|
Physiological mechanism of resistance to anthracnose of
different Camellia varieties
Xinzhang, Guangdao Yang, Jie Yang and
Qinglong Shu*
School of Forest and Landscape Architecture, Anhui
Agricultural University, Hefei 230036, China.
*Corresponding author. E-mail:
qlshuau@gmail.com.
Tel: +86-551- 5786211. Fax: +86-551-5786211.
Abbreviations: PAL,
Phenylalanine ammonia lyase; PPO, polyphenol oxidase;
PR-proteins, pathogenesis-related proteins.
Accepted 29 June, 2011 |
|
Tea oil camellia (Camellia oleifera) is an important
oil-producing plant which is widely distributed in the Dabie
Mountain of Anhui province in China. Anthracnose (Colletotrichum
gloeosporioides) is a common and serious disease which
often cause flower and fruit drop in tea oil, leading to 50%
or more loss in yields. Different Camellia varieties
vary in their resistance to anthracnose. There are few
studies on the physiological mechanisms of resistance to
anthracnose. In this paper, eight different varieties of
Camellia in China were selected for measurement of the
content of four polyphenols, flavonoids, phenylalanine
ammonia lyase and polyphenol oxidase. Among the polyphenols,
catechol and salicylic acid content were related to
anthracnose resistance, with the content of the resistant
varieties been nearly five to ten times higher than that of
the more susceptible varieties. Flavonoid content was also
significantly higher in resistant varieties than in
susceptible varieties. Activities of the defense-related
enzymes phenylalanine ammonia lyase and polyphenol oxidase
did not differ between different cultivars. However, enzyme
activity of resistant cultivars improved markedly after
pathogen inoculation, while those of susceptible cultivars
did not change. This study broadens the understanding of the
mechanisms of disease resistance in Camellia.
Keywords:
Anthracnose, Camellia oleifera, phenylalanine ammonia
lyase, polyphenol oxidase. |
