DRY ROT:GINGER

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Common Name of Disease:	3. DRY ROT
Local Name of Disease	-

Causal Organism

-Fusarium oxysporum and Pratylenchus coffeae

Distribution of Disease in Sikkim

-Disease incidence is more in dry areas of South and West Sikkim and also in some areas of East and North Sikkim.

Disease Incidence

-Moderate

Site of Infection

- Roots are affected first followed by rhizome. However, symptom could be seen on the leaves on the standing crop (marginal yellowing of leaves ).

Dissemination of the Disease

- It is a seed-borne and soil borne disease.

Symptoms
The affected plants appear stunted and exhibit varying degree of foliar yellowing. The affected rhizomes and roots show brownish lesions which later merge. In advance stages the rhizomes when cut show a brownish ring and is mainly restricted to cortical region. The pseudostems of dry rot affected plant do not come off easily with a gentle pull in contrast to soft rot. The affected rhizomes are often shrunken and dry and are not marketable. Both nematode (Pratylenchus) and fungus (Fusarium sp.) are found associated in diseased rhizome..

Favourable environmental condition for disease
Water stagnation in the field during rainy season.Hot and humid weather condition favours the disease incidence. Injury caused to the rhizome during mau extraction makes the plant susceptible to the disease.

Mode of Transmission

Disease is transmitted to a healthy plot through infected planting materials. It is also a soil borne disease.

Life cycle of Organism
Plant Protection Measures: Seed should be selected from a diseased free source. Seed rhizomes should be treated with hot water at 51 degree centigrade for 10 minutes and shade dry before sowing in the field. Hot water treatment was found effective against dry rot caused by nematode. Crop rotation of 3-4 years should be followed to avoid disease incidence.Planting should be done on raised bed with proper drainage. Thick mulching should be provided to check weed growth and to conserve moisture. FYM should be well decomposed to avoid white grub infestation.

Brief history of the disease
The disease intensities augmented through years due to inadequate knowledge on their nature, lack of quality planting material and improper management practices.