Proanthocyanidins in seed coat’s tegmen and endospermic cap inhibit seed germination in the bioenergy plant Sapium sebiferum

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1 School of Forestry and Landscape Architecture, Anhui Agriculture University, Hefei, Anhui, China
2 Key laboratory of high magnetic field and Ion beam physical biology，Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, China
DOI
10.7287/peerj.preprints.3514v1
Published
Accepted
Subject Areas
Agricultural Science, Plant Science
Keywords
Sapium sebiferum, seed dormancy, tegmen, endospermic cap, proanthocyanidins, ABA, GA
Copyright
© 2018 Shah et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Shah FA, Ni J, Chen J, Wang Q, Liu W, Chen X, Tang C, Fu S, Wu L. 2018. Proanthocyanidins in seed coat’s tegmen and endospermic cap inhibit seed germination in the bioenergy plant Sapium sebiferum. PeerJ Preprints 6:e3514v1

Abstract

Sapium sebiferum, a highly ornamental and bioenergy plant, is propagated by seed. Its seed coat contains germination inhibitors and needs long time stratification for germination. In this experiment, we discovered that S. Sebiferum seed coat (especially tegmen) and endospermic cap contained high levels of proanthocyanidins (PAs). Seed coat and endospermic cap removal induced seed germination whereas exogenous application with seed coat extract (SCE) or PAs significantly inhibited this process, suggesting that PAs in the seed coat played a major role in regulating seed germination in S. sebiferum. We further investigated how seed coat extract affected the expression of the seed germination-related genes. The results showed that SCE treatment upregulated the transcription level of the dormancy-related gene, abscisic acid (ABA) biosynthesis and signalling genes and gibberellins (GA) suppressing genes. SCE decreased the transcript levels of ABA catabolic, GA biosynthesis, reactive oxygen species (ROS) and nitrates signalling genes. Exogenous application of nordihydroguaiaretic acid (NDGA), gibberellic acid (GA3), hydrogen peroxide (H2O2) and potassium nitrate (KNO3) recovered seed germination in SCE supplemented medium. In this experiment, we highlighted the role of PAs, and its interactions with the other germination regulators, in the regulation of seed dormancy in S. Sebiferum.

Author Comment

This is a submission to PeerJ for review.

Supplemental Information

Impact of sulfuric acid stratification on seed germination of Sapium sebiferum

A, B, C, D, E, F and G are 0-(control), 10-, 20-, 30-, 40-, 50- and 60 minutes incubation in concentrated sulfuric acid respectively. Ten seeds of every treatment were sown in each 10×10 cm pot with 5 replicates. Photographs were taken after one month of seed sowing.

DOI: 10.7287/peerj.preprints.3514v1/supp-1

Effect of SCE and PAs on seed germination of S. Sebiferum

A, 0.5×MS (control). B, 0.3% SCE+0.5×MS. C, 0.1% PAs+0.5×MS. For each treatment, twelve seeds were sown in a 9 diameter cm Petri plate separately. All treatments were replicated 5 times. The Photographs were taken on the 7th day of imbibition. Bar = 2cm

DOI: 10.7287/peerj.preprints.3514v1/supp-2

Germination promoters recovered the seed germination sown in half MS supplemented with seed coat extract

A, control (sterile water). B, 50 μΜ GA3. C, 50 μΜ NDGA. D, 20 mM H2O2 and E, 0.4% KNO3 priming overnight at room temperature and the primed seed of all treatments were grown separately on 0.3% SCE+0.5×MS in 9 cm Petri plates (12 seeds per plate) for 7 days. These photographs were taken on the 7th day of imbibition. Bars = 1 cm >

DOI: 10.7287/peerj.preprints.3514v1/supp-3

List of primers used for qPCR

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Full length genes sequences with translated CDS

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water uptake percentage

Time, Scarification time. WUT, water uptake(%). Data was take 72 hours after imibibition

DOI: 10.7287/peerj.preprints.3514v1/supp-6

Effect of H2SO4 scarification time on seed germination

Treatment, H2SO4 scarification time. Germination, germination(%)

DOI: 10.7287/peerj.preprints.3514v1/supp-7

Root and shoot length of seedlings produced from H2SO4 scarified seed

Time, H2SO4 scarification time. Root, root length (cm). Shoot, shoot length (cm)

DOI: 10.7287/peerj.preprints.3514v1/supp-8

Effect of H2SO4 scarification time on PAs contents of seed coat

IT, H2SO4 scarification time. PAS, PAs contents (%) of seed coat after H2SO4 scarification

DOI: 10.7287/peerj.preprints.3514v1/supp-9

Datasheet of fig.5, 6 and 7

Data shows the delta C value of each gene. IDS, imbibition days

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PAs contents in seed coat extract, testa and tegemen

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PAs and SCE effect on seed germination

SCE and PAs were added in half MS. Data was taken after 7 days of imbibition

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Data sheet of Figure 8 Impact of germination promoters

Germination, germination (%)

DOI: 10.7287/peerj.preprints.3514v1/supp-13