Alleviation of Phytophthora capsici-induced oxidatıve stress by foliarly applied proline in Capsicum annuum L.
Phytophthora capsici is a highly destructive pathogen of pepper. To examine whether proline modifies the levels of plant defense compounds produced in response to P. capsici-induced stress, pepper seedlings were infected with P. capsici-22 in the presence of proline (1 mM, 10 mM) or in its...
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
University of Belgrade, University of Novi Sad
2017-01-01
|
| Series: | Archives of Biological Sciences |
| Subjects: | |
| Online Access: | http://www.doiserbia.nb.rs/img/doi/0354-4664/2017/0354-46641600133K.pdf |
| Summary: | Phytophthora capsici is a highly destructive pathogen of pepper. To examine
whether proline modifies the levels of plant defense compounds produced in
response to P. capsici-induced stress, pepper seedlings were infected with P.
capsici-22 in the presence of proline (1 mM, 10 mM) or in its absence.
Proline was sprayed on the leaves of CM-334 and Kekova pepper cultivars prior
to inoculation. CM-334 was more resistant to P. capsici-22, while the Kekova
cultivar exhibited a sensitive reaction. P. capsici-22 increased the total
phenolic compound and H2O2 levels, as well as phenylalanine ammonia-lyase,
polyphenol oxidase and peroxidase activities in pepper seedlings. The
application of exogenous proline further increased the activities of
phenylalanine ammonia-lyase, polyphenol oxidase and peroxidase, as well as
the total levels of phenolic compounds and the fresh and dry weights of the
plants on the 5th and 7th days post treatment. After proline application, the
highest catalase activity was found in both cultivars on the 5th day of the
10 mM proline + P. capsici application. On all days of the experiment, the
applications caused a decrease in disease severity, necrosis length and H2O2
levels in both cultivars. In addition, proline decreased the colony growth of
P. capsici and the number of zoospores. This finding indicates that enzymes
and total phenolic compound levels protect the pepper seedlings against
stress-related damage. Moreover, proline has the potential to directly
scavenge free radicals and promote enzyme activity in pepper seedlings under
P. capsici stress. These results suggest that foliar application of proline
is an effective way to improve the stress tolerance of pepper to P. capsici. |
|---|---|
| ISSN: | 0354-4664 1821-4339 |