The Effect of 1-Methylcyclopropene Application Incorporated with Packaging on the Expression of Ethylene-related Genes and Quality Maintenance of Cherry Tomato Cultivars

Longevity of 4 Cherry tomato cultivars as the perishable climacteric fruit and the expression of ethylene biosynthesis genes (SAM1, ACS4, ACO1 and ACO4) under packaging (LDPE film) and 1-MCP plus packaging (5 µL L-1 for 48 h at 20 °C) treatments at 20 °C for 16 days were studied. The results of weight loss and firmness showed that there is no remarkable difference between packaging and 1-MCP plus packaging in 4 tomato cultivars, but the fluctuations of TSS and pH were more minor in 1-MC P plus packaging compared to the other treatments. Base on the physicochemical characteristics and quality maintenance, cultivars were graded from high to low durability; yellow pear, orang santa, blackberry and orange berry, respectively. The study of expression pattern of genes SAM1, ACS4, ACO1 and ACO5 in yellow pear and orange berry cultivars at storage showed that they were drastically expressed higher in control than packaging and 1-MCP plus packaging treatments. The expression level of ACO5 gene was the same in both cultivars, but the expression level of ACO1 and ACS4 genes in the yellow pear cultivar was higher than the orange berry. In contrast, the expression level of SAM1 gene in the yellow pear cultivar was lower than the orange berry. Totally, despite being deeply different in the genetic background of these cultivars, packaging and 1-MCP plus packaging treatment reduced the perishability, and improved the maintenance quality of cherry tomato fruit. Also, further molecular studies and evaluation of ethylene in these cultivars are suggested.