Seed Treatments to Overcome Salt Stress During Germination and Seedling Growth in Switchgrass (Panicum virgatum L.).

Objective: Switchgrass was one of important bioenergy crop. The seed treatment and growth of early stage of switchgrass can influence the final yield. This study tried to investigate the effects of seed treatments to overcome salt stress during germination and seedling growth in switchgrass. Methods: The combined pretreatments including ultrasound irradiation and KNO3 soaking were used to overcome salt stress during germination and seedling growth. In addition, 9 indicators including 3 physiological indicators were investigated. Model analysis and principal components analysis (PCA) were used to integrate the indicators and build the interaction between factors and indicators. Results: The combined pretreatments were effective in terms of overcoming the salt stress of switchgrass seed. The important extents of the four treatment factors (sonication time, sonication temperature, concentration of KNO3, and time of KNO3 treatment, respectively) under salt stress were also investigated. Furthermore, a network linking the indicators and factors was established. Conclusion: The research provided a new practical treatment method to overcome the salt stress. It also offered the data basis of the switchgrass seed under the salt stress and the link between treatment, indictors, and salt stress.