Joint International Conference on Long-term Experiments ...

STUDIES REGARDING THE INFLUENCE OF SALICYLIC ACID ON THE
GERMINATION OF MAIZE CARYOPSIS (Zea Mays) AND ON THE
PEROXIDASE ACTIVITY IN MAIZE PLANTLETS
Cornelia Purcarea*, Dorina Cachita-Cosma **
University of Oradea, Faculty for Environmental Sciences*
Uiversity of Oradea, Faculty of Sciences**
ABSTRACT
In this paper we studied the influence of exogenous salicylic acid administration in
different concentrations (0.1mg/l, 1.0mg/l, 5.0mg/l), on maize caryopsis germination in
comparison with the germination of control lots, wich was not treated with salicylic
acid., and on the peroxidase activity in the maize plantlets resulted after 72, 96 and 120
hours of germination. The results showed that the exogenous salicylic acid reduced the
germination capacity of the maize caryopsis germination as compared to that of the
reference lots, and intesified with 6.8 and 9.06% the peroxidase activity in the roots and
with 5% in coleoptiles at 1.0 mg/l concentration of the maize plantlets. The exogenous
salicylic acid influences was dependent on the concentration wich was used.
Keywords: salicylic acid, maize, germination, peroxidase activity.
1./ INTRODUCTION
Salicylic acid (SA) that was named after Salix plant (willow), was first discovered as a
major component in the extracts from willow tree bark that had been used as a natural
anti-inflammatory drug from the ancient time to the 18th century. The name SA, from
the Latin word Salix for willow tree, was given to this active ingredient of willow bark
by Raffaele Piria in 1838 (Raskin, 1992)
The salicylic acid or o-hydroxibenzoic acid, nowadays considered to be an
important signal molecule, involved in the development process of plants (Ryan and
Farmer, 1992). Actually, SA is considered a plant growth regulator, which influences
many of the vegetal processes, such as: germination (Cutt and Klessig, 1992), stomatal
behaviour (Larque-Saaveda, 1979), membrane permeability (Barkosky and Einhellig,
1993), rate of photosynthesis (Khan and Prithiviraj, 2003), etc. In 1974, Cleland and
Ajami, proved that the SA has an endogeneous regulator of flowering.
In the opinion of Handro et al., (1997), the SA supports flowering and tuberization
of plants. They studied the in vitro effect of SA of flowering of Streptocarpus nobilis,
but also of in vitro tuberization of Ullucus tuberosus. In the presence of 0,5-2,0 μM SA
the number of Streptocarpus nobilis floral buds significantly increased and floral
scapes were significantly longer as compared with the controls cultured without SA..
Picomolar levels of SA, enhance cell growth and the embryogenesis in the cell
suspension cultures of Coffea arabica,as compared with entreated control cultures
(Quiroz-Figueroa et al. 2001). They reached the conclusion that SA can activate as a
morphoregulator signal, wich supports the hypothesis that SA is functioning as a growth
regulator. The authors also suggested that it is possible that this phenolic compounds act
as a signal to induce the differentiation processes. An alternative explanation is the
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