One of the most harmful seed and soil borne pathogens, Macrophomina phaseolina is a fungus that infects nearly 500 plant species in more than 100 families.

[2] The failure to correctly detect and identify M. phaseolina using conventional culture-based morphological techniques has led scientists to develop nucleic acid-based molecular approaches, such as highly sensitive and specific polymerase chain reaction-based methods.

[4][5] Researchers have also recently created species-specific oligonucleotide primers[6] and digoxigenin-labeled probes[6] in hopes of better identifying and detecting M.

[5] The pathogen M. phaseolina affects the fibrovascular system of the roots and basal internodes of its host, impeding the transport of water and nutrients to the upper parts of the plant.

[7] As a result, progressive wilting, premature dying, loss of vigor, and reduced yield are characteristic symptoms of M. phaseolina infection.

[8] When the epidermis is removed, small and black microsclerotia (a sign of the disease) may be so numerous that they give a greyish-black tint to the plant tissue.

[8] In addition, reddish-brown discoloration and black streaks can form in the pith and vascular tissues of the root and stem.

The M. phaseolina fungus has aggregates of hyphal cells, which form microsclerotia within the taproots and stems of the host plants.

[3] Macrophomina phaseolina is a heat- and drought-favoring disease, producing large quantities of microsclerotia under relatively low water potentials and relatively high temperatures.