Performance of transgenic petunia x hybrida plants containing the psag12-ipt gene grown under nutritional deficiency.
Nutritional deficiency in plants can causes
chlorosis, necrosis, defoliation, reduced growth, reduced
yield, and premature senescence. Exogenous
applications of cytokinin can alleviate these symptoms.
This study was conducted to evaluate the effects
of an auto regulated cytokinin production on
the nutritional deficiency tolerance in Petunia x
hybrida plants. A chimeric gene of the senescencespecific
SAG12 promoter and the ipt gene coding
for isopentenyl transferase, a rate-limiting enzyme
in the cytokinin biosynthesis pathway, was introduced
into Petunia x hybrida plants byAgrobacterium-mediated transformation. Two
transgenic plants containing the ipt gene were selected
and self-pollinated to obtain the lines evaluated
for nutritional deficiency tolerance analysis.
Both transgenic PSAG12–ipt lines analyzed were more
tolerant to nutritional deficiency than wild-type
plants. The results indicated that endogenous cytokinin
can counteract nutritional deficiency symptoms.