Effect of high temperature on seed vigor of Litchi

The article studied the germination rate, germination energy, seed vigor index, relative radicle length and budding days of Litchi under the condition of 40~52 and normal temperature to germinate one day and storage at normal temperature for 46 days. The results showed that high temperature had obvious effect on seed vigor, the temperature of germinate more than 46 could inhibit seed germination rate and germination energy. Seed vitality was more sensitive to germination temperature than germination rate and germination energy, seed vigor significantly decreased when the germination temperature was more than 44 . The seed had ability to resist high temperature, which could improve the seed vigor. Seed germination time was most sensitive to the germination temperature, the temperature of germinate more than 42益could inhibit seedling emergence. Therefore, it infers that the critical high temperature of seed germination is 42.