Seed Priming with Proline and Glycine Betaine Enhances Germination and Seedling Growth of Maize (Zea mays) Under Chilling Stress

Abstract

Abiotic stresses like drought, salinity, cold are not desirable for successful crop production. However, successful crop production faces abiotic stresses due to changing environment. Among the abiotic stresses, chilling is a common and destructive stress to crop production. Maize is one of the most demanding cereal crop and germination of maize seeds and their growth is severely interrupted by extreme low temperature or chilling stress (CS). Seed priming with different signaling molecules confer abiotic stress like chilling. The present research was carried out to ameliorate the chilling-inhibited germination and seedling growth of maize by seed priming with proline (Pro) and glycine betaine (GB). Results showed that CS significantly reduced maize seed germination and survival rate, shoot and root length, shoot and root weight, and photosynthetic pigments, chlorophyll (Chl) a, Chl b, and total Chl contents. Seed priming with Pro and GB has a positive impact on germination and survival rate, shoot and root length, shoot and root weight and photosynthetic pigments of leaf under CS. Among the treatments, Pro and GB at 20 mM and warm water performed better; while priming with tap water and Pro and GB at 10 mM showed insignificant performance over control but significant over stress in most of the parameters. Thus, priming may be an effective tool to increase seed germination, better maize seedling growth under cold chilling stress, and proline or betaine (at 20 mM) or warm water priming (at 45 ⁰C for 5 min) can be considered as an effective priming agent