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THE CROP DISEASES OF SIKKIM
HIMALAYAS |
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CROP: LARGE CARDAMOM
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Scientific Name |
Amomum subulatum
Roxb. |
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Local Name |
Elaichi/ Bara elaichi |
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Family |
Zingiberaceae Distribution
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State/World wide |
Sikkim, Darjeeling, Arunachal Pradesh,
Bhutan, Nepal
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Common Name of Disease:
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4.
RHIZOME ROT |
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Local Name of Disease |
-Adua Kuhiney Bimar |
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Causal Organism |
-Rhizoctonia solani Khun,
Pythium vexans de Barre and Fusarium
oxysporum. |
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Distribution of Disease in Sikkim
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-Present in all the four
districts of Sikkim irrespective of variety and
locality.
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Disease Incidence |
-Medium to High. |
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Site of Infection |
-Leaves, pseudostems , clumbs, rhizomes
and roots |
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Dissemination of the Disease |
-Through infected
planting materials, contaminated tools,
soil, seeds and contaminated
irrigation water. |
Symptoms
Chlorosis of older
leaves.Emerging heart leaf shows necrosis.
Splitting of the base of the
pseudostem.Brown to black discolouration of
the leaf sheath and also discolouration of
the vascular tissues. Roots get blackened
first followed by rotting and drying up of
the whole plants.In grown up seedlings, the
infection starts from collar region and
spreads into rhizome which first becomes
discoloured and subsequently decays.In grown
up plants, the pseudostems and rhizomes
become soft, ultimately resulting in the
death of the clump.Brownish discolouration
in the color region of the pseudostem
indicates infection of Rhizoctonia. Whereas
pinkish discolouration and softness of
pseudostem resulting in decay is the symptom
of Pythium infection.Sudden wilting of the
plant or leaf is the characteristic symptom
of the Fusarium wilt.The vascular
discolouration from brown to black
throughout the pseudostem. The roots show
blackening and the bark peeled off easily
resulting to drying up of the whole clump.
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Favourable environmental condition
for disease
Inadequate shades,
water stress condition, lack of phyto-sanitation.
Nutrient deficient plants are susceptible to
diseases of any kind. Weeds in the cardamom
field also act as alternate host for the
pathogen to persist.
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Mode of
Transmission
Pathogens are
primarily transmitted through infected
planting materials (suckers, seedlings).
Use of contaminated tools and
implements.
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Life cycle of
Organism
Rouging out the diseased clumps and burning
them to avoid spreading of the disease.
Maintaining 50% shade trees. Providing
irrigation during less rainfall season.
Nutrient management through application of
FYM.Maintain field sanitation weeding,
removing the old cut tillers and debris from
the field. Maintain proper spacing 150 cm
plant to plant.Soil application of
Trichoderma viridie or Trichoderma harzianum
(bio-control agent)can suppress the
pathogen.Soil drenching or spraying bacillus
subtilis mixed with cow urine diluted with
water in the ratio of 1:5:10 can also
suppress the pathogen.
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| Bioinformatics Sub- DISC, SSCS&T |
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