Environmental Correlates for Seed Desiccation Sensitivity of New Caledonian Plant Species1

AbstractLarge differences in seed desiccation sensitivity have been observed previously among ten coffee species (Coffea arabica, C. brevipes, C. canephora, C. eugenioides, C. humilis, C. liberica, C. pocsii, C. pseudo-zanguebariae, C. sessiliflora and C.stenophylla). Of these species,C. libericaandC. humiliswere the most sensitive to desiccation andC. pseudozanguebariaethe most tolerant. A study was carried out using the same seed lots to investigate if these differences in desiccation tolerance could be correlated with differences in soluble sugar content. Soluble sugars were extracted from dry seeds and analysed using high performance liquid chromatography. The seed monosaccharide (glucose and fructose) content was very low (1.5 to 2 mg g-1dry weight [dw]) in all species studied. The sucrose content ranged from 33 mg g-1dw inC. libericaseeds to 89 mg g-1dw in seeds ofC. pocsii. Raffinose was detected in the seeds of only five species (C.arabica, C.brevipes, C.humilis, C.sessiliflora, C.stenophylla), among which only three species (C.arabica, C.sessilifloraandC.brevipes) also contained stachyose. Both raffinose and stachyose were present in very low quantities (0.3–1.4 mg g-1dw and 0.1–0.7 mg g-1dw, respectively). Verbascose was never detected. No significant relationship was found between seed desiccation sensitivity and: (i) the sugar content; (ii) the presence/absence of oligosaccharides; and (iii) the oligosaccharide:sucrose ratio.

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Seed storage behaviour of 101 woody species from the tropical rainforest of southern China: a test of the seed-coat ratio–seed mass (SCR–SM) model for determination of desiccation sensitivity

Australian Journal of Botany ◽

10.1071/bt14037 ◽

2014 ◽

Vol 62 (4) ◽

pp. 305 ◽

Cited By ~ 6

Author(s):

Qin-ying Lan ◽

Ke Xia ◽

Xiao-feng Wang ◽

Jun-wei Liu ◽

Jin Zhao ◽

...

Keyword(s):

Moisture Content ◽

Seed Coat ◽

Tropical Rainforest ◽

Southern China ◽

Seed Mass ◽

Seed Storage ◽

Woody Species ◽

Seed Moisture Content ◽

Seed Desiccation ◽

Desiccation Sensitivity

The Xishuangbanna tropical rainforest in Yunnan Province is the greatest biodiversity hotspot in China. However, the biodiversity of this region is under threat, making seed conservation through seed and/or germplasm banking particularly urgent and crucial. Seed desiccation sensitivity limits the possibility of seed banking of 47% of tropical rainforest species. Thus, knowing if a species has desiccation-sensitive seeds is an important first step in seed banking; however, often resources are limited, making it difficult to determine storage behaviour for all the species in a region. Prediction of seed sensitivity using the SCR–SM model based on seed-coat ratio (SCR) and seed dry mass (SM) might be an alternative for determining desiccation sensitivity of seeds of each species. Here, seed-desiccation sensitivity of 101 woody species from the Xishuangbanna tropical forest were analysed using this model, and physiological determinations were made for a total of 25 species. Seed storage behaviour for 59 species was used for model validation, and storage behaviour of 88% of these species was successfully predicted. Seed storage behaviour of 83% of the 59 species was successfully predicted using the 1000-seed weigth–moisture content (TSW–MC) criteria, which include seeds with 1000-seed weight >500 g and seed moisture content at shedding of 30 –70%. The two predictive methods were subsequently used to predict seed desiccation sensitivity for another 42 species from Xishuangbanna whose storage behaviour was uncertain. Our results indicated that ~50% of the species in Xishuangbanna are likely to have desiccation-sensitive seeds.

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Ecological significance of seed desiccation sensitivity in Quercus ilex

Annals of Botany ◽

10.1093/aob/mct025 ◽

2013 ◽

Vol 111 (4) ◽

pp. 693-701 ◽

Cited By ~ 23

Author(s):

Thierry Joët ◽

Jean-Marc Ourcival ◽

Stéphane Dussert

Keyword(s):

Quercus Ilex ◽

Ecological Significance ◽

Seed Desiccation ◽

Desiccation Sensitivity

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Predicting the global incidence of seed desiccation sensitivity

Journal of Ecology ◽

10.1111/1365-2745.12725 ◽

2017 ◽

Vol 105 (4) ◽

pp. 1082-1093 ◽

Cited By ~ 47

Author(s):

Sarah V. Wyse ◽

John B. Dickie

Keyword(s):

Seed Desiccation ◽

Desiccation Sensitivity

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Evolutionary ecophysiology of seed desiccation sensitivity

Functional Plant Biology ◽

10.1071/fp18022 ◽

2018 ◽

Vol 45 (11) ◽

pp. 1083 ◽

Cited By ~ 9

Author(s):

Alexandre Marques ◽

Gonda Buijs ◽

Wilco Ligterink ◽

Henk Hilhorst

Keyword(s):

Desiccation Tolerance ◽

Molecular Mechanisms ◽

Genetic Alterations ◽

Tropical Rainforests ◽

Model Species ◽

Seed Desiccation ◽

Desiccation Sensitivity ◽

Selection For ◽

Shed Light

Desiccation sensitive (DS) seeds do not survive dry storage due to their lack of desiccation tolerance. Almost half of the plant species in tropical rainforests produce DS seeds and therefore the desiccation sensitivity of these seeds represents a problem for and long-term biodiversity conservation. This phenomenon raises questions as to how, where and why DS (desiccation sensitive)-seeded species appeared during evolution. These species evolved probably independently from desiccation tolerant (DT) seeded ancestors. They adapted to environments where the conditions are conducive to immediate germination after shedding, e.g. constant and abundant rainy seasons. These very predictable conditions offered a relaxed selection for desiccation tolerance that eventually got lost in DS seeds. These species are highly dependent on their environment to survive and they are seriously threatened by deforestation and climate change. Understanding of the ecology, evolution and molecular mechanisms associated with seed desiccation tolerance can shed light on the resilience of DS-seeded species and guide conservation efforts. In this review, we survey the available literature for ecological and physiological aspects of DS-seeded species and combine it with recent knowledge obtained from DT model species. This enables us to generate hypotheses concerning the evolution of DS-seeded species and their associated genetic alterations.

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Ecological aspects of seed desiccation sensitivity

Journal of Ecology ◽

10.1046/j.1365-2745.2003.00760.x ◽

2003 ◽

Vol 91 (2) ◽

pp. 294-304 ◽

Cited By ~ 191

Author(s):

John C. Tweddle ◽

John B. Dickie ◽

Carol C. Baskin ◽

Jerry M. Baskin

Keyword(s):

Seed Desiccation ◽

Desiccation Sensitivity ◽

Ecological Aspects

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Seed desiccation sensitivity of Quercus fabri and Castanopsis fissa (Fagaceae)

Seed Science and Technology ◽

10.15258/sst.2010.38.1.23 ◽

2010 ◽

Vol 38 (1) ◽

pp. 225-230 ◽

Cited By ~ 4

Author(s):

M.H. Tian ◽

A.J. Tang

Keyword(s):

Seed Desiccation ◽

Desiccation Sensitivity

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Quantitative estimation of seed desiccation sensitivity using a quantal response model: application to nine species of the genus Coffea L.

Seed Science Research ◽

10.1017/s096025859900015x ◽

1999 ◽

Vol 9 (2) ◽

pp. 135-144 ◽

Cited By ~ 31

Author(s):

Stéphane Dussert ◽

Nathalie Chabrillange ◽

Florent Engelmann ◽

Serge Hamon

Keyword(s):

Quantitative Estimation ◽

Continuous Distribution ◽

Seed Viability ◽

Logistic Distribution ◽

Response Model ◽

Quantal Response ◽

Seed Desiccation ◽

Desiccation Sensitivity ◽

Coffee Species ◽

The Continuum

AbstractSeed desiccation sensitivity was studied in nine species of the genus Coffeaby measuring seed viability after equilibration over various saturated salt solutions. A quantal response model based on the logistic distribution was developed in order to describe the typical S-shaped patterns observed. The closeness of fit of the desiccation sensitivity model was shown, and the assumption that seed desiccation sensitivity follows a continuous distribution within species was verified. For each species, the water content at which 50% of initial viability was reached, WC50, and a specific parameter describing the intra-specific variability, β, were calculated using a non-linear regression. A simplified water sorption model was developed which allowed easy calculation of water activity and water potential corresponding to WC50 (aw50 and Ψ50) for relative humidities ranging between 10 and 100%. Distribution of WC50and Ψ50 (or aw50) in the genus Coffea was homogeneous within the following intervals: from 0.05 to 0.38 g H2O.g−1dw for WC50 and from −168 to −11 MPa for Ψ50. Different classifications of the coffee species studied as regards to their desiccation sensitivity were obtained depending on whether WC50 or Ψ50was used for classification. The continuum for desiccation sensitivity observed within the nine species studied confirmed that coffee is an appropriate material for studying desiccation sensitivity.

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Relationship between seed desiccation sensitivity, seed water content at maturity and climatic characteristics of native environments of nineCoffeaL. species

Seed Science Research ◽

10.1017/s0960258500000337 ◽

2000 ◽

Vol 10 (3) ◽

pp. 293-300 ◽

Cited By ~ 34

Author(s):

Stéphane Dussert ◽

Nathalie Chabrillange ◽

Florent Engelmann ◽

François Anthony ◽

Jacques Louarn ◽

...

Keyword(s):

Water Content ◽

Seed Development ◽

Dry Season ◽

Natural Habitats ◽

Seed Moisture Content ◽

Seed Desiccation ◽

Desiccation Sensitivity ◽

Climatic Characteristics ◽

Coffee Species ◽

Seed Water Content

AbstractA broad variability for seed desiccation sensitivity, as quantified by the water content and the water activity at which half of the initial viability is lost, has been previously observed within nine African coffee species. In order to investigate if these different degrees of desiccation sensitivity correspond to an adaptive trait, additional data, such as the duration of seed development and seed water content at maturity, were measured for these species, and the relationships between these parameters and some climatic characteristics of their specific native environments were investigated. Since flowering in all coffee species occurs only a few days after the main rainfall marking the end of the dry season, simulations could be made, based on the continuous sequences of rainfall data compiled in databases of nine climatic stations, chosen for their appropriate location in the collecting areas. The simulations revealed a highly significant correlation between the duration of seed development and that of the wet season. Consequently, mature seeds are shed at the beginning of the following dry season. Moreover, the mean number of dry months that seeds have to withstand after shedding was significantly correlated with the parameters used to quantify seed desiccation sensitivity. By contrast, seed moisture content at maturity was not correlated with the level of seed desiccation tolerance. All these results are discussed on the basis of more detailed descriptions of the natural habitats of the coffee species studied.

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