Combined Effect of Insufficient Watering, Moderate Cooling, and Organophosphorous Plant Growth Regulator on the Morphology and Functional Properties of Pea Seedling Mitochondria

Aims: In nature, plants are exposed to not one but several environmental factors. In this connection, the problem of studying the rearrangements of plant cell metabolism under exposure to several abiotic factors is of special importance. Various stresses lead to dysfunction of mitochondria that underlie the development of cell death and the whole organism. It is known that regulators of plant growth and development increase the resistance of plants to both biotic and abiotic stressors. One of such growth regulators is melaphen, a melamine salt of bis (hydroxymethyl) phosphinic acid. The aim of this work was investigation the effects of combined action of insufficient watering, moderate cooling to 10-14ºC and plant growth by regulator melaphen (melamine salt of bis(oxymethyl)-phosphinic acid) on the atomic force microscopy images of isolated mitochondria 5 day-old seedlings of pea (Pisum sativum L).
Place and Duration of Investigation: Emanuel Institute of Biochemical Physics Russian Academy of Sciences, Moscow, Russia and Timiryazev Institute of Plant Physiology Russian Academy of Sciences, Moscow, Russia, between June 2009 and October 2012.
Methodology: Functional state of mitochondria were researched by rate of mitochondria respiration, by the level of lipid peroxidation, the structural characteristics of mitochondrial membranes and by mitochondrial morphology, which was studied by method of atomic force microscopy.
Results: An atomic force microscopy (AFM) technique has revealed a statistically significant change in the shape of mitochondria (swelling mitochondria) exposed to insufficient watering and moderate cooling, which was associated with activation of lipid peroxidation in mitochondrial membranes and with disturbance of bioenergetics functions of these organelles. Treatment of pea seeds with 2x10-12 M solution melaphen prevents mitochondrial swelling and associated with that dysfunction of organelles
Conclusion: It was suggested that the effect of the drug on the morphology of mitochondria was associated with its antiradical and antioxidant properties.