Manganese sulfide nanoparticles (MnS NPs) enhance morpho-physiological traits, productivity and oil yield in linseed under field trial

The study was conducted to assess the effect of manganese sulfide (MnS) nanoparticles (NPs) on linseed (Linum usitatissimum L.) crop under field conditions. MnS NPs was applied in soil at the rate of 8 kg ha−1. Application of MnS NPs increased root and shoot length by 18.7 and 8.9%, respectively; and number branches and dry weight per plant 30.3 and 30.36%, respectively. Number of seed ball per plant, seeds per ball, and oil content raised by 52, 25.86, and 19.8%, respectively in MnS NPs treated plants as compared to control. Two folds increase in superoxide dismutase activity and 83.8% increase in peroxidase activity was observed in NPs treated plants as compared to control. Total phenolic content increased by 18.6% while 22.09% increase in total flavonoid content was observed in NPs treated plant shoots. Shoots of MnS NPs treated plants also showed 42.5% increase in DPPH radical scavenging activity. Total reducing potential and total antioxidant capacity also increased by 57% and 14.7%, respectively as compared to control. Atomic absorption spectroscopy showed increase in Mn accumulation in MnS NPs treated linseed plants followed by MnSO4 treated and control plants. Gas chromatography mass spectrometry analysis of oil extracted from linseed showed raise in the proportion of unsaturated fatty acids under MnS NPs treatment. FT-IR spectroscopy, 13C and 1H NMR confirmed these compositional shifts, thereby validating the GC-MS results. These findings indicate that MnS NPs can be applied as an efficient micronutrient delivery system to promote growth, antioxidant defense, yield, and oil content without disrupting the oil composition.