Liečivé rastliny v meniacich sa environmentálnych podmienkach

Vliv biotických a abiotických stresorů na vlastnosti rostlin 11.5.2005
Localization of active oxygen species and study of antioxidant enzymes
in Lactuca spp. during pathogenesis of Bremia lactucae (causal agent
of lettuce downy mildew)
Key words: active oxygen species – peroxidases – superoxide dismutase – catalase – resistance
– Lactuca spp. – Bremia lactucae
Six genotypes of four Lactuca spp. with different phenotypes of expression of interaction with
Bremia lactucae (race NL 16) were subjected to histochemical detection of molecules involved in
oxidative stress. Time-course studies of antioxidant enzymes activity changes – peroxidase (POX),
catalase (CAT), superoxide dismutase (SOD) were also involved. 6 to 96 hours after inoculation
(hai) histochemical methods revealed no dramatic changes in H 2 O 2 and peroxidase (POX)
distribution among genotypes of L. sativa and L. serriola. In resistant genotypes, stronger
accumulation of H 2 O 2 occurred 48 to 96 hai. Prompt formation and extensive spread of H 2 O 2
characterize resistance of L. virosa (consistent with phenotypic expression by HR). There was
observed relationship between timing of H 2 O 2 accumulation and POX activation. The absolute
values of enzyme activities in resistant wild Lactuca spp. were approximately twice higher when
compared to others. Superoxide was not assessed histochemically in any of studied genotypes.
Poděkování
Práce vznikla za podpory projektu GAČR 522/02/D011 a výzkumného záměru MSM 6198959215.
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