its common name because of the geographical area where it is most prevalent, the cotton-growing region of Texas. Texas, an area located in the southern half of the United States, receives an annual rainfall between 127 cms and less than 25 cms. Researchers collected data on Texas root rot virulence over 13 years at the Blackland Research Center using cotton plants infected with Texas root rot and found that virulence correlates somewhat with precipitation in the range of 36–100 cm of rainfall. Higher virulence of Texas root rot was observed after large precipitation events. These experimental findings support the conclusion that Texas root rot preferentially develops in wet over dry soil conditions. The same study also found that virulence of Texas root rot develops inversely to air temperatures over 93 degrees Fahrenheit. The symptoms of Texas root rot are most severe during hot summers when air temperature increases the average soil temperature over 80 degrees Fahrenheit. The elevation in temperatures produces Texas root rot’s most severe symptoms: wilting and bronze colored leaves. The pathogen is only active in the summer months when the high average temperatures can heat the soil microclimate one foot deep over 80 degrees Fahrenheit. Disease cycle The disease overwinters as sclerotia or as mycelium on dead plant tissue. In spring to early summer, the germination phase begins with hyphae growth and root colonization. In middle and late summer, the disease reaches its infectious stage when associated symptoms are observed. The pathogen penetrates the host and colonize plant root tissue causing a root rot. This results in the first symptoms of the disease manifested by chlorotic leaves and eventually wilting. Root rot disease rings enlarge, and the field can be categorized into three zones based upon plant status: asymptomatic, disease front and survivor. The pathogen disseminates by infecting neighboring plants, with infected plant tissue serving as a secondary inoculum and further spreading the disease. In situations of high moisture, conidia are produced on spore mats but their role in dispersal is unknown since conidia rarely germinate. Phymatotrichopsis omnivora form several kinds of differentiated hyphae. Initially, hyphae emerge from sclerotia overwintering in soil. Sclerotia are the primary inoculum in affected fields. The emerging hyphae either infects the host root or form mycelial strands with a differentiated rind. Upon contact with host roots, P. omnivora forms a mycelial mantle on the root's surface. This leads to necrosis of epidermis