RED ROT OF SUGARCANE

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  • The red rot is a very known disease in sugarcane.
  • Sugarcane is a major agricultural crop worldwide. India is the largest consumer and the second-largest producer of sugar and the production of sugarcane plays a vital role. But diseases affecting sugarcane are a major concern for the low yield.
  • It is also known as the cancer of sugarcane.
  • It is caused by  Colletotrichum falcatum Went.
  • It was recognised as a disease in Java by Went in 1893
RED ROT OF SUGARCANE
RED ROT OF SUGARCANE

Organism Involved

Red rot of sugarcane is caused by  Colletotrichum falcatum Went

Systematic Position

Division:                Eumycota
Subdivision:          Deuteromycotina
Class:                       Coelomycetes
Order:                      Melanconiales
Family:                    Melanconiaceae
Genus:                     Colletotrichum
Species:                   falcatum
  • The common name of the disease is called Red Smut
  • C. falcatum is a  facultative saprophyte.
  • It is a toxic producing fungi.
  • It’s sexual stage is known as Glomerella. tucumanensis is responsible for the survival of the fungus on decaying leaves and formation of new virulent pathological diseases.

Distribution

  • The major sugarcane producing countries are Brazil, India, United States of America , Australia, Thailand, Pakistan, China and Mexico,

Mode of Infection

  • The pathogen mainly infects canes through nodes and the main portal of entry are leaf scar, growth ring, root primordia and buds.
  • The disease attacks the sugarcane at the stalks, stubble rhizomes, and leaf midrib. It may even extend to leaf-blade and leaf-sheath tissues and is capable of infecting sugarcane roots.

Symptoms of Red Rot Of Sugarcane

  • Red rot can only be observed when it has been completely rotted in the interior and lose its natural bright colour and become dull.
  • Plants can be seen yellowing, shrivelling, and dying of the upper leaves.
  • The disease can be recognized by the longitudinal reddening of the normally white or
    yellowish-white internal tissues of the internode
  • The lesions on the leaf midribs can be seen as dark reddish areas which may elongate and reach the entire leaf.
  • The young lesions are blood red in colour with darker margins.
  • The centers start fading and become straw-coloured with age, and when fructification of the fungus begins, the lesions are covered with black powdery masses of conidia.

Favourable conditions for the cause of the disease

  • It was considered that bad cultivation and poor drainage favour the cause of the disease
  • Environmental conditions in subtropical countries favour the disease.
  • Mean temperature range of 29.4 to 31°C
  • High atmospheric humidity

Losses Caused

  • The disease causes a stiff drop by reducing the crop stands and by reducing the sucrose content of the cane juice.
  • Additional to the sucrose reduction in internodes, the joints above the diseased positions were also affected.
  • Decreased juice extraction, percentage of solids and sucrose in the juice, purity and chemical changes were observed.
RED ROT OF SUGARCANE
Disease Cycle of Red Rot Of Sugarcane

 

Disease Control

  • The control of the diseases depends upon weather conditions, genotypes, presence of virulent
    pathogen and time for disease development.
  • It is impossible to control the disease once it appears on the field.
  • The direct focus can be in prophylactic measures to reduce pathogen build up in the field
  • Integrated Disease Management (IDM) can be followed.
  • Resistance varieties can be grown which is an efficient alternative against such huge losses.
  • Good cultural practices, using disease-free planting materials, physical, biologic and chemical control may aid to the control of diseases
  • Sustainable alternative including Bio-control agents can be used for the control.

References

  1. https://www.researchgate.net/publication/343896734_Current_and_Prospective_Strategies_on_Detecting_and_Managing_Colletotrichumfalcatum_Causing_Red_Rot_of_Sugarcane
  2. https://naldc.nal.usda.gov/download/CAT86200636/PDF
  3. https://www.researchgate.net/publication/333194052_A_Review_on_Red_Rot_The_Cancer_of_Sugarcane#pf2