Germination response across populations of the stenoendemic chasmophyte Campanula raineri (Campanulaceae)

Abstract For physiologically dormant (PD) species in fire-prone environments, dormancy can be both complex due to the interaction between fire and seasonal cues, and extremely deep due to long intervals between recruitment events. Due to this complexity, there are knowledge gaps particularly surrounding the dormancy depth and cues of long-lived perennial PD species. This can be problematic for both in situ and ex situ species management. We used germination experiments that tested seasonal temperature, smoke, dark and heat for 18 PD shrub species distributed across temperate fire-prone Australia and assessed how germination was correlated with environmental factors associated with their home environments. We found extremely high levels of dormancy, with only eight species germinating above 10% and three species producing no germination at all. Seven of these eight species had quite specific seasonal temperature requirements and/or very strong responses to smoke cues. The maximum germination for each species was positively correlated with the mean temperature of the source population but negatively correlated with rainfall seasonality and driest months. The strong dependence on a smoke cue for some of the study species, along with examples from other studies, provides evidence that an obligate smoke response could be a fire-adapted germination cue. Germination response correlated with rainfall season of the source populations is a pattern which has often been assumed but little comparative data across sites with different rainfall seasonality exists. Further investigation of a broader range of species from different rainfall season environments would help to elucidate this knowledge gap.

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Variation of seed germination response to temperature in tomato landraces: An adaptation strategy to environmental conditions

Scientia Horticulturae ◽

10.1016/j.scienta.2021.109987 ◽

2021 ◽

Vol 281 ◽

pp. 109987

Author(s):

Naeimeh Sousaraei ◽

Benjamin Torabi ◽

Kambiz Mashaiekhi ◽

Elias Soltani ◽

Seyyed Javad Mousavizadeh

Keyword(s):

Seed Germination ◽

Environmental Conditions ◽

Adaptation Strategy ◽

Germination Response ◽

Response To Temperature

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In vitro seed germination response of corn hybrids to osmotic stress conditions

age ◽

10.1002/agg2.20087 ◽

2020 ◽

Vol 3 (1) ◽

Author(s):

Charles Hunt Walne ◽

Annabeth Gaudin ◽

W. Brien Henry ◽

Kambham Raja Reddy

Keyword(s):

Seed Germination ◽

Osmotic Stress ◽

Stress Conditions ◽

Corn Hybrids ◽

Germination Response

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Germination response of four South African medicinal plants to a range of temperatures and treatments

Seed Science and Technology ◽

10.15258/sst.2012.40.1.15 ◽

2012 ◽

Vol 40 (1) ◽

pp. 123-128 ◽

Cited By ~ 3

Author(s):

M. Mofokeng ◽

G. Prinsloo ◽

Q. Kritzinger

Keyword(s):

Medicinal Plants ◽

South African ◽

Germination Response

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Effects of light, temperature and population variability on the germination of seven Spanish pines

Seed Science Research ◽

10.1079/ssr2002116 ◽

2002 ◽

Vol 12 (4) ◽

pp. 261-271 ◽

Cited By ~ 31

Author(s):

A. Escudero ◽

F. Pérez-García ◽

A. L. Luzuriaga

Keyword(s):

Habitat Preferences ◽

Population Variability ◽

Nested Models ◽

Germination Response ◽

Germination Characteristics ◽

Different Populations ◽

Effects Of Temperature ◽

Germination Traits ◽

The Relationship ◽

Pine Species

AbstractMost Pinus species are obligate seeders. Thus, knowledge of germination characteristics can help in the understanding, prediction and manipulation of the regeneration and dynamics of pine forests. Seven pine species with contrasting habitat preferences and different genetic pairwise distances are present in the Iberian Peninsula and the Canary Islands: P. halepensis, P. nigra, P. pinaster, P. pinea, P. sylvestris, P. uncinata and P. canariensis. These seven pine species comprise an exceptional experimental set to test some questions related to germination traits, such as: (1) What are the effects of light and temperature on germination, taking into account interpopulation variability? (2) Is there any association of germination traits with habitat (montane versus lowland) preferences? and (3) What is the relationship between germination traits and the genetic distance between pine species? P. nigra, P. sylvestris and P. uncinata seeds showed faster germination rates. Seeds of P. nigra and P. sylvestris reached high total germination percentages in every temperature and light treatment, suggesting an opportunistic germination strategy. Unlike montane pines, lowland pines did show significant effects of temperature on germination response: final germination was higher between 15°C and 20°C than at warmer and alternating temperatures. Relatively low temperatures associated with the winter rainy season would favour germination of most of these species. Nested models showed that population variability was the main source of variation in germination response. Thus, there is no phylogenetic control of the germination response and, surprisingly, germination traits were not related to habitat preferences. As a consequence, we believe that studies of the germination characteristics of a pine species should consider different populations.

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Seed germination response of a noxious agricultural weed Echium plantagineum to temperature, light, pH, drought stress, salinity, heat and smoke

Crop and Pasture Science ◽

10.1071/cp17308 ◽

2018 ◽

Vol 69 (3) ◽

pp. 326 ◽

Cited By ~ 4

Author(s):

Singarayer Florentine ◽

Sandra Weller ◽

Alannah King ◽

Arunthathy Florentine ◽

Kim Dowling ◽

...

Keyword(s):

Soil Moisture ◽

Drought Stress ◽

Invasive Weed ◽

Germination Response ◽

Elevated Salinity ◽

Wide Range ◽

Agricultural Weed ◽

Soil Seedbank ◽

Response To Temperature ◽

Salinity Management

Echium plantagineum is a significant pasture weed in the Mediterranean climatic zone of several countries, including Australia. This invasive weed, introduced as an ornamental into Australia (where it is known as Paterson’s curse), quickly became established and is now a significant weed of agriculture. Although E. plantagineum is a well-established, highly competitive weed that thrives under disturbance and is tolerant of a wide variety of conditions, including varying soil moisture and drought, and some aspects of its ecology remain unknown. This study investigated germination response to temperature and light, pH, soil moisture, salinity, and pre-germination exposure of seed to heat and smoke. Temperature was found to be more influential on germination than light and the species is tolerant to a wide range of pH. However, available moisture may limit germination, as may elevated salinity. Management of this weed requires approaches that minimise soil seedbank input or prevent germination of soil seedbanks.

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