Glomerella graminicola

(1923) Vermicularia melicae Fuckel Glomerella graminicola is an economically important crop parasite affecting both wheat and maize where it causes the plant disease Anthracnose Leaf Blight.

[2] Corn anthracnose leaf blight is the most common stalk disease in maize and occurs most frequently in reduced-till or no-till fields.

[6] The mid-season symptoms appear several weeks after corn produces tassels, when there will be a top die-back if the infection has spread throughout many parts of the plant.

Growth on potato dextrose agar is: In the spring, fruiting structures (acervuli) form from corn residue and produce banana-shaped[8] spores (conidia) that are dispersed by wind blown raindrops and splashing.

[9] Overwintering on corn residue serves as a vital source of primary inoculum for the leaf blight phase in the spring.

[13] A specific temperature range is required in order for the pathogen to successfully infect the host plant, between 25 and 30 °C (77 and 86 °F).

Continuous plantings of the same host without introducing crop rotation and no-till fields will favor persistence of the pathogen between growing seasons.

[15] Since C. graminicola is found to survive on corn residue, specifically on the soil surface, one of the most effective methods of control is a one-year minimum of crop rotation to reduce anthracnose leaf blight.

[16] There are cultural practices that can be taken to disrupt the primary inoculum phase and conidial spore infection of the host plant, and these include using hybrid cultivars resistant to the pathogen[15] and keeping the host plants healthy and controlling other pests to keep them resilient to infection.

[17] There is also a cultural practice that disrupts the saprophytic stage of the pathogen, and this involves plowing the leftover corn residue deep into the soil and then using a one-year crop rotation away from the same host plant that was just used in that field.

[18] Estimates on yield grain losses from anthracnose leaf blight and stalk rot range from zero to over 40%.

Once conidia germinate on corn leaves, a germ tube differentiates and develops into an appresoria and allows C. graminicola to penetrate epidermal cells.

This builds up an incredible amount of turgor pressure which the fungus then uses to push a hyphae through the corn cell wall.

Between 48–72 hours after infection, C. graminicola shifted from biotrophic growth to nectrotrophy (lesions appear).