نقش كاربرد برگي نانو ذرات سيليس و تلقيح قارچ‌هاي آربسكولار مايكوريزا بر صفات فيزيولوژيكي، مورفولوژيكي و ويژگي‌هاي عملكرد گل محمدي (Rosa damascena)

The results demonstrated that the combined application of AMF an‎d 40 mg L⁻¹ silica nanoparticles significantly enhanced vegetative growth, increasing stem length an‎d stem diameter by 19% an‎d 58%, respectively, compared with the control. In addition, the integrated treatment markedly increased the activities of antioxidant enzymes, including catalase (21%) an‎d ascorbate peroxidase (74%), as well as total leaf chlorophyll content (47%) an‎d the chlorophyll index (48%). Furthermore, this treatment improved leaf water-use efficiency by 41%, performance index by 68%, an‎d the normalized difference vegetation index (NDVI) by 31%, while significantly reducing leaf temperature (19%), malondialdehyde (35%), hydrogen peroxide (41%), an‎d electrolyte leakage (24%) relative to the control. Regarding leaf mineral composition, the combined treatment increased magnesium, iron, an‎d silicon concentrations by 74%, 73%, an‎d 58%, respectively, while reducing nickel an‎d mercury accumulation by 36% an‎d 32%, respectively. The reduction in toxic element accumulation without disrupting the balance of essential nutrients represents an important outcome of this study for the safe production of medicinal plants. Moreover, the integrated application of AMF an‎d silica nanoparticles reduced aphid an‎d mite populations by 57% (11 May) an‎d 58% (31 June), respectively, compared with the control. These findings may be attributed to improved plant nutritional status, enhanced synthesis of defense-related metabolites, an‎d reinforcement of the structural integrity of plant tissues. Analysis of essential oil composition revealed that the combined treatment increased the relative abundance of linalool, rose oxide, citronellol, an‎d geraniol, suggesting activation of the biosynthetic pathway of oxygenated monoterpenes. Characterization of floral volatile compounds using the SPME-Arrow technique showed that 2-phenylethyl alcohol accounted for 81–86% of the total volatile profile. Furthermore, the combined application of AMF an‎d 20 mg L⁻¹ silica nanoparticles in genotype C193 increased linalool by 56%, geraniol by 63.1%, an‎d rose oxide by more than threefold compared with the control, whereas the higher concentration of silica nanoparticles resulted in a relative reduction in aldehydes an‎d phenylethyl derivatives. The biostimulant combination also had an important effect on pest suppression. At the peak of pest incidence, 40 mg/L silicon nanoparticles without mycorrhiza caused a 98% reduction in mite populations compared with the control. For aphids, a 70% reduction was observed at the same silicon level when mycorrhiza was present. These findings suggest that the treatments may improve indirect defense mechanisms, possibly through better nutrition, enhanced structural resistance, an‎d increased production of protective metabolites.

علي نيكبخت , مهدي رحيم ملك

جهانگير خواجه علي , مجيد طالبي

مهديه غلامي , محمدعلي حاج عباسي جورتاني , سعيد ريزي