Transformation Of Potato With Arabidopsis Na~+/H~+ Antiporter Genes

Potato is one of the four major crops including wheat, corn, and rice. It is widely planted in the world due to its short growth cycle, high yield and rich nutrients. Potato yield is the fourth largest in the world after wheat, corn, and rice. Potato planting expands year by year worldwide. However, potato is sensitive to salt, which causes detrimental damage to growth, yield and quality of potato. Therefore, using genetic engineering technology to cultivate potato varieties resistant to salt stress is an urgent issue in potato production. In recent years, it has been found that plant Na+/H+ antiporters play an important role in reducing cellular Na+ and improving salt resistance. Therefore, transformation of Na+/H+ antiporter genes with genetic engineering technology is an efficient way for breeding potato varieties resistant to salt stress.Our previous study has shown that AtNHX5 and AtNHX6 genes function in maintaining cellular K+ and Na+ homeostasis in Arabidopsis. In this study, we transformed AtNHX5 and AtNHX6 genes into potato and successfully obtained the transgenic seedlings. We screened the transgenic seedlings for salt tolerance using molecular, genetic and cell biology methods.Our goal is to breed potato varieties resistant to salt stress.The major results are listed below:1. We cloned AtNHX5 and AtNHX6 genes from pDR1 96-AtNHX5 and pDR196-AtNHX6 plasmids by PCR, and constructed pUBC-AtNHX5-GFP and pUBC-AtNHX6-GFP expression vectors by the method of Gateway.2. The pUBC-AtNHX5-GFP and pUBC-AtNHX6-GFP expression vectors were transformed into four potato varieties, including "Atlantic", "Qingshu9", "Gannongshu2" and "Favorita", using the Agrobacterium-mediated method.22 positive transgenic lines were identified by PCR and GFP fluorescence.3. The transgenic seedlings grown in liquid media were tolerant to salt stress. The transgenic lines of "Atlantic" grown in flowerpots were tolerant to salt and drought stress, and had a high yield.