Involvement of Nitric Oxide in Biochemical and Physiological Response of Potato Seedling Under Cold Stress

Abstract

Cold temperatures harm tropical crops, but understanding how molecular signals help plants cope could aid in climate change adaptation. This study tested if sodium nitroprusside (SNP), a nitric oxide (NO) donor, could improve potato tolerance to cold. Potato seedlings, treated or non-treated (0.5 mM) with SNP, were exposed to cold stress (0 and ‒2 °C) for 6 h. The study was conducted in a completely randomized design, incorporating three factors in three replications. Results showed that cold stress reduced physiological and biochemical parameters in all seedlings, but less so in those treated with SNP. SNP treatment boosted physio-biochemical activity and increased levels of soluble sugars and enzymatic and non-enzymatic antioxidants. Seedlings treated with SNP and exposed to cold stress had lower levels of H₂O₂ and malondialdehyde, suggesting that NO may alleviate the harmful effects of cold. The analysis conducted using PCA demonstrated correlations between variables and treatment groups. Notably, the first two principal components (PC1 and PC2) accounted for 77.6% and 78.1% of total variance, respectively, under both 0 and − 2 °C temperatures. Under temperatures below 0 °C, the results of the factor analysis (FA) revealed that PC1 exhibited the highest distribution of data, containing the most prominent variation in Squared cosine values (SCV) values at 0.79. Among the variables, Electrolyte leakage (EL) had the best representation in PC1, with the corresponding maximum SCV values at 0.78 under − 2 °C. This result highlights the potential use of SNP in manipulating cold tolerance in potato plants.