Seeds of tomato (L. esculentum Mill cv. Liaoyuanduoli), a popular variety in Northeast China, were germinated and grown
in 12 cm × 12 cm nutrition pots in heated greenhouses (average day/night temperatures, 25 ◦C/15 ◦C) with natural light at a relative humidity of 60% in February 2009 at the Shenyang Agricultural University. The plants were watered according to normal cultivation management.