New results of Land Green Technology research - in the article "Impact of nano-nutri-priming and hydro-priming on Shiroudi (Oryza sativa) traits in different pH environments"
ABSTRACT
Nanoparticles (NPs) in agriculture present new opportunities to modify seed behavior and induce physiological, metabolic, and morphological changes, particularly through innovative seed priming methods like nano-nutri-priming (Nnp). This study compared Nnp and hydro-priming (Hp) techniques on Shiroudi rice (Oryza sativa) under varied pH conditions. The Nnp method, using a nutrient mixture of boron, molybdenum, and manganese, showed significant enhancements under neutral pH, increasing germination percentage by 7.7%, vigor index-2 by 37.5%, and dry matter accumulation by 16.6% compared to the control. However, in acidic and alkaline conditions, the efficacy of NPs was inhibited, possibly due to pH-induced suppression of NP activity. In contrast, hydro-primed Shiroudi grown in acidic pH exhibited notable improvements, with germination increasing by 15.4%, vigor index-1 by 25%, and dry matter accumulation by 30.4%. Notably, root fresh weight increased with Nnp regardless of pH, and root dry weight was enhanced under neutral and alkaline conditions. Stepwise multiple regression analysis identified shoot dry weight as a strong predictor of overall dry matter accumulation, with a highly significant positive correlation (R = 0.72**), highlighting its potential as a valuable indicator for plant growth and biomass accumulation.
Keywords: rice, seed priming techniques, nano nutrient mixture, pH levels, physiological response
INTRODUCTION
Half of the world's population relies on rice as a core component of their diet, providing up to 50% of their daily caloric intake, making it essential for global food security (Fahad et al., 2019; Muthayya et al., 2014). However, climate change over the past decade has significantly affected cereal crops, particularly rice, leading to challenges that contribute to global food shortages (Mazhar et al., 2022). Rising temperatures and an intensified hydrological cycle are impacting seed germination and plant development, with the ability of seeds to germinate quickly and establish vigorous seedlings being crucial for successful crop production (Eskandari, 2013). Ranmeechai et al. (2022) emphasize that seed germination and vigor are critical to enhancing seedling growth and ultimately crop yield.
Germination begins with the absorption of water by mature, dry seeds (imbibition) and concludes with the elongation of the embryonic axis, typically the radicle, which penetrates the seed coat (Rajjou et al., 2012). During this process, α-amylase plays a key role in starch degradation, initiating the breakdown of native starch granules into smaller glucose fragments, which are essential for energy production during germination (Kato-Noguchi and Macías, 2005; Mishra and Dubey, 2008). Increasing α-amylase activity is vital for enhancing plant growth, especially in carbohydrate metabolism (Mahakham et al., 2017). Furthermore, priming, or hardening, has been shown to influence enzyme activity, aiding in the mobilization of sugars and improving seedling vigor (Farooq et al., 2006a). Hydropriming, a cost-effective priming technique, enhances germination by facilitating water absorption and boosting energy-related metabolites, which induce physiological changes in organic compounds, sugar levels, and ion accumulation, resulting in improved germination and stress resistance (Alvarado et al., 1987; Ellouzi et al., 2023).
