AM Fungi and Abiotic Stress

AM Fungi and Abiotic Stress

a) Drought (Extreme dryness)

·      Drought stress affects plant life in many ways. Shortage of water to roots reduces rate of Transpiration as well as induces Oxidative stress.

·       Drought stress imparts deleterious effects on plant growth by affecting

ü  Enzyme activity

ü  Ion uptake

ü  Nutrient assimilation

·     Plant tolerance to drought could be primarily due to a large volume of soil explored by roots and the extra-radical hyphae of the fungi.

·       Symbiotic relationship of various plants with AM Fungi ultimately improves

ü  Root size and efficiency,

ü  Leaf area index

ü  Leaf water relations

ü  Biomass

ü  Gas exchange

ü  Osmotic adjustment

ü  Stomatal regulation and conductance

ü  Transpiration rate

ü  Accumulation of proline

ü  Glutathione level 

b) Salinity

·    Salinity is widely known that the soil salinization is an increasing environmental problem posing a severe threat to global food security.

·     Salinity stress is known to suppress growth of plants by affecting the vegetative development and net assimilation rate resulting in reduced yield productivity.

·   AM Fungi significantly alleviated the deleterious effects on photosynthesis under salinity stress. Mycorrhizal inoculation improves

ü  Photosynthetic rate

ü  Gas exchange traits

ü  Chlorophyll content

ü  Water use efficiency

ü  Leaf area index

ü  Fresh and dry biomass

ü  Synthesis of Jasmonic acid and Salicylic acid

ü  Nutrient uptake

c) Low Temperature and High Temperature

·     As soil temperatures increase, plant community reactions may be dependent on AM Fungal interactions for sustainable yield and production.

·       Heat stress significantly affects plant growth and development by imparting

ü  Loss of plant vigor

ü  Inhibition of Seed germination

ü  Retarded growth rate

ü  Decreased biomass production

ü  Wilting and burning of leaves and reproductive organs

ü  Abscission and senescence of leaves

ü  Damage as well as discoloration of fruit

ü  Reduction in yield and cell death

ü  Enhanced oxidative stress.

·      AM Fungi can increase plant tolerance to cold stress. Moreover, a majority of reports state that various plants inoculated with AM Fungal at low temperature grow better than non-AM Fungal inoculated plants.

·    AM Fungi also can retain moisture in the host plant, increase plant secondary metabolites leading to strengthen plant immune system, and increase protein content for supporting the plants to combat cold stress conditions.

·       During cold stress, AM Fungi inoculated plants showed an enhanced

ü  Water conservation capacity

ü  Gas exchange potential

ü  Osmotic adjustment

ü  Synthesis of chlorophyll

ü  Significant improvement in the concentrations of various metabolites