Limits...
Genetically modified parthenocarpic eggplants: improved fruit productivity under both greenhouse and open field cultivation.

Acciarri N, Restaino F, Vitelli G, Perrone D, Zottini M, Pandolfini T, Spena A, Rotino G - BMC Biotechnol. (2002)

Bottom Line: The iaaM gene codes for tryptophan monoxygenase and confers auxin synthesis, while the DefH9 controlling regions drive expression of the gene specifically in the ovules and placenta.The main advantages of DefH9-iaaM eggplants are: i) improved fruit productivity (at least 30-35%) under both greenhouse and open field cultivation; ii) production of good quality (marketable) fruits during different types of cultivation; iii) seedless fruit with improved quality.Such advantages have been achieved without the use of either male or female sterility genes.

View Article: PubMed Central - HTML - PubMed

Affiliation: Research Institute for Vegetable Crops, Monsampolo del Tronto, AP, Italy. acciarri@libero.it

ABSTRACT

Background: Parthenocarpy, or fruit development in the absence of fertilization, has been genetically engineered in eggplant and in other horticultural species by using the DefH9-iaaM gene. The iaaM gene codes for tryptophan monoxygenase and confers auxin synthesis, while the DefH9 controlling regions drive expression of the gene specifically in the ovules and placenta. A previous greenhouse trial for winter production of genetically engineered (GM) parthenocarpic eggplants demonstrated a significant increase (an average of 33% increase) in fruit production concomitant with a reduction in cultivation costs.

Results: GM parthenocarpic eggplants have been evaluated in three field trials. Two greenhouse spring trials have shown that these plants outyielded the corresponding untransformed genotypes, while a summer trial has shown that improved fruit productivity in GM eggplants can also be achieved in open field cultivation. Since the fruits were always seedless, the quality of GM eggplant fruits was improved as well. RT-PCR analysis demonstrated that the DefH9-iaaM gene is expressed during late stages of fruit development.

Conclusions: The DefH9-iaaM parthenocarpic gene is a biotechnological tool that enhances the agronomic value of all eggplant genotypes tested. The main advantages of DefH9-iaaM eggplants are: i) improved fruit productivity (at least 30-35%) under both greenhouse and open field cultivation; ii) production of good quality (marketable) fruits during different types of cultivation; iii) seedless fruit with improved quality. Such advantages have been achieved without the use of either male or female sterility genes.

Show MeSH

Related in: MedlinePlus

Expression analysis of the DefH9-iaaM gene by competitive RT-PCR during flower and fruit development. Untransformed plant (lane 1); 5, 8, 12 mm long flower buds (lanes 2, 3, 4, respectively); 40 mm long hand-pollinated fruit (lane 5); 280 mm long emasculated fruit (lane 6). An internal standard of 351 bp is present in all lanes.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC101493&req=5

Figure 3: Expression analysis of the DefH9-iaaM gene by competitive RT-PCR during flower and fruit development. Untransformed plant (lane 1); 5, 8, 12 mm long flower buds (lanes 2, 3, 4, respectively); 40 mm long hand-pollinated fruit (lane 5); 280 mm long emasculated fruit (lane 6). An internal standard of 351 bp is present in all lanes.

Mentions: The DefH9 gene is expressed specifically in the placenta and ovules during early phases of flower development [6]. To determine whether expression of the DefH9-iaaM gene also occurs during later stages of fruit growth and whether it is influenced by pollen fertilization, mRNA from transgenic flowers and fruits obtained either from emasculated or hand pollinated flowers was analyzed by RT-PCR at different stages of development, until the fruit attained a length of 28 cm. An amplicon of 161 bp corresponding to the spliced DefH9-iaaM mRNA was detected in all stages analyzed (Fig. 3, lanes 2–6). Thus, the presence of the mRNA of the DefH9-iaaM gene and consequently its action is most likely not limited to early stages of flower and fruit development. Pollination did not affect the steady state level of DefH9-iaaM mRNA (Fig. 3, compare lane 5 and lane 6).


Genetically modified parthenocarpic eggplants: improved fruit productivity under both greenhouse and open field cultivation.

Acciarri N, Restaino F, Vitelli G, Perrone D, Zottini M, Pandolfini T, Spena A, Rotino G - BMC Biotechnol. (2002)

Expression analysis of the DefH9-iaaM gene by competitive RT-PCR during flower and fruit development. Untransformed plant (lane 1); 5, 8, 12 mm long flower buds (lanes 2, 3, 4, respectively); 40 mm long hand-pollinated fruit (lane 5); 280 mm long emasculated fruit (lane 6). An internal standard of 351 bp is present in all lanes.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC101493&req=5

Figure 3: Expression analysis of the DefH9-iaaM gene by competitive RT-PCR during flower and fruit development. Untransformed plant (lane 1); 5, 8, 12 mm long flower buds (lanes 2, 3, 4, respectively); 40 mm long hand-pollinated fruit (lane 5); 280 mm long emasculated fruit (lane 6). An internal standard of 351 bp is present in all lanes.
Mentions: The DefH9 gene is expressed specifically in the placenta and ovules during early phases of flower development [6]. To determine whether expression of the DefH9-iaaM gene also occurs during later stages of fruit growth and whether it is influenced by pollen fertilization, mRNA from transgenic flowers and fruits obtained either from emasculated or hand pollinated flowers was analyzed by RT-PCR at different stages of development, until the fruit attained a length of 28 cm. An amplicon of 161 bp corresponding to the spliced DefH9-iaaM mRNA was detected in all stages analyzed (Fig. 3, lanes 2–6). Thus, the presence of the mRNA of the DefH9-iaaM gene and consequently its action is most likely not limited to early stages of flower and fruit development. Pollination did not affect the steady state level of DefH9-iaaM mRNA (Fig. 3, compare lane 5 and lane 6).

Bottom Line: The iaaM gene codes for tryptophan monoxygenase and confers auxin synthesis, while the DefH9 controlling regions drive expression of the gene specifically in the ovules and placenta.The main advantages of DefH9-iaaM eggplants are: i) improved fruit productivity (at least 30-35%) under both greenhouse and open field cultivation; ii) production of good quality (marketable) fruits during different types of cultivation; iii) seedless fruit with improved quality.Such advantages have been achieved without the use of either male or female sterility genes.

View Article: PubMed Central - HTML - PubMed

Affiliation: Research Institute for Vegetable Crops, Monsampolo del Tronto, AP, Italy. acciarri@libero.it

ABSTRACT

Background: Parthenocarpy, or fruit development in the absence of fertilization, has been genetically engineered in eggplant and in other horticultural species by using the DefH9-iaaM gene. The iaaM gene codes for tryptophan monoxygenase and confers auxin synthesis, while the DefH9 controlling regions drive expression of the gene specifically in the ovules and placenta. A previous greenhouse trial for winter production of genetically engineered (GM) parthenocarpic eggplants demonstrated a significant increase (an average of 33% increase) in fruit production concomitant with a reduction in cultivation costs.

Results: GM parthenocarpic eggplants have been evaluated in three field trials. Two greenhouse spring trials have shown that these plants outyielded the corresponding untransformed genotypes, while a summer trial has shown that improved fruit productivity in GM eggplants can also be achieved in open field cultivation. Since the fruits were always seedless, the quality of GM eggplant fruits was improved as well. RT-PCR analysis demonstrated that the DefH9-iaaM gene is expressed during late stages of fruit development.

Conclusions: The DefH9-iaaM parthenocarpic gene is a biotechnological tool that enhances the agronomic value of all eggplant genotypes tested. The main advantages of DefH9-iaaM eggplants are: i) improved fruit productivity (at least 30-35%) under both greenhouse and open field cultivation; ii) production of good quality (marketable) fruits during different types of cultivation; iii) seedless fruit with improved quality. Such advantages have been achieved without the use of either male or female sterility genes.

Show MeSH
Related in: MedlinePlus