Abstract:

The research aimed to study the effect of exogenous chitosan of different quality density on lettuce seed germination under high temperature stress. This experiment adopted exogenous chitosan of different quality density to deal with the lettuce seeds and carries out the heat sprouting. The test counted the seed germination rate and the seeding height, the fresh weight and the root length of the seedling. The test measured the activities of SOD, POD, CAT and MDA content. The results have shown that lettuce seeds were treated with 30-120 mg/L of exogenous chitosan could increase the seeds germination rate, germination energy, the seeding height, the root length and the fresh weight than of the control. The activity of SOD, CAT and POD increased firstly and then decreased, the content of MDA was lower than that in control, and 60mg/L of exogenous chitosan treatment can get the optimum effect.