Department of Horticultural engineering, Faculty of Agriculture and Natural Resources, Imam Khomeini International University. Qazvin, Iran.
10.22059/ijhst.2025.382831.929
Abstract
This study examines the effects of arbuscular mycorrhizal fungi (AMF) inoculation (with and without) and paclobutrazol foliar application (0 and 200 μg/mL) on the physiological and biochemical responses of Dracocephalum moldavica L. under varying water availability (100%, 75%, and 50% of field capacity). Key parameters assessed include plant growth, pigment content, antioxidant activity, secondary metabolites, and stress-related enzyme activities. Water deficiency significantly inhibited plant growth and reduced pigment levels while elevating oxidative stress markers, such as malondialdehyde (MDA) and electrolyte leakage (EL). In response to water stress, plants showed increased phenolic and flavonoid contents, indicative of an enhanced defense response. Total phenolic content (TPC) rose with increasing water stress, reaching a maximum of 47.35 GAEs/g extract at 75% field capacity (S2), compared to a minimum of 32.24 GAEs/g extract at 100% field capacity (S0). Mycorrhizal inoculation notably enhanced growth, chlorophyll content, phenolic and flavonoid levels, and antioxidant enzyme activities, while reducing oxidative stress markers, underscoring its role in promoting resilience under water stress. Mycorrhiza-inoculated plants (M1) showed a TPC of 43.00 GAEs/g extract, versus 36.01 GAEs/g in non-inoculated plants (M0). Paclobutrazol application induced a compact growth form with increased branching, enhanced chlorophyll content, and greater antioxidant activity. The combined application of AMF and paclobutrazol displayed synergistic effects, bolstering plant resilience to water stress through stabilized growth, pigment content, and antioxidant defenses. The interaction of water stress and mycorrhizal treatment produced the highest TPC (51.40 GAEs/g extract) under 75% field capacity with AMF treatment (S1M1).
Mafakheri, S. , Asghari, B. and Nasiri, R. (2026). Impact of Water Deficiency, Mycorrhiza Inoculation, and Paclobutrazol on Physiological and Biochemical Parameters in Dracocephalum moldavica L.. International Journal of Horticultural Science and Technology, 13(1), 173-192. doi: 10.22059/ijhst.2025.382831.929
MLA
Mafakheri, S. , , Asghari, B. , and Nasiri, R. . "Impact of Water Deficiency, Mycorrhiza Inoculation, and Paclobutrazol on Physiological and Biochemical Parameters in Dracocephalum moldavica L.", International Journal of Horticultural Science and Technology, 13, 1, 2026, 173-192. doi: 10.22059/ijhst.2025.382831.929
HARVARD
Mafakheri, S., Asghari, B., Nasiri, R. (2026). 'Impact of Water Deficiency, Mycorrhiza Inoculation, and Paclobutrazol on Physiological and Biochemical Parameters in Dracocephalum moldavica L.', International Journal of Horticultural Science and Technology, 13(1), pp. 173-192. doi: 10.22059/ijhst.2025.382831.929
CHICAGO
S. Mafakheri , B. Asghari and R. Nasiri, "Impact of Water Deficiency, Mycorrhiza Inoculation, and Paclobutrazol on Physiological and Biochemical Parameters in Dracocephalum moldavica L.," International Journal of Horticultural Science and Technology, 13 1 (2026): 173-192, doi: 10.22059/ijhst.2025.382831.929
VANCOUVER
Mafakheri, S., Asghari, B., Nasiri, R. Impact of Water Deficiency, Mycorrhiza Inoculation, and Paclobutrazol on Physiological and Biochemical Parameters in Dracocephalum moldavica L.. International Journal of Horticultural Science and Technology, 2026; 13(1): 173-192. doi: 10.22059/ijhst.2025.382831.929
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