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Post harvest diseases of bhendi Alternaria rot - Alternaria alternata Rhizoctonia rot - Rhizoctonia solani

Post harvest diseases of bhendi Alternaria rot - Alternaria alternata Rhizoctonia rot - Rhizoctonia solani

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Page 1: Post harvest diseases of bhendi Alternaria rot - Alternaria alternata Rhizoctonia rot - Rhizoctonia solani

Post harvest diseases of bhendi

Alternaria rot - Alternaria alternata Rhizoctonia rot - Rhizoctonia solani

Page 2: Post harvest diseases of bhendi Alternaria rot - Alternaria alternata Rhizoctonia rot - Rhizoctonia solani

Alternaria rotAlternaria alternata

Dark grey, slightly sunken irregular lesion, developing lengthwise

Grey cottony mycelial mat bearing conidia appeared on the surface of developing lesions

When diseased pod cut transversally – blackened necrotic tissues

Page 3: Post harvest diseases of bhendi Alternaria rot - Alternaria alternata Rhizoctonia rot - Rhizoctonia solani

Fungus Conidiophores - simple straight or curved, sometimes

branched Yellow brown to medium golden brown colour Conidia - transverse and longitudinal septa, pale to dark brown

in colour, produced in short chains

Page 4: Post harvest diseases of bhendi Alternaria rot - Alternaria alternata Rhizoctonia rot - Rhizoctonia solani

Rhizoctonia rot Rhizoctonia solani

Pod - greenish color turning brown, and the infected tissues fully covered with mycelia

Internally, immature seeds and placenta were infected and the diseased tissues were light brown to black

Externally, mycelia tend to be fluffy and lighter in color, forming a large number of dark sclerotia on the fruit surface

A. Pods showing distinct degrees of rotting

B. Rotting of placenta tissues and immature seeds

Page 5: Post harvest diseases of bhendi Alternaria rot - Alternaria alternata Rhizoctonia rot - Rhizoctonia solani

Fungus Produces pycnidia and sclerotia Pycnidiospores - hyaline, single celled, ovate to ellipsoid

Mode of spread and survival R. solani overwinters in soils as mycelia on plant debris and

as dark brown sclerotia that remain in soil for long periods

Control Plant debris from previous crops should be removed before

planting

Quintozene – sprayed in the soil before sowing-effective control

Page 6: Post harvest diseases of bhendi Alternaria rot - Alternaria alternata Rhizoctonia rot - Rhizoctonia solani

Phoma canker (Phoma exigua) Water soaked lesion appear on fruits Black spots with irregular margin Black area - pycnidial formation 80-90% fruit loss post harvest rot of okra pods rhizoctonia solani

in brazil Completely rotted, the pod's typical greenish color turning brown

and the infected tissues fully covered with mycelia Internally, immature seeds and placenta infected Diseased tissues were light brown to black . Externally, mycelia tend to be fluffy and lighter in color, forming

a large number of dark sclerotia on the fruit surface