The Effects of Endophytic Fungus Piriformospora indica on Morphophysiological Traits of Pyrus Rootstock cv. Pyrodvarf under Salinity Stress Conditions

The pear is one of the most important fruit trees in temperate regions and is salt-sensitive trees. Studies have shown that the use of Piriformospora indica as an endophytic fungus reduces the adverse effects of salinity stress on plants and improves morphophysiological traits.

In the present study, the experiment was performed as a factorial completely randomized design with 5 replications on the pyrus rootstock CV Pyrodvarf in pot culture experiment. The first factor includes two levels of P. indica fungus (inoculation and non-inoculation) and the second factor is four salinity levels of soil (1.7, 3, 4.5 and 6 dS.m-1) using sodium chloride. After inoculation with the fungus, the salinity levels were applied to the plants.

The results showed that the interaction effect of salinity × fungi on morphophysiological characteristics, total chlorophyll content (P <0.05), branch diameter growth, electrolyte leakage, proline, soluble sugars, peroxidase and polyphenol oxidase enzymes and root colonization percentage (P <0.01) were significant. At the highest salinity levels (6 dS/m), fungal inoculation caused an increase in surface-to-root dry weight ratio (38.81%), branch diameter growth (31.14%), total chlorophyll (27.72%), peroxidase (100%), polyphenol oxidase (62.5%) and root colonization percentage (100%) and decrease in electrolyte leakage rate (19.34%), proline (10.34%) and soluble sugars (8.77%) ) compared to non-inoculated control plants.

In general, the results of this study showed that the coexistence of P. indica can modulate the destructive effects of salinity on this pear cultivar.