Environmental Science Archives (2025) Vol. IV Issue 1 DOI: 10.5281/zenodo.14748200 72 www.envsciarch.com Post Germination Desiccation Tolerance as the Marker of Drought Tolerance in Wheat (Triticum aestivum L.) Palvi Singla 1 , Vikramjit Kaur Zhawar 1 * and Johar Singh 2 1 Department of Biochemistry, College of Basic Sciences and Humanities, Punjab Agricultural University, Ludhiana, Punjab, India. 2 Department of Plant Breeding and Genetics, College of Agriculture, Punjab Agricultural University, Ludhiana, Punjab, India. *Correspondence for materials should be addressed to VKZ (email: vikram97jit@pau.edu) Abstract Desiccation tolerance (DT) withstands extreme dehydration (90-95% water loss). Post-gemination DT is one of three types of DT known to be present in angiosperms. Wheat possesses post- germination DT. Present study found post-germination DT superior in drought tolerant cultivar than drought susceptible cultivar. Further investigation demonstrated that grades of phenolics, lignin, anthocyanins, gamma-amino butyric acid (GABA), proline, sugars and starch and activities of guaiacol peroxidase, glutathione peroxidase, sucrose phosphate synthase, sucrose synthase, and amylases were linked to the post-germination-DT of drought tolerant compared to drought susceptible cultivar. Results concluded that post-germination DT can be the marker of drought tolerance in wheat. Antioxidants, proline, sugars, and GABA may be the chief players involved in post-germination DT in wheat. Keywords: Wheat; Desiccation; Tolerance; Gamma-amino butyric acid; Glutathione; Peroxidase; Starch; Sucrose synthase Introduction Desiccation tolerance (DT) is the ability of living cells to deal with water loss below 0.1 g H2O g -1 dry weight and survive the re-hydration process without permanent damage (Gechev et al., 2021). Three types of DT are known to be present in angiosperms, vegetative DT, seed DT and post- germination DT. Vegetative DT is seen in resurrection plants, and it remains throughout their life cycle. Seed-DT is acquired during seed maturation however lost during seed germination (Dekkers et al., 2015). Post-germination DT is the revival of DT during germination if seedlings get exposed to environmental stress, however post-germination DT remains within a time window (like 2-3 days after germination) and stress treatment given after this time window cannot induce DT (Maia et al., 2011). Understanding of DT is important as it can be used to build drought tolerance in plants and to build DT in recalcitrant (desiccation-intolerant) seeds of economically important crops, and it can also be applied to enhance the storage lives of biomaterials like somatic embryos, artificial seeds, germplasm, eukaryotic cells, blood cells, tissues, biomolecules or vaccines, etc. (Dekkers et al., 2015). Antioxidant activity is a crucial component of DT. Unique antioxidants may be involved under desiccation and subsequent rehydration (Veljovic-Jovanovic et al., 2008) however antioxidants are less studied under desiccation compared to other stresses in plants. Gamma-amino butyric acid (GABA) acts as a signaling molecule and activates antioxidant defense and GABA also has metabolic roles under stresses (Seifikalhor et al., 2019). Only a few reports have linked GABA with dehydration. In Arabidopsis thaliana, GABA hyperaccumulated in seeds during seed maturation (Fait et al., 2011). GABA accumulated in the embryo and endosperm of green coffee beans ( Coffea arabica L.) during drying (Kramer et al., 2010). GABA and proline enhanced in radish roots (daikon) ENVIRONMENTAL SCIENCE ARCHIVES ISSN: 2583-5092 Volume IV Issue 1, 2025 RESEARCH PAPER OPEN ACCESS Received: 2024/12/30 Accepted: 2025/01/25 Published: 2025/01/27