Regeneration of tomato

Seed dormancy

Fresh seeds may germinate irregular. After storing the seeds for about half a year the germination is normal.




Before sowing seeds are disinfected (see pepper), to avoid infection with Tobacco Mosaic Virus (TMV), other tobamo viruses and Pepino Mosaic Virus. Seeds are sown in seed trays at 23°C, generally between January and March, but it is possible to sow until July. After 10-14 days the seedlings are transplanted to rockwool blocks (12x12 cm) at a temperature of 20/15°C day/night.


About 7 weeks after sowing the plants in the rockwool blocks are placed on rockwool bags at a distance of 50 cm in the row and alternating 60 and 100 cm between the rows, at a temperature of 20/15°C day/night. The plants are grown along wires (1 stem per plant for the indeterminate types). Plants are pruned regularly, taking precautions to prevent virus transmission. During regeneration, plants are testet twice for occurrence of Pepino Mozaic Virus. About 2.5 months after sowing the plants start to flower. To improve seed set the racemes are touched with a vibrator, improving the pollination.

Per accession seven plants are used for regeneration. For cross-pollinating wild species or heterogeneous accessions up to 14 plants are used. For these species a pollen-mixture of all plants in the accession is used for hand pollination.


About 5 months after sowing the fruits start to ripen. Per plant 10 or more ripe fruits are harvested.

Pest and disease control

Biological control

  • Spider mites with Phytoseiulus persimilis
  • Thrips with Phytoseiulus persimilis and Orius laevigatus
  • White fly with Aphidus coleman
  • Aphids with Encarcia formosa

Pesticide treatments

  • Spider mites, in case biological control is not effective.