A blueprint of seed desiccation sensitivity in the genome of Castanospermum australe

SummaryMost angiosperms produce seeds that are desiccated on dispersal with the ability to retain viability in storage facilities for prolonged periods. However, some species produce desiccation sensitive seeds which rapidly lose viability in storage, precluding ex situ conservation. Current consensus is that desiccation sensitive seeds either lack or do not express mechanisms necessary for the acquisition of desiccation tolerance.We sequenced the genome of Castanospermum australe, a legume species producing desiccation sensitive seeds, and characterized its seed developmental physiology and - transcriptomes.C. australe has a low rate of evolution, likely due to its perennial life-cycle and long generation times. The genome is syntenic with itself, with several orthologs of genes from desiccation tolerant legume seeds, from gamma whole-genome duplication events being retained. Changes in gene expression during development of C. australe seeds, as compared to desiccation tolerant Medicago truncatula seeds, suggest they remain metabolically active, prepared for immediate germination.Our data indicates that the phenotype of C. australe seeds arose through few changes in specific signalling pathways, precluding or bypassing activation of mechanisms necessary for acquisition of desiccation tolerance. Such changes have been perpetuated as the habitat in which dispersal occurs is favourable for prompt germination.

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Seed desiccation tolerance and germination of four Puya (Bromeliaceae) high-andean tropical species from Colombia

Caldasia ◽

10.15446/caldasia.v40n1.67740 ◽

2018 ◽

Vol 40 (1) ◽

pp. 177-187

Author(s):

Manuela Calderón-Hernández ◽

Laura Victoria Pérez-Martínez

Keyword(s):

Desiccation Tolerance ◽

Ex Situ ◽

Tropical Species ◽

Seed Desiccation

La conservación ex situ de semillas es una de las formas más efectivas de preservación de la biodiversidad y especialmente de la diversidad genética. En el marco del cambio climático su aplicación es una estrategia importante que se debe fortalecer e integrar con la conservación in situ. El objetivo del presente trabajo fue estudiar la tolerancia a la desecación y la germinación de cuatro especies del género Puya y proporcionar herramientas para su conservación ex situ. Estas especies están distribuidas en el páramo, un ecosistema amenazado a pesar de su valor como reservorio y proveedor de agua para la población urbana. En las semillas se realizó la toma de medidas morfológicas y del contenido de humedad (CH), se realizaron ensayos de germinación en tres contenidos de humedad (semillas frescas, 10–12 % y 3–5 %) y se evaluó el porcentaje de germinación y tiempo medio de germinación. Se registró una germinación superior al 80 % en las cuatro especies y no se encontraron diferencias significativas al disminuir el CH. El tiempo medio de germinación no varió entre especies y la viabilidad fue alta comparada con otras especies de páramo. Los resultados indican que son semillas ortodoxas y las variables morfológicas apoyan esta tendencia. Por tanto, este género presenta un gran potencial para ser conservado en bancos de germoplasma lo que contribuye a la conservación de su diversidad, con las cuales se pueden implementar protocolos de germinación para la propagación y reintroducción en programas de restauración.

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Seed desiccation tolerance and dormancy of three endangered New Zealand species: Carmichaelia williamsii, Clianthus puniceus and Hibiscus diversifolius

NZGA: Research and Practice Series ◽

10.33584/rps.14.2008.3185 ◽

2010 ◽

Vol 14 ◽

pp. 13-21

Author(s):

M.J. Park ◽

C.R. Mcgill ◽

W.M. Williams ◽

B.R. Mackay

Keyword(s):

New Zealand ◽

Threatened Species ◽

Desiccation Tolerance ◽

In Situ Conservation ◽

Seed Storage ◽

Storage Conditions ◽

Ex Situ ◽

Dormancy Breaking ◽

Moisture Contents ◽

Seed Desiccation

At least one third of New Zealand's indigenous plant species are threatened with extinction and strategies for conserving endangered flora are urgently required. One strategy is to use ex situ seed storage as a complement to in situ conservation. Successful ex situ storage of seed requires knowledge of the seed storage behaviour, optimal storage conditions and germination requirements of the species being stored. For many threatened species, however, this information is either incomplete or unavailable. In this study, preliminary experiments were conducted with three threatened species, Carmichaelia williamsii, Clianthus puniceus and Hibiscus diversifolius, to determine their desiccation tolerance and dormancy status. Seeds were tested for germination following desiccation and dormancy-breaking treatment. Seeds of all three species could be dried to moisture contents of 2.9-3.7% without losing viability. All three species became predominantly hardseeded at approximately 10% moisture content. However, C. puniceus became permeable to water again at moisture contents below 6%. In all species, manual scarification of seeds improved germination to 96-100% compared with 5-20% in untreated seeds. Dormancy in these species is a function of the seed coat preventing water uptake by the dry seed. While seeds of these species are most likely desiccation tolerant and thus can potentially be stored for long periods under conventional conditions, the loss of dormancy of C. puniceus at very low moisture contents is of concern. More work is needed to confirm the long-term storage behaviour of these species. Keywords: ex situ conservation, seed storage behaviour, New Zealand flora

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Peptide-Bound Methionine Sulfoxide (MetO) Levels and MsrB2 Abundance Are Differentially Regulated during the Desiccation Phase in Contrasted Acer Seeds

Antioxidants ◽

10.3390/antiox9050391 ◽

2020 ◽

Vol 9 (5) ◽

pp. 391 ◽

Cited By ~ 3

Author(s):

Natalia Wojciechowska ◽

Shirin Alipour ◽

Ewelina Stolarska ◽

Karolina Bilska ◽

Pascal Rey ◽

...

Keyword(s):

Desiccation Tolerance ◽

Methionine Sulfoxide ◽

Redox Status ◽

Embryonic Axes ◽

Seed Desiccation ◽

Methionine Sulfoxide Reductases ◽

Norway Maple ◽

Orthodox Seeds ◽

Oxidation Of Methionine ◽

Reduced Forms

Norway maple and sycamore produce desiccation-tolerant (orthodox) and desiccation-sensitive (recalcitrant) seeds, respectively. Drying affects reduction and oxidation (redox) status in seeds. Oxidation of methionine to methionine sulfoxide (MetO) and reduction via methionine sulfoxide reductases (Msrs) have never been investigated in relation to seed desiccation tolerance. MetO levels and the abundance of Msrs were investigated in relation to levels of reactive oxygen species (ROS) such as hydrogen peroxide, superoxide anion radical and hydroxyl radical (•OH), and the levels of ascorbate and glutathione redox couples in gradually dried seeds. Peptide-bound MetO levels were positively correlated with ROS concentrations in the orthodox seeds. In particular, •OH affected MetO levels as well as the abundance of MsrB2 solely in the embryonic axes of Norway maple seeds. In this species, MsrB2 was present in oxidized and reduced forms, and the latter was favored by reduced glutathione and ascorbic acid. In contrast, sycamore seeds accumulated higher ROS levels. Additionally, MsrB2 was oxidized in sycamore throughout dehydration. In this context, the three elements •OH level, MetO content and MsrB2 abundance, linked together uniquely to Norway maple seeds, might be considered important players of the redox network associated with desiccation tolerance.

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Seed desiccation tolerance and dispersal in tropical dry forests in Colombia: Implications for ecological restoration

Forest Ecology and Management ◽

10.1016/j.foreco.2017.08.042 ◽

2017 ◽

Vol 404 ◽

pp. 289-293 ◽

Cited By ~ 5

Author(s):

Claudia Galindo-Rodriguez ◽

Lilia L. Roa-Fuentes

Keyword(s):

Ecological Restoration ◽

Desiccation Tolerance ◽

Tropical Dry Forests ◽

Dry Forests ◽

Seed Desiccation

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BIG COFFEE VL.: SEED DESICCATION TOLERANCE, SIEVE CLASSIFICATION, AND PHYSIOLOGICAL QUALITY

Coffee Science ◽

10.25186/cs.v13i4.1492 ◽

2018 ◽

Vol 13 (4) ◽

pp. 510 ◽

Cited By ~ 1

Author(s):

ANA CRISTINA DE SOUZA ◽

Sttela Dellyzete Veiga Franco Da Rosa ◽

Amanda Lima Vilela ◽

Madeleine Alves De Figueiredo ◽

Ana Luiza De Oliveira Vilela ◽

...

Keyword(s):

Desiccation Tolerance ◽

Seed Desiccation ◽

Physiological Quality

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Pollen and seed desiccation tolerance in relation to degree of developmental arrest, dispersal, and survival

Journal of Experimental Botany ◽

10.1093/jxb/err154 ◽

2011 ◽

Vol 62 (15) ◽

pp. 5267-5281 ◽

Cited By ~ 77

Author(s):

G. G. Franchi ◽

B. Piotto ◽

M. Nepi ◽

C. C. Baskin ◽

J. M. Baskin ◽

...

Keyword(s):

Desiccation Tolerance ◽

Developmental Arrest ◽

Seed Desiccation

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Desiccation tolerance in relation to soluble sugar contents in seeds of ten coffee (CoffeaL.) species

Seed Science Research ◽

10.1017/s0960258500000428 ◽

2000 ◽

Vol 10 (3) ◽

pp. 393-396 ◽

Cited By ~ 11

Author(s):

Nathalie Chabrillange ◽

Stéphane Dussert ◽

Florent Engelmann ◽

Sylvie Doulbeau ◽

Serge Hamon

Keyword(s):

Desiccation Tolerance ◽

Coffea Arabica ◽

High Performance ◽

Sugar Content ◽

Soluble Sugar ◽

Soluble Sugars ◽

Dry Weight ◽

Seed Desiccation ◽

Desiccation Sensitivity ◽

Coffee Species

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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What Do We Know About the Genetic Basis of Seed Desiccation Tolerance and Longevity?

International Journal of Molecular Sciences ◽

10.3390/ijms21103612 ◽

2020 ◽

Vol 21 (10) ◽

pp. 3612

Author(s):

Hanna Kijak ◽

Ewelina Ratajczak

Keyword(s):

Low Temperature ◽

Desiccation Tolerance ◽

Expression Profiles ◽

Gene Expression Profiles ◽

Seed Storage ◽

Water Losses ◽

Economic Interests ◽

Seed Desiccation ◽

Orthodox Seeds ◽

The Right

Long-term seed storage is important for protecting both economic interests and biodiversity. The extraordinary properties of seeds allow us to store them in the right conditions for years. However, not all types of seeds are resilient, and some do not tolerate extreme desiccation or low temperature. Seeds can be divided into three categories: (1) orthodox seeds, which tolerate water losses of up to 7% of their water content and can be stored at low temperature; (2) recalcitrant seeds, which require a humidity of 27%; and (3) intermediate seeds, which lose their viability relatively quickly compared to orthodox seeds. In this article, we discuss the genetic bases for desiccation tolerance and longevity in seeds and the differences in gene expression profiles between the mentioned types of seeds.

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