Potential effect of phyto-synthesized silver nanoparticles using Cotula cinerea Del Raw extract on salt tolerance of wheat seeds (Triticum durum desf, Boussellam variety) germination.

This study uncovers a novel and environmentally sustainable method for synthesizing silver nanoparticles (AgNPs) utilizing Cotula cinerea extract, a plant that has not been previously explored for nanoparticle (NP) fabrication. The study is to evaluate the efficacy of a nano primer in mitigating salt stress in durum wheat (Triticum durum Desf Boussalem variety). AgNPs extract spectra showed a sharp peak at 445.91 nm in UV-vis while X-ray diffraction (XRD) reflected the patterns of the face-centred cubic (fcc) and crystalline structure and the scanning electron microscopy (SEM) study revealed that the NPs have an almost spherical and somewhat cuboidal morphology, with dimensions under 20 nm. The transmission electron microscopy (TEM) study revealed an average particle size distribution of 15.128 nm, largely exhibiting a spherical morphology. The hydrodynamic diameter measured (DLS) indicated a particle size of 351.6 nm, which is much larger. Seeds were treated with 0, 20, 40, and 80 mg L-1 of AgNPs and exposed to 0 and 150 mM NaCl. At a concentration of 40 mg/L of AgNPs, germinability attained 90% under saline conditions, in contrast to 70% for the control group, while root length (RL) exhibited an 86% increase, measuring 7.28 cm compared to 3.9 cm in the control group. At a concentration of 20 mg/L of AgNPs, root fresh weight (RFW) increases from 0.04 to 0.06 g in saline conditions and from 0.06 to 0.09 g in the absence of salt. The control group exhibited a root number (RN) of 3.67, while plants treated with 20 mg/L demonstrated a significant increase to 5.54. Additionally, shoot length (SL) under saline stress reached 11.12 cm, compared to 8.26 cm in saline conditions. These findings underscore the potential of green synthesised AgNPs as an effective approach to enhance the salt tolerance of durum wheat and promote sustainable agriculture in saline conditions.