Abstract:
Aluminum has been recognized as a toxic element for plant growth
and a great number of studies have attempted to determine the toxic
concentration of aluminum for different species. Despite decades of intensive
research, the primary cause underlying the Al toxicity syndrome in plants has
not been elucidated, even though the interaction between Al and Ca2+ is the
strongest possibility. The celular mechanism of Al toxicity and tolerance in
plant is another not yet elucidated problem. Phytotoxicity of aluminum is
characterized by an inhibition of root elongation, but the mechanisms
primarily responsible are not well understood. In this work we present our
results on response of tomato plants under aluminum stress. In order to study
the effects of aluminum cations on tomato plant development, we treated the
plants with solutions of m/1000 concentration from four salts which contain
aluminum. We monitored the dynamics of germination and the plant growth
and then we performed measurements on biologic parameters and
photosynthetic activity. Our results showed that the dynamic of germination,
shoot length, biomass, and photosynthetic activity have been affected by
aluminum treatment. Tomato plants treated with solutions of different salts
which contain Al3+ responded in a different manner to this cation. Therefore
the degree of germination was higher for untreated seeds than the treated
ones; the effects of aluminum on roots resulted in strong inhibition, and
structure damage, the most effect being for treatment with KAl(SO4)2*12H2O
and the minimal effect being for NH4Al(SO4)2*12H2O. The same effect we
can observe for biomass of tomato plants after two month and for content of
photosynthetic pigment.
