TY - JOUR
T1 - Germination of Artemisia sphaerocephala (Asteraceae), occurring in the sandy desert areas of Northwest China
AU - Huang, Z.
AU - Gutterman, Y.
N1 - Funding Information:
The authors wish to thank Prof. Qu Qiuyun of Shaanxi Institute for Desert Control, China, for sending us the achenes. We also thank Prof. Hu Zhenghai of Northwest University of China and Prof. Carol Baskin and Prof. Jerry Baskin of the School ofBiological Sciences, University of Kentucky, USA, for their useful comments. Mr. Zhenying Huang thanks the Blaustein International Center for supporting his living expenses with a Ph.D. fellowship. This work is part of Mr. Huang's Ph.D. thesis.
PY - 1999/1/1
Y1 - 1999/1/1
N2 - Artemisia sphaerocephala is a dominant perennial shrub in large areas of active and stabilized sands of the deserts of northwest China. A. sphaerocephala produces achenes in three colours that germinate at different rates but reach the same final germination percentages. The seeds are covered by a thick pericarp which becomes a mucilaginous layer when wetted and increases in weight 589 times by absorbing water. These achenes float on water for a long time and varying concentrations of salt solutions affect germination. The achenes germinate in light but not in dark. The optimal germination temperature is 25°C. At 10°C and 30°C germination was slow and reached low percentages. Germination was inhibited at 5°C. The deeper the achenes in sand, the lower and slower their germination. No seedlings emerged from achenes located 2 cm and deeper. However, when the upper layer of sand was removed leaving 0.5 cm, their germination reached the same percentages as the achenes located 0.5 cm deep from the beginning of wetting, but at a faster rate. The higher the sand moisture content, from 1.7% to 14.7%, the higher and earlier the germination. From 19.4% moisture content germination was delayed and seedlings remained undeveloped.
AB - Artemisia sphaerocephala is a dominant perennial shrub in large areas of active and stabilized sands of the deserts of northwest China. A. sphaerocephala produces achenes in three colours that germinate at different rates but reach the same final germination percentages. The seeds are covered by a thick pericarp which becomes a mucilaginous layer when wetted and increases in weight 589 times by absorbing water. These achenes float on water for a long time and varying concentrations of salt solutions affect germination. The achenes germinate in light but not in dark. The optimal germination temperature is 25°C. At 10°C and 30°C germination was slow and reached low percentages. Germination was inhibited at 5°C. The deeper the achenes in sand, the lower and slower their germination. No seedlings emerged from achenes located 2 cm and deeper. However, when the upper layer of sand was removed leaving 0.5 cm, their germination reached the same percentages as the achenes located 0.5 cm deep from the beginning of wetting, but at a faster rate. The higher the sand moisture content, from 1.7% to 14.7%, the higher and earlier the germination. From 19.4% moisture content germination was delayed and seedlings remained undeveloped.
KW - Achene colours
KW - Light intensity and germination in soil
KW - Mucilage-water absorption and floating
KW - Salt concentrations and sand moisture content
KW - Temperatures and light duration
UR - http://www.scopus.com/inward/record.url?scp=0032884407&partnerID=8YFLogxK
U2 - 10.1016/S0254-6299(15)30972-8
DO - 10.1016/S0254-6299(15)30972-8
M3 - Article
AN - SCOPUS:0032884407
SN - 0254-6299
VL - 65
SP - 187
EP - 196
JO - South African Journal of Botany
JF - South African Journal of Botany
IS - 3
ER -