TY - JOUR
T1 - Factors influencing seed dormancy and germination in sand, and seedling survival under desiccation, of Psammochloa villosa (Poaceae), inhabiting the moving sand dunes of Ordos, China
AU - Huang, Zhenying
AU - Dong, Ming
AU - Gutterman, Yitzchak
N1 - Funding Information:
This study was supported financially by the Key Project of Chinese Academy of Sciences (KSCX1-08-02) and the National Natural Science Foundation (30000021) of P. R. China.
Funding Information:
Dr. Zhenying Huang thanks the Blaustein International Center of Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Israel, for awarding him a post-doctoral fellowship.
PY - 2004/2/1
Y1 - 2004/2/1
N2 - Psammochloa villosa (Trin.) Bor. (Poaceae), is distributed primarily in moving sand dunes of the Ordos Plateau, China. Freshly harvested caryopses (seeds) are in non-deep physiological dormancy (non-deep PD). Germination is slow and low and only over a narrow temperature range. A treatment of four weeks cold stratification at 3 to 5°C in darkness was required to break non-deep PD, allowing germination to reach high percentages at higher temperatures and without light requirement. Rate and percentages of germination were increased by scarifying the caryopsis coat and by artificial removal of different proportions of the endosperm. However, seedling dry weight and increases in root and shoot lengths, were significantly influenced by the proportion of the endosperm that remained on the caryopses. Higher percentages of seedling emergence were obtained from the shallowly buried caryopses, ranging from 0.5-2.0 cm, and the depth of the caryopses in the sand affected the time of germination. The deeper the caryopses were buried, the more that remained ungerminated and in enforced dormancy. The caryopses germinated when the upper sand layer was removed and buried caryopses were at a suitable sand depth for germination, or when the sand was aerated. In natural habitats, germinated seedlings may be wholly exposed to the air by sand erosion and thus be exposed to drought stress. However, young seedlings have the ability to tolerate desiccation and to recover after rehydration. Root length at the 'point of no return' is 4 mm.
AB - Psammochloa villosa (Trin.) Bor. (Poaceae), is distributed primarily in moving sand dunes of the Ordos Plateau, China. Freshly harvested caryopses (seeds) are in non-deep physiological dormancy (non-deep PD). Germination is slow and low and only over a narrow temperature range. A treatment of four weeks cold stratification at 3 to 5°C in darkness was required to break non-deep PD, allowing germination to reach high percentages at higher temperatures and without light requirement. Rate and percentages of germination were increased by scarifying the caryopsis coat and by artificial removal of different proportions of the endosperm. However, seedling dry weight and increases in root and shoot lengths, were significantly influenced by the proportion of the endosperm that remained on the caryopses. Higher percentages of seedling emergence were obtained from the shallowly buried caryopses, ranging from 0.5-2.0 cm, and the depth of the caryopses in the sand affected the time of germination. The deeper the caryopses were buried, the more that remained ungerminated and in enforced dormancy. The caryopses germinated when the upper sand layer was removed and buried caryopses were at a suitable sand depth for germination, or when the sand was aerated. In natural habitats, germinated seedlings may be wholly exposed to the air by sand erosion and thus be exposed to drought stress. However, young seedlings have the ability to tolerate desiccation and to recover after rehydration. Root length at the 'point of no return' is 4 mm.
KW - Germination at sand depths
KW - Non-deep physiological dormancy
KW - Rehydration
KW - Removal of endosperm
KW - Scarification
KW - Seedling desiccation tolerance
UR - http://www.scopus.com/inward/record.url?scp=1842809946&partnerID=8YFLogxK
U2 - 10.1023/B:PLSO.0000020971.66784.fc
DO - 10.1023/B:PLSO.0000020971.66784.fc
M3 - Article
AN - SCOPUS:1842809946
SN - 0032-079X
VL - 259
SP - 231
EP - 241
JO - Plant and Soil
JF - Plant and Soil
IS - 1-2
ER -