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Relationship between jasmonic acid accumulation and
senescence in drought-stress
Ge Yun-xia1,2, Zhang Li-jun1, Li
Feng-hai2, Chen Zhi-bin2, Wang Che1,
Yao Yun-cong3, Han Zhen-hai4, Zhang
Jie3 and Shi Zhen-sheng2*
1College
of Biotechnology, Shenyang Agricultural University, Shenyang
110161, People’s Republic of China.
2College of Agronomy, Shenyang Agricultural
University, Shenyang 110161, People’s Republic of China.
3Department of Plant Science and Technology,
College of Beijing Agriculture, Beijing 102206, People’s
Republic of China.
4Institute for Horticultural Plants, College of
Agriculture and Biotechnology, China Agricultural
University, Beijing 100094, People’s Republic of China.
*Corresponding author. E-mail:
shi.zhensheng@163.com,
geyunxia3@163.com. Tel: 86-13804036545.
Accepted 26 June, 2010 |
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Plants raised
from shoot-tip cultures of apricot (DT: drought-tolerant
genotype Prunus armeniaca L. cv. Ansu Maxim, and DS:
drought-sensitive genotype P. armeniaca L. cv.
Longwangmao) were grown in pots of peat-based compost. Water
was withheld for 12 days. Gas chromatography–mass
spectrometry analysis indicated that jasmonic acid (JA)
levels in leaves of DT plants increased three-fold on day 12
after water was withheld, while there was little variation
in leaf JA in DS plants for the whole drying period. There
was no significant difference in the JA concentration in
roots of the two apricot cultivars from 1 – 9 days. JA
concentration in DT plants roots increased slightly by 12
days compared to JA concentration in DS. There was 100%
abscission in DT plants at 13 days, earlier than 14 days for
DS. Two months after rewatering, 12 of the 18 DT plants were
alive, but all 18 DS plants were dead. Exogenous JA
accelerated leaf senescence in both DT and DS plants by
chlorophyll loss. After JA treatment there were increased
malondialdehyde (MDA) levels in DT and DS plants. These
results suggest that the transient JA accumulation from DT
leaves may promote leaf senescence due to soil drying, thus
avoiding excessive water loss, and aiding drought survival.
Key words: Apricot, drought stress, leaf, jasmonic
acid, senescence. |