4 Major diseases of wheat: symptoms, biological features of pathogens, distribution, and harmfulness


Researchers from the CIMMYT international center have identified that wheat is susceptible to a variety of pathogens, including 25 fungal diseases, 3 bacterial infections, 1 viral disease, 3 nematode-related diseases, 4 physiological and genetic disorders, and 8 conditions linked to deficiencies in mineral nutrients or other abiotic factors. Although the pathogens that affect both winter and spring wheat are generally similar, there are occasional differences in specific instances. Wheat is frequently affected by four different forms of smut, three types of rust, powdery mildew, septoria leaf blotch, and helminthosporium leaf lesions, along with a range of root rot conditions. Additionally, the crop is vulnerable to bacterial infections, yellow mold or slime mold diseases, basal disorders, and a number of viral infections (Prescott et all., 1986; Koishybaev, 2002; Dubeiller, Singh et all, 2014).

 

Table 2 - Disease spectrum of spring wheat and their pathogens, affected plant organs

Disease

Pathogen(s)

Affected plant organs

Loose smut

Ustilago tritici

entire ear

Common bunt (Stinking smut)

Tilletia caries, T. levis

spikelets

Ergot

Сlaviceps purpurea

grains

Stem rust

Puccinia graminis f. sp. tritici

stems, glumes, leaves

Leaf rust (Brown rust)

Puccinia recondita f. sp. tritici

leaves

Powdery mildew

Erysiphe graminis

leaves, stems, glumes

Septoria leaf blotch

Stagonospora nodorum

Septoria tritici

leaves, stems, glumes

Tan spot (Yellow leaf spot)

Drechslera tritici repentis

leaves, stems

Root rot - Helminthosporium type

Bipolaris sorokiniana (syn.

Helminthosporium sativum)

primary and secondary roots, stem internodes

Root rot - Fusarium type

Fusarium spp.

primary and secondary roots, stem internodes

Black point

Alternaria alternata,

B. sorokiniana

grain, seeds

Wheat streak mosaic

Triticum virus

leaves

Mucilaginous or yellow bacterial blight

Rathayibacter tritici

leaves

Basal bacterial disease

Pseudomonas syringae pv.

atrofaciens

leaves