商品簡介
In Tunisia, geothermal water is an important source of energy for greenhouses, firstly for heating and secondly for irrigating crops. However, damage can be caused to the root system when the temperature exceeds 38 C at ground level, hence the theme of root thermal stress. The aim of the present study is to assess the tolerance of the 'Roma' tomato variety to this stress on the basis of physiological and biochemical parameters. At the end of the sixth leaf stage, hydroponically-grown tomato plants underwent various thermal shocks at substrate level of 35 C, 39 C and 45 C, in the presence of a control batch placed at 25 C. Harvesting took place 1, 3 and 6 days after heat treatment. The results show growth stimulation at a root temperature of 35 C. On the other hand, a depressive effect on growth was recorded at root temperatures of 39 C and 45 C. Thus, raising the substrate temperature from 25 C to 35 C is optimal for tomatoes, whereas 39 C and 45 C are not tolerated.
