Biochemical responses of mycorrhizal-inoculated Lamiaceae (Lavender, Rosemary and Thyme) plants to drought: a field study

Abstract

Mycorrhizal symbiosis may help plants to compensate the water deficit-induced macronutrients, secondary metabolites and osmotic adjustments as the basis of crop production. The present investigation was undertaken to evaluate the physiological responses of the lavender (Lavandula officinalis L.), rosemary (Rosmarinus officinalis L.) and thyme (Thymus vulgaris) host plants to inoculation with mycorrhizal fungi (Funnelliformis mosseae, Rhizophagus irregularis compared with non-inoculated control treatment) in different irrigation levels (irrigation at 75% field capacity, 50% field capacity and rainfed). The 2-year (2015-2016) factorial experiment was conducted based on a randomized complete block design with three replications at Urmia University. The results showed that the stress treatments promoted the generation of osmotic adjustment (total soluble sugars and proline) in non-inoculated plants more than plants inoculated with fungi species. Nutrient (nitrogen, phosphorous and potassium) concentrations and leaf chlorophyll, reduced by water-limiting irrigation, were enhanced with mycorrhizal inoculation. Colonized plants were better adapted and had greater relative water content under stressful conditions due to higher absorption sites for water and nutrients. Also, stress treatments stimulated the phenylalanine ammonia-lyase, DPPH radical-scavenging activity and, the total phenolic and flavonoids content in non-inoculated plants more than that inoculated with two fungi species.

Influence of Water Regime Treatments on Growth of Rosmarinus Officinalis L. Plant

“…The aforementioned results are in conformity with those reported by Mohammadzadeh and Pirzad (2020) on (Lavandula officinalis L.), rosemary (Rosmarinus officinalis L.) and thyme (Thymus vulgaris L.).…”

Effect of water deficit on growth and concentration of secondary metabolites of Thymus vulgaris

“…The average SPAD values of the treatments are shown in Table 3. In another experiment on garden thyme, it was found that water deficiency had a negative effect on the chlorophyll content of the leaves (Mohammadzadeh, Pirzad, 2020); however, it has not been manifested obviously in our experiment. Nevertheless, some authors have found opposite reactions, as the chlorophyll content increases with the increased drought stress in garden thyme (Ashrafi et al, 2018); however, in basil, the chlorophyll content decreased with the reduced soil water content (Damalas, 2019).…”

Arbuscular mycorrhizal fungi increase crop yields by improving biomass under rainfed condition: a meta-analysis

“…Similarly, Zhang et al (2019a) also concluded that AMF inoculation in field led to 16% increase on cereal yield, which is the same tendency to our study. Numerous studies have confirmed that the dependency of host plant on AMF was higher in stress environments than in no-stress environments ( Latef et al, 2016 ; Hu et al, 2017 ; Mohammadzadeh & Pirzad, 2021 ). Furthermore, There are differences between grain crops and non-grain crops by AMF, which probably because the positive effect of AMF on yield depends on the plant species ( Tarraf et al, 2015 ).…”