOYA (ANNONA CHERIMOLA MILL.) AT DIFFERENT TEMPERATURES

2020 ◽  
Vol 53 (2) ◽  
pp. 185-194
Author(s):  
A. KHELOUFI ◽  
L. M. MANSOURI ◽  
H. KHETTACHE
Keyword(s):  
Seed Germination ◽  
Room Temperature ◽  
Germination Percentage ◽  
Annona Cherimola ◽  
Seedling Length ◽  
Different Temperatures ◽  
External Conditions ◽  
Mean Germination Time ◽  
Coefficient Of Velocity ◽  
Kinetics Of

Cherimoya (Annona cherimola Mill.) has an exceptional flavor and aroma, which makes it a fruit with great potential. However, little is known about its propagation by seeds. According to the scientific literature, the germination of cherimoya seeds is affected much more by external conditions than by internal conditions. Germination of cherimoya variety ‘Concha Lisa’ were tested for germination at constant temperatures of 25, 30, 40°C, and at room temperature, varying from 20-25°C, coupled with total darkness. Seeds were sown in Petri dishes (0.8% agar water), for 25 days of incubation. The kinetics of germination was determined according to five closely related parameters, viz. final germination percentage (FGP), mean germination time (MGT), coefficient of velocity of germination (CVG), time to 50% germination (T50) and seedling length (SL). The temperature of 30°C was found optimally suitable with 70.8% FGP, 17.5 days MGT and 3.91 cm SL, while the room temperature of 20-25°C slightly improved germination with only 25% FGP. Furthermore, significant decrease in FGP and SL was observed at 25°C and 40°C of temperature in comparison to 30°C. The analysis also revealed that cherimoya seed germination, day 10-15 after seed sowing is suitable for final counts. An overview on the emergence of cherimoya seedlings, during a 12-week period in pots is presented.

scholarly journals Seed germination in Solidago ×niederederi (Asteraceae) and its parental species after two different fruit storage periods

2017 ◽  
Vol 48 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Artur Pliszko ◽  
Kinga Kostrakiewicz-Gierałt
Keyword(s):  
Seed Germination ◽  
Room Temperature ◽  
Parental Species ◽  
Negative Impact ◽  
Storage Period ◽  
Fruit Storage ◽  
Temperature Conditions ◽  
Fruit Samples ◽  
Germinated Seeds ◽  
Long Storage

Abstract In this paper, we present preliminary results from the study on the effect of fruit storage period on seed germination in Solidago ×niederederi and its parental species (S. canadensis and S. virgaurea). We aimed to test the hypothesis that a long fruit storage period (i) reduces the final percentage and speed of seed germination, as well as (ii) increases the number of dead seeds among non-germinated ones. We used fruit samples collected in Kraków, southern Poland, in 2013 and 2016, designating two different fruit storage periods of 3.5 years and 0.5 years, under dry, room temperature conditions. Seeds of all the observed species presented remarkably higher final percentage of germination after the short storage period than after the long one. The seeds subjected to the short fruit storage period achieved significantly higher values of Timson’s index and coefficient of velocity, as well as significantly lower values of the mean germination time than samples subjected to the long fruit storage period. After the long storage period, a significantly higher number of dead seeds among non-germinated seeds was found in S. ×niederederi and S. virgaurea. The performed studies showing that the long fruit storage period led to low contribution of germinated seeds in S. ×niederederi and its parental species suggested that the longtime seed desiccation had a negative impact on final germination. Considering that the hybrid can be potentially cultivated for scientific, medicinal or ornamental purposes, the suggested fruit storage period, under dry, room temperature conditions, should be shorter than three years. However, we realize that the response to long storage may vary in different populations and, therefore, further investigations are needed.

scholarly journals Effect of Elevated Temperatures on Fiber Reinforced Self Compacting Concrete

2019 ◽  
Vol 8 (3) ◽  
pp. 7775-7778
Keyword(s):  
Compressive Strength ◽  
Temperature Effects ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Steel Fibers ◽  
Muffle Furnace ◽  
Self Compacting Concrete ◽  
Retention Period ◽  
Steel Fibres ◽  
Different Temperatures

The present investigation is mainly focused on study the temperature effects on SCC reinforced with steel fibers on M40 grade of concrete. The main objective of the investigation is inspired from the real world - to know the strength of a concrete after subjected to an elevated temperature. Steel fibres with an aspect ratio of 40varied at a fibre dosage of 0, 1, and 1.5%by the weight of the cement used in this investigation. In this study concrete is exposed to five different residual conditions. In addition to the room temperature there are four different temperatures of 100˚c, 300˚c, 500˚c and 800˚c are considered at a retention period of 1, 2, 3 and 4 hours in muffle furnace. Compressive strength conducted after 28 days of curing. From the experimental results it is observed that SCC with steel fibres reduced the workability on the contrary there is increase in compressive strength observed with the addition of fibres. It is also observed that SCC with steel fibres has shown the better performance compared to control mix at elevated temperatures. This is mainly due to fibres are participated in delaying the cracks.

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