Flag smut of wheat

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Pathogen

:-

Symptoms

: Urocystis agropyri • Attacks the leaves and stems of wheat plants.

• The fungus produces grey-black lines of spores that run parallel to the leaf veins.

• Infected plants are often stunted and the flag leaf twisted. • Spores on infected leaves and straw are spread onto the grain and soil surface.

• Flag smut has both a soil and seed borne disease.

Flag smut

Control of flag s mut disease

• 

By resistant varieties

NP 165,WG 189,VL 426,HD 2117, HW161,HB 121, HB 113, etc.

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By seed treatment

• • Seed treated with sulpher or organo-mercurials.

Foliarflo-C, Maxiflo, Vitaflo C, Vitavax 200FF, Proguard Plus, Proleaf Plus, Rancona C , etc.

• •  Clean seeds should be used.

By crop rotation

Also effective in controlling this disease.

Foot rot disease :-(

Bakanae disease )

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Pathogen:-

Fusarium moniliforme

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Symptoms :-

• abnormal elongation of plants. • drying of leaves at late infection.

• Infected plants several inches taller than normal plants .

• Thin plants with yellowish green leaves and pale green flag leaves.

• infected seedlings with lesions on roots die which may die before or after transplanting .

Foot rot disease

Control:-

• 

By resistant varieties

Co-18,Co-22,ADT-8,PTB-7,G.E.B. 24, etc • • • 

By seed treatment

Clean seeds should be used.

Salt water can be used to separate lightweight, infected seeds from seed lots. Seed treatment using fungicides such as

thiram, thiophanate -methyl, or benomyl

is effective before planting.

Stem rot disease :-

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Pathogen :-

Sclerotium oryzae

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Symptoms:-

• Small, irregular black lesions on the outer leaf sheath near water level.

• Lesions expand as the disease advances • Infected stem rots.

• Visible numerous tiny white and black sclerotia and mycelium inside the infected culms • Infected culm lodges and caused unfilled panicles and chalky grain • Severe infection causes tiller death • The disease aggravates the plants to lodge

Stem rot disease

Stem rot disease control

• 

By resistant varieties

•  Basumati 3, Basumati 370,Mashkan 7,Mashkan 41,Bara 62 etc

By crop rotation

• Proved beneficial for disease control.



By proper manuring

• A balanced use of fertilizer with high

potash

and lime to increase soil pH reduces stem rot infection and increases yield.

• • 

By spraying

Chemicals such as

fentin hydroxide

sprayed at the mid-tillering stage.

Thiophanate-methyl

sprayed at the time of disease initiation can reduce stem rot incidence in the rice field.

The use of fungicides such as

Ferimzone and validamycin A

effectively against the fungus.

also show

• • • • • •  

Pathogen:-

Sheath blight:-

Rhizoctonia solani Kuhn Symptoms:-

Initial lesions are small, ovoid, greenish-gray and water-soaked.

develop near the water line in lowland fields.

Older lesions are ovoid with a grayish white center and light brown to dark brown margin.

Lesions may reach the uppermost leaf under favorable conditions.

Lesions may forming bigger lesions with irregular outline and may cause the death of the whole leaf.

Severely infected plants produced poorly filled or empty grains, especially those on the lower portion of the panicles

Control of Sheath blight:-

• •  •  • • 

plant spacing

plant spacing should be optimized.

Dense crop growth which favors the horizontal spread of the disease.

Sanitation

Removing of weeds, can help control sheath blight.

Pathogen attacks weeds which are commonly found in rice fields .

Spraying

Spraying infected plants with fungicides, such as

benomyl and iprodione, and antibiotics

, such as

validamycin and polyoxin

, is effective against the disease.

• 

Biological control Trichoderma & gliocladiumare used to control disease