Abstract
In this study, in planta transformation of tomato (
Solanum lycopersicum
L.), using fruit injection and floral dip, is reported.
Agrobacterium tumefaciens
strain EHA 105 containing one of three constructs, i.e., pROKIIAP1GUSint (carrying the
Apetala 1
[
AP1
] gene), pROKIILFYGUSint (carrying the
LEAFY
[
LFY
] gene), or p35SGUSint (carrying the
β-glucuronidase
[
GUS
] gene), was used for plant transformation. For fruit injection transformation, no significant effects (
p
> 0.05) of the construct used were observed. The highest frequency of transformation was obtained following 48-h incubation of tomato fruit with bacterial cells harboring either one of the three constructs; transformation frequencies of 17%, 19%, and 21% for
AP1
,
LFY
, and
GUS
gene constructs, respectively, were obtained. When fruit maturity was evaluated in fruit injection experiments, mature red fruit resulted in higher frequency of transformants than immature green fruit with 40%, 35%, and 42% for
AP1
,
LFY
, and
GUS
gene constructs, respectively. For floral dip transformation, a higher number of transformants was obtained when the
GUS
gene construct was used instead of either the
AP1
or
LFY
gene construct, thus suggesting a possible inhibitory effect of the flowering genes used. When flowers were transformed prior to rather than following pollination, they yielded a higher transformation frequency, 12% for the
LFY
construct and 23% for the
GUS
construct (
p
< 0.05), although no transformant was obtained with the
AP1
gene construct. All putative GUS-positive transformants were analyzed using polymerase chain reaction and confirmed for the presence of the transgene. Compared to control plants, transgenic plants carrying either the
AP1
or
LFY
transgene flowered earlier and showed several different morphological characters.