Studies on Change of Peel Cell Ultrastructure and Disease Resistance in Harvested Tomato Fruit by UV-C Irradiation

In order to reveal the effect of UV-C irradiation on the base of cell structure among mechanism of inducing disease resistance in postharvest fruits and vegetables,the change of peel cell ultrastructure and infection inoculation of Alternaria in harvested green tomato fruits JIAFEN 15 irradiated by 2.4 kJ/m2 UV-C were studied when storied at 24℃ at the 4th and 8th day.The results showed that disintegration and senescence of the cell organelle such as chloroplast in treated tomato peel cell were delayed as compared to the control.The cell wall and cell matrix of the fruit treated with UVC showed to be thick and had high electron-opaque.Infection inoculation of irradiated fruits by UV-C was reduced 31.67 percentage point significantly compared to the control after inoculation 3 d and was reduced 15.27 percentage point after 10 d,the disease index was reduced 16.90 at the 10th.Disease resistance and defence of cell wall of 2.4 kJ/m2 UV-C treated fruits were enhanced.