Germination characteristics of Agriophyllum squarrosum

2004 ◽  
Vol 82 (11) ◽  
pp. 1662-1670 ◽  
Author(s):  
Yuanrun Zheng ◽  
Yong Gao ◽  
Ping An ◽  
Hideyuki Shimizu ◽  
Glyn M Rimmington

Agriophyllum squarrosum (L.) Moq. (Chenopodiaceae), a pioneer species of natural succession in semi-arid regions of China, is widely used for vegetation rehabilitation by air seeding. Experiments were conducted to determine the effects of light intensity and photoperiod, as well as constant and alternating temperatures, on germination to improve the technology of air seeding. Seed of A. squarrosum rarely (<18.5%) germinated at 5/15, 10/20, 15/25, and 20/30 °C (night/day); 39.5% of seeds germinated at 25/35 °C in a 14-h (215 µmol·m–2·s–1) photoperiod. Under dark conditions there was a high final percent seed germination (>90%), except for 71.8% final percent seed germination at 5/15 °C. Constant temperature conditions were associated with lower seed germination (<50%). Less than 13% of seeds germinated at different light intensities (25–400 µmol·m–2·s–1) at 10/20 °C. There was no significant difference in final percent germination when seeds were exposed to 400, 100, or 25 µmol m–2 s–1 for 2 h daily. Final percent germination and germination rate deceased rapidly when the photoperiod was increased under 400 µmol·m–2·s–1. Only 49.2% of seeds germinated after 3 d. Because of the deleterious effect of light on germination, air seeding in late May is recommended.Key words: Agriophyllum squarrosum, air seeding, alternating temperature, constant temperature, light, semi-arid regions.

Author(s):  
Kliff Eldry G. Ibañez ◽  
Larry V. Padilla

Aims: Malayan box turtles’ (Cuoraamboinensis) ecological niche are essential in an ecosystem but are often overlooked. This study investigated the germination of selected seeds that passed through the gut of Malayan box turtles to determine its role in promoting seed dispersal and aiding seed germination. Study Design:Experimental approach. Place and Duration of Study:Pamantasan ng Lungsod ng Maynila (University of the City of Manila) and Dasmarinas, Cavite between June 2016 to March 2017. Methodology: The seeds that passed through the turtle’s gut (Gut Passed Seeds) and seeds that did not pass through its gut (Mechanically Extracted Seeds) underwent comparative germination test. The Germination Rate (GR) and Percent Germination (%GR) of each group were determined in the study.Seed shadowing was also conducted to evaluate the turtle’s seed dispersal capacity (endozoochory). Results: Results showed that after gut passage, seed GR and %GR were enhanced on Lycopersiconesculentum, Carica papaya, Psidiumguajava, and Muntingiacalabura. However, Germination Rate and Percent Germination of Passifloraquadrangularis decreased after gut passage. Statistical analyses revealed that there is a significant difference in the GR and %G of M. calabura and %G of L. esculentum, and P. quadrangularis. Thread trailing method showed that C. amboinensis can disperse seeds at a distance of 24.8 to 52.8 meters. Conclusion: This study demonstrates the important role of C. amboinensis in the ecosystem through its contribution to plant seed germination and dispersal.It showed that Malayan box turtles are not only seed dispersal agents but are also important in the germination of seeds that they have ingested and defecated.


Weed Science ◽  
1986 ◽  
Vol 34 (6) ◽  
pp. 865-870 ◽  
Author(s):  
Susan E. Weaver ◽  
A. Gordon Thomas

Percent germination and germination rates of seeds of atrazine (6-chloro-N-ethyl-N′-(1-methylethyl)-1,3,5-triazine-2,4-diamine)-resistant and -susceptible biotypes of redroot pigweed (Amaranthus retroflexusL. # AMARE) and Powell amaranth (A. powelliiS. Wats. # AMAPO) from southern Ontario were compared in petri dishes using a 100-cell germination plate. The plate provided 100 separately controlled, alternating temperature combinations ranging from 0 to 45 C in increments of 5 C. The experiment was conducted under alternating light and dark conditions for 21 days and under constant dark conditions for 7 days. Initial seed viabilities exceeded 90% for all four biotypes. Under alternating light and darkness, the resistant biotype of Powell amaranth had significantly lower total germination and a slower rate of germination than the susceptible biotype, whereas the biotypes of redroot pigweed did not differ in germination response. Germination rate and total germination were positively correlated for all four biotypes. In constant darkness, the atrazineresistant biotypes of both species had significantly lower germination percentages compared to the susceptible biotypes. In general, percent germination of Powell amaranth was greater than that of redroot pigweed for day and night temperatures <25 C, whereas redroot pigweed had greater germination at higher temperatures. Greater seed dormancy of the resistant biotypes under some light and temperature combinations may have implications for the persistence of resistant populations in the field.


2010 ◽  
Vol 2 (2) ◽  
pp. 41-45 ◽  
Author(s):  
Vinay Madhukar RAOLE ◽  
Aruna Girish JOSHI ◽  
Sandhya Kiran GARGE ◽  
Rinku Jitendrakumar DESAI

The district of Kachchh contains many culturally important plants. However, their conservation status is little known due to direct and indirect human activities. This study was undertaken with the aim of contributing to the conservation of the native species of these semi-arid regions through germination trials under laboratory conditions. Mature fruits of ten selected species were collected randomly from the known habitats to obtain viable seeds. These seeds were pre-treated with growth regulators singly or in combination after acid scarification or without scarification. Seeds were found to be dormant due to presence of thick seed coat or due to low level of endogenous hormonal level. Most of these seeds required different storage period to mature. Only seeds of Capparis cartilaginea germinated without treatment while the other species required treatments. Addition of growth regulators has enhanced seed germination in few taxa singly and in some plant cases in combination.


2014 ◽  
Vol 614 ◽  
pp. 653-657 ◽  
Author(s):  
Xiao Xue Shen ◽  
Min Wei Chai ◽  
Rui Li Li ◽  
Guo Yu Qiu

A study quantifying the role of the interactive effects of salt and drought stresses, generally co-occurred in deserts, on seed germination in Ammopiptanthus mongolicus was conducted in a constant temperature incubator. The experiment consisted of seven levels of salinity stress (0, 0.3, 0.6, 0.9, 1.2, 1.5 and 1.8% NaCl) as well as six drought stress levels (0, -0.2, -0.4, -0.8, -1.6 and-2.0 MPa PEG). Accordant to our expectations, the interactive effects of salinity and drought stresses were additive on seed germination percentages, germination rate, and germination energy; significant decreases were seen in all of them in response to increases in salt and/or drought stresses. Furthermore, regression coefficients of salinity (β1) were higher than drought (β2), indicating that salinity was the first factor, and drought was secondary for salt and drought mixed stresses.


HortScience ◽  
2019 ◽  
Vol 54 (11) ◽  
pp. 1902-1906 ◽  
Author(s):  
Tyler Hoskins ◽  
Ryan N. Contreras

Sweetbox (Sarcococca confusa) is an evergreen shrub valued for attractive foliage, winter fragrance, black fruit, as well as shade and drought tolerance. The high degree of apomixis in Sarcococca limits the effectiveness of conventional breeding practices. However, mutation breeding may be a valuable tool to induce variation in seedling crops. As such, a study was conducted to expose seeds of S. confusa to ethyl methanesulfonate (EMS) at varying concentrations and exposure durations, and to evaluate the effects on seed germination, growth, and relative frequency of polyembryony. In 2010, seeds of S. confusa were treated with 0%, 0.2%, 0.4%, 0.8%, and 1.2% EMS for 24 and 48 hours. Seeds were sown and the relative germination and occurrence of polyembryony were recorded. Seedlings were later evaluated for size and phenotypic variation in the subsequent growing seasons. Percent germination was found to decrease with increasing EMS rates in the 24- and 48-hour treatments. The occurrence of polyembryony also decreased with increasing EMS rates in the 24-hour treatment but was observed to be greatest at 0.2% EMS. No significant differences in plant size index (SI) were found after four growing seasons. When mature, seeds were collected from any plants that bore fruit in each treatment and were then sown. The percentage of plants that bore fruit in each treatment decreased with increasing EMS rates, although the germination rate of these seeds did not differ. A chlorophyll mutant and several dwarf forms were identified in this population as well. They have been propagated asexually for future evaluation as new cultivars. This study demonstrates the utility of chemical mutagenesis to induce phenotypic variation in S. confusa while reducing the rate of polyembryony.


2017 ◽  
Vol 3 (4) ◽  
pp. 233
Author(s):  
Sri Ulie Rahmawati ◽  
Arief Noor Rachmadiyanto

<p class="Els-body-text"><em>Markhamia stipulata </em>(Wall.) Seem. (Bignoniaceae) is one of collections in Bogor Botanical Garden that potential as a medicine. Information about germination of these species were not known yet. This research was aimed to examine the effect of light color on germination process of <em>Markhamia stipulata</em> (Wall.) Seem. The research method used a Randomized Complete Block Design (RCBD) that consist of three treatments (red light, far red light, dark) and one control (open air) with four replications for each group. Each group consist of 10 seeds. Precentage of seed germination; seedling height; cotyledon width; length, width and number of leaves were measured. The result showed that seed germination start at third day after sowing.  Germination rate and germination rate coefficcient showed there is no significant difference between all treatments even though far red light showed highest number (100 %; 0.755).  However, light color influence on seedling growth. Far red light showed affect on internodes distance. Dark light showed affect on leaves and cotyledon size. Red light and control showed similarity.</p><p> </p><div><p class="Els-keywords"><strong>Keywords:</strong> dark; far red light<em>, </em><em>Markhamia stipulata</em> (Wall.) Seem; red light; seed germination</p></div>


2005 ◽  
Vol 83 (8) ◽  
pp. 1021-1028 ◽  
Author(s):  
Yuanrun Zheng ◽  
Glyn M Rimmington ◽  
Yong Gao ◽  
Lianhe Jiang ◽  
Xuerong Xing ◽  
...  

Artemisia ordosica Krasch. (Asteraceae) is the dominant psammophytic shrub species on the Ordos Plateau of northern China and is used for revegetation of semi-arid areas. Experiments were conducted to determine the effects of light intensity, constant temperature, alternating temperatures, and water potential on germination to determine why air-dispersed achenes fail to germinate well in the field. Achenes germinated within a wide alternating temperature window, except under the 5:15 °C (night:day) temperature regime in darkness. Final percent germination (FPG) was higher in darkness than in light at alternating temperature regimes, except under the 20:30 °C (night:day) temperature regime. Achenes subjected to a range of constant temperatures in the dark had high FPG over 76.8% except at 30 °C (8%). Photosynthetic photon flux densities (PPFD) of 100 and 400 µmol·m–2·s–1 significantly lowered FPG under a 10:20 °C (night:day) regime, while at 0–25 µmol·m–2·s–1 PPFD, the FPG was over 92%. Few achenes germinated at –1.4 MPa. The most suitable temperature for germination of achenes placed under water stress was 20 °C. The best timing for air dispersal is mid-May, so seeds would become covered with sand at a time when temperature and soil moisture conditions were optimal for germination.Key words: air dispersal, Artemisia ordosica, hydrothermal time, psammophytes, semi-arid regions, temperature.


HortScience ◽  
2011 ◽  
Vol 46 (4) ◽  
pp. 651-654 ◽  
Author(s):  
Qi Zhang ◽  
Sheng Wang ◽  
Kevin Rue

Salinity tolerance of 12 turfgrasses in four groups, creeping bentgrass (Agrostis stolonifera L.), fescues (Festuca spp.), kentucky bluegrass (Poa pratesis L.), and alkaligrass [Puccinellia distans (Jacq.) Parl.], was evaluated using three germination methods. Seeds were germinated on 1% agar medium, on germination paper, or in a hydroponic system under salinity levels of 0, 5, 10, 15, or 20 g·L−1 NaCl. Germination rate and seedling growth of each grass were determined. Salinity reduced the final germination rate (FGR), daily germination rate (DGR), and seedling leaf area (LA) in all tests. On agar medium, no significant difference in salinity tolerance was observed among the four turf groups; however, ‘Turf Blue’ kentucky bluegrass with a corn starch-based coating (coated ‘Turf Blue’) showed a significant higher salinity tolerance than the uncoated one. Using germination paper, creeping bentgrass required the highest salinity level to cause 50% reduction in FGR followed by alkaligrass, fescues, and kentucky bluegrass. Kentucky bluegrass required the lowest salinity level (9.5 g·L−1) to reduce DGR by 50%. With the hydroponic system, alkaligrass required a salinity level of 26.3 g·L−1 to reduce FGR by 50%, the highest among the four groups. Alkaligrass showed again the highest salinity tolerance with an average of 12.7 g·L−1 needed to reduce LA by 50%. Among the grasses, coated ‘Turf Blue’ kentucky bluegrass, ‘Declaration’ creeping bentgrass, and ‘Fults’ alkaligrass showed the highest salinity tolerance when evaluated on agar medium, on germination paper, or in the hydroponic system, respectively. The present study determined the salinity tolerance of 12 turfgrasses at seed germination and early seedling growth stages and showed that the germination method was a factor affecting the evaluation result and it should be considered in a seed germination test of turfgrass for salinity tolerance.


HortScience ◽  
2006 ◽  
Vol 41 (5) ◽  
pp. 1330-1331 ◽  
Author(s):  
J.S. Shin ◽  
P. Raymer ◽  
W. Kim

Seashore paspalum (Paspalum vaginatum O. Swartz) is a perennial warm-season grass that is rapidly gaining popularity for use on golf courses and athletic fields. The first seeded cultivar of seashore paspalum was recently developed. Seed from the pilot production of this cultivar harvested in Oregon during 2002 by Turf-Seeds, Inc. demonstrated a high level of apparent seed dormancy with a tetrazolium test of 91% but a germination rate of less than 5% at room temperature. This seed was used in laboratory experiments to determine the effect of a number of environmental factors on germination response in this new turf species. Treatment factors are germination media, constant and alternating (night/day) temperatures, and light. A strong and significant effect of temperature on germination was observed. Total germination was increased at higher temperatures. At the same daytime temperature, seed germination under alternating temperature was better than germination at constant temperature. The effect of light on germination was significant at 20, 25, 30, 20/35 °C in water and at 25/35 °C in 0.2% KNO3 germination media. However, the effect of light on germination in KNO3 media was not significant at 35 °C constant and 20/30 °C alternating temperatures. Alternating temperature used in conjunction with KNO3 media reduced the requirement for light. The use of 0.2% KNO3 rather than water as the germination media increased germination in most temperature and light treatments. Based on our results, maximum germination percentage was obtained when seed was germinated at 35 °C constant or 20/35 °C alternating temperature. However, when we consider field application, 25/35 °C with light is more realistic condition in field. Therefore, recommended seed germination test condition is at 25/35 °C with KNO3 treatment.


Author(s):  
T. Chitdeshwari ◽  
P.M. Brindhavani

Background: Soil calcareousness is the major problem in arid and semi arid regions globally since lime induced chlorosis lead to the deficiency of many essential plant nutrients which in turn resulted in reduced growth and yield loss of many crops. To explore the effects of various concentrations of calcium carbonate (CaCO3) on seed germination and seedling growth of groundnut genotypes and to identify CaCO3 stress tolerant and sensitive groundnut genotypes. Methods: The seed germination and seedling growth of ten groundnut genotypes (CO 6, CO 7, TMV 2, TMV 10, TMV 13, TMV 14, VRI 7, VRI 8, ALR 2 and BSR 2) was investigated with CaCO3 concentrations ranging from 1 to 100 mM L-1 for a period of 14 days. Result: The genotypes VRI 8 and TMV 10 showed higher seed germination and seedling growth even at higher CaCO3 concentration (upto 20 mM L-1) and considered as tolerant genotypes. Whereas TMV 2 and VRI 7 exhibited drastic reduction even at 1 mM L-1 and confirms their susceptibility to CaCO3 stress. Higher concentrations of CaCO3 in the growing medium greatly decreased the germination rate, germination index and vitality index but the impact differs with potentials of genotypes studied.


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