Fully developed lesions typically have a sooty appearance during humid weather, as a result of spore (conidia) formation.
As the disease progresses, the lesions grow together and create large areas of dead leaf tissue.
Thirty six maize genotypes comprising composites, hybrids, inbreds line were screened against Exserohilum turcicum under artificially inoculated field conditions and maximum disease intensity was recorded in Super 1 (55.87) followed by C-8 (55.80).
However, minimum disease intensity was observed in Vivek maize hybrid (3.80%).
With its characteristic cigar-shaped lesions, this disease can cause significant yield loss in susceptible corn hybrids.
These lesions may first appear as narrow, tan streaks that run parallel to the leaf veins.On the basis of prevalence of Turcicum blight of maize, the districts were categorized as low (Kathua), medium (Samba and Jammu) and high disease (Udhampur) districts.The isolates selected from different locations showed variation in colony growth characteristics exibiting irregular/ profuse/ sparse or cottony growth.Survey for Turcicum blight of maize conducted during 20 in Jammu division revealed that maximum disease intensity was observed in Udhampur district with the range of 37.30- 41.93% followed by Samba ranging from 29.28-32.07% disease intensity.However, minimum disease was observed in Kathua district (24.71-25.76%).Grain yields of different maize genotypes differed significantly in protected and unprotected treatments.It was observed that the loss in grain yield varied from 18.32 to 60.52% depending upon the disease severity in different genotypes.The shape of spore observed were curved, elongated, spindle and the pigmentation was red, grey and black. Et12 showed excellent growth on PDA while on V8 medium the isolates showed fair growth.The pathogenic reaction of different isolates were categorized as per the scale and the isolates Et1, Et2 and Et4 recorded a score of 3.34 while ET3, ET5 and Et8 scored 2.67.Lesions on products containing resistance genes may appear as long, chlorotic, streaks, which can be mistaken for Stewart’s wilt or Goss's wilt. turcicum lives and reproduces in an asexual phase with a relatively simple life cycle.In temperate regions, the fungus overwinters mycelia, conidia, and chlamydospores in the infected corn debris.