Limits...
Seed dormancy, seedling establishment and dynamics of the soil seed bank of Stipa bungeana (Poaceae) on the Loess Plateau of northwestern China.

Hu XW, Wu YP, Ding XY, Zhang R, Wang YR, Baskin JM, Baskin CC - PLoS ONE (2014)

Bottom Line: Removal of palea and lemma, chemical scarification, dry storage (afterripening), gibberellin (GA3) and potassium nitrate (KNO3) significantly improved germination.Dormancy was completely released by removal of the hulls, but seeds on which hulls were put back to their original position germinated to only 46%.However, final percentage of seedling emergence did not differ significantly for seeds sown at depths of 0 and 1 cm.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, China.

ABSTRACT
Studying seed dormancy and its consequent effect can provide important information for vegetation restoration and management. The present study investigated seed dormancy, seedling emergence and seed survival in the soil seed bank of Stipa bungeana, a grass species used in restoration of degraded land on the Loess Plateau in northwest China. Dormancy of fresh seeds was determined by incubation of seeds over a range of temperatures in both light and dark. Seed germination was evaluated after mechanical removal of palea and lemma (hulls), chemical scarification and dry storage. Fresh and one-year-stored seeds were sown in the field, and seedling emergence was monitored weekly for 8 weeks. Furthermore, seeds were buried at different soil depths, and then retrieved every 1 or 2 months to determine seed dormancy and seed viability in the laboratory. Fresh seeds (caryopses enclosed by palea and lemma) had non-deep physiological dormancy. Removal of palea and lemma, chemical scarification, dry storage (afterripening), gibberellin (GA3) and potassium nitrate (KNO3) significantly improved germination. Dormancy was completely released by removal of the hulls, but seeds on which hulls were put back to their original position germinated to only 46%. Pretreatment of seeds with a 30% NaOH solution for 60 min increased germination from 25% to 82%. Speed of seedling emergence from fresh seeds was significantly lower than that of seeds stored for 1 year. However, final percentage of seedling emergence did not differ significantly for seeds sown at depths of 0 and 1 cm. Most fresh seeds of S. bungeana buried in the field in early July either had germinated or lost viability by September. All seeds buried at a depth of 5 cm had lost viability after 5 months, whereas 12% and 4% seeds of those sown on the soil surface were viable after 5 and 12 months, respectively.

Show MeSH

Related in: MedlinePlus

Effect of hulls, half-endosperm removal and NaOH scarification on germination of fresh seeds of Stipa bungeana at 20°C in dark.Different letters indicate significant difference (P<0.05) among all treatments (n = 4).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4232413&req=5

pone-0112579-g002: Effect of hulls, half-endosperm removal and NaOH scarification on germination of fresh seeds of Stipa bungeana at 20°C in dark.Different letters indicate significant difference (P<0.05) among all treatments (n = 4).

Mentions: Hulls, endosperm and scarification with NaOH had a significant effect on release of seed dormancy (P<0.05, Fig. 2). Twenty-five percent of fresh seeds (with hulls) without pretreatment germinated, and dormancy was completely released when the hulls were removed. However, seeds in which the hulls were put back to their original position germinated to a significantly lower percentage (46) than those hulls removed (94). Removal of half of the endosperm increased germination from 25% to 45% (P<0.05). Seeds treated with NaOH for 20, 40 and 60 minutes germinated to 45, 63 and 82%, respectively (Fig. 2).


Seed dormancy, seedling establishment and dynamics of the soil seed bank of Stipa bungeana (Poaceae) on the Loess Plateau of northwestern China.

Hu XW, Wu YP, Ding XY, Zhang R, Wang YR, Baskin JM, Baskin CC - PLoS ONE (2014)

Effect of hulls, half-endosperm removal and NaOH scarification on germination of fresh seeds of Stipa bungeana at 20°C in dark.Different letters indicate significant difference (P<0.05) among all treatments (n = 4).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4232413&req=5

pone-0112579-g002: Effect of hulls, half-endosperm removal and NaOH scarification on germination of fresh seeds of Stipa bungeana at 20°C in dark.Different letters indicate significant difference (P<0.05) among all treatments (n = 4).
Mentions: Hulls, endosperm and scarification with NaOH had a significant effect on release of seed dormancy (P<0.05, Fig. 2). Twenty-five percent of fresh seeds (with hulls) without pretreatment germinated, and dormancy was completely released when the hulls were removed. However, seeds in which the hulls were put back to their original position germinated to a significantly lower percentage (46) than those hulls removed (94). Removal of half of the endosperm increased germination from 25% to 45% (P<0.05). Seeds treated with NaOH for 20, 40 and 60 minutes germinated to 45, 63 and 82%, respectively (Fig. 2).

Bottom Line: Removal of palea and lemma, chemical scarification, dry storage (afterripening), gibberellin (GA3) and potassium nitrate (KNO3) significantly improved germination.Dormancy was completely released by removal of the hulls, but seeds on which hulls were put back to their original position germinated to only 46%.However, final percentage of seedling emergence did not differ significantly for seeds sown at depths of 0 and 1 cm.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, China.

ABSTRACT
Studying seed dormancy and its consequent effect can provide important information for vegetation restoration and management. The present study investigated seed dormancy, seedling emergence and seed survival in the soil seed bank of Stipa bungeana, a grass species used in restoration of degraded land on the Loess Plateau in northwest China. Dormancy of fresh seeds was determined by incubation of seeds over a range of temperatures in both light and dark. Seed germination was evaluated after mechanical removal of palea and lemma (hulls), chemical scarification and dry storage. Fresh and one-year-stored seeds were sown in the field, and seedling emergence was monitored weekly for 8 weeks. Furthermore, seeds were buried at different soil depths, and then retrieved every 1 or 2 months to determine seed dormancy and seed viability in the laboratory. Fresh seeds (caryopses enclosed by palea and lemma) had non-deep physiological dormancy. Removal of palea and lemma, chemical scarification, dry storage (afterripening), gibberellin (GA3) and potassium nitrate (KNO3) significantly improved germination. Dormancy was completely released by removal of the hulls, but seeds on which hulls were put back to their original position germinated to only 46%. Pretreatment of seeds with a 30% NaOH solution for 60 min increased germination from 25% to 82%. Speed of seedling emergence from fresh seeds was significantly lower than that of seeds stored for 1 year. However, final percentage of seedling emergence did not differ significantly for seeds sown at depths of 0 and 1 cm. Most fresh seeds of S. bungeana buried in the field in early July either had germinated or lost viability by September. All seeds buried at a depth of 5 cm had lost viability after 5 months, whereas 12% and 4% seeds of those sown on the soil surface were viable after 5 and 12 months, respectively.

Show MeSH
Related in: MedlinePlus