TIMING IN PORTUGUESE DIRECT SEEDED TOMATOES FOR INDUSTRY

Degree-days of growth (base 6°C) were calculated for three periods of development of the tomato cultivars ‘VF145.21.4’ and ‘Cal J’. There was no significant relationship between rates of emergence and mean temperature.
A minimum of 70 degree-days were required from sowing to emergence.
The period from emergence to flower initiation bore no significant relationship to accumulated temperature.
Significant regressions between rate of development and mean temperature were established for the period from emergence to harvest.

The cultivars ‘VF145.21.4’ and ‘Cal J’ require an average of 2012 and 1993 degree-days from emergence to harvest with 90% mature fruit.
The suitability of a 6°C base temperature for the calculated degree-days of growth was confirmed.
However, there was an indication that it could be replaced by a 10°C base temperature for soils with poor water holding capacity in the warmer areas of the country.

Symposium on the Timing of Field vegetable Production

M.R. Stilwell, C.A. Portas

https://doi.org/10.17660/ActaHortic.1978.72.21