Genetically modified eggplants (aubergines) shown to be 30% more productive

Research, published in the online journal, BMC Biotechnology shows how researchers in Italy have used genetically modified eggplants made by the introduction of a gene that increases the level of the plant hormone indole acetic acid (IAA) to produce seedless fruits. Furthermore, these genetically modified eggplants are 30-35% more productive than conventional varieties in both greenhouse and field trials.

The public have a special liking for seedless fruits for two reasons, firstly seeds are often hard and unpalatable and secondly, since seed cavities are filled with fruit tissues instead of seeds, they get more fruit for their money. Consequently there is a great deal of interest in producing seedless fruit in agriculture.

Previous studies have shown that the application of IAA, to flower buds (the part of a plant from which fruits develop) can stimulate the development of fruit in the absence of fertilisation. This technique produces seedless fruit, but it is expensive because of the cost of the IAA and the labour required to treat the flower buds.

The researchers from Italy used genetic engineering to make eggplants produce seedless fruit spontaneously. This was done by inserting a gene, which codes for a molecule involved in the production of IAA that was only “turned on” in the flower buds. It is critical that IAA production was confined to the flower buds as this hormone is involved in a range of different processes in other parts of the plant such as the response of the plant to light and gravity. This specificity was achieved by combining DNA from two genes, one that contained the instructions of how to make the molecule that is needed to manufacture IAA and a second that contained the information that tells the plant to only produce this molecule in the cells located in the flower buds.

The researchers carried out three trials, two of which were conducted in greenhouses and one in an open field site in central Italy. They compared the weight of the eggplant harvest from the genetically engineered plants with eggplants that had not been genetically modified and found increased production of fruit in their genetically modified eggplants in all three trials.

From an economic standpoint the genetically modified eggplants have three major advantages over conventional varieties. Firstly, they produce more fruit with an overall increase in productivity of at least 30-35%. Secondly, the cultivation costs of producing seedless fruit was reduced and finally the genetically modified eggplants could produce fruit in conditions normally considered too cool for fruit production.