Plant material
Tomato (Solanum lycopersicum L. ‘Moneymaker’) seeds were germinated in potting soil in a growth chamber (24°C, 12/12 light/dark). Five days after emergence, seedlings were transplanted to pots containing a 3:1 (v/v) mixture of sand and sieved potting soil (Structural Type 1, Snebbout). Seedlings were watered three times a week and fertilized weekly with 30 ml of fertilizer (Soluplant NPK 19-8-16+4MgO+ME, Haifa Chemicals, 1 g l-1). Rice (Oryza sativa L. ‘Nipponbare’) seeds (GSOR-100, USDA) were grown as in Nahar et al. (2011).