Leaf/ Brown rust1. Leaf/ Brown rust:
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C. O. Puccinia recondia Rob. Ex. Desm f. sp. Tritici
Symptoms:
• Minute, round sori, irregulary distributed on the leaves
• Rarely on the leaf sheath or stem
• The orange sori turn brown with maturity
• In advance stage, telial stage formed on the same pustule which are small. Oval to linear, black
Management:
• Grow resistant variety viz. GW-496, GW- 273, Gw-322, GW-11, GW-1139
Stem/ black rust
2. Stem/ black rust:
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C. O. Puccinia graminis f. sp. tritici (Pers.) Eriks and Henn
Symptoms:
• Initially flecking leaves, leaf sheaths, callus and floral structure
• Uredosori develop as oblong, reddish, brown pustules frequently merging into one another
• On brusting of pustules, expose a mass of brown uredospores
• In later stage, telial stage formed and cause linear patches of black lesions
• Affected spikes gives shriveled grains or no grains
Management:
• Grow resistant variety viz. GW-496, GW- 273, Gw-322, GW-11, GW-1139
Yellow/ stripe rust3. Yellow/ stripe rust:
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C. O.: Puccinia striiformis West
Symptoms:
• Uredosori appears as bright yellow pustules chiefly on the leaves
• On severe infection, pustules found on the leaf sheath, stem, spikelets and glumes
• Sori are elongated and are arranged in linear raws between the veins of the leaf
• Teleasori more abundant on the leaf sheath than on the lea blade
Management:
• Grow resistant variety viz. GW-496, GW- 273, Gw-322, GW-11, GW-1139
Loose smut4.Loose smut:
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C. O.: Ustilago nuda var. tritici Schaf
Symptoms:
• Disease manifests itself only when the ears emerge from the boot leaf usually a few days earlier than healthy ons
• Usually all spikelets are affected
• Spikelets transformed into a mass of black powdery spores
• Black mass of spores is blown off by wind, leaving behind only the central rachis
Management:
• Use the seeds of disease free areas
• Treat the seeds with carboxin or oxycarboxin 2g/kg seed
• Rouging of infected plants reducing the disease spread
Karnal bunt
Karnal bunt5. Karnal bunt:
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C. O.: Neovossia indica (Mitra) Mundk
Symptoms:
• No symptoms until spike emerges
• Infection confined to a few grain in the spike and arrangement is irregular
• As the grain mature, the outer glumes spread out and the inner glumes expand, exposing the bunted grains
• Black masses of spore are exposed, resulting in the rotten fish odor because of Trimethyl amine on brusting of bunt balls
Management:
• Grow resistant variety
• Use the seeds of disease free areas for sowing
Black point
6.Black point:
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C. O.: Alternaria triticina
Symptoms
• Bold seeded varieties are most susceptible
• Blacking on the embroynal end of the grain
• On severity, spread grains and visible after threshing
• Not affect the yield but reduce market value
Management:
• Spray mancozeb @ 0.025% or chlorothionil @ 0.2% at the hard dough stage to minimize the disease in bold seeded varieties
Leaf blight/ Blotch
7. Leaf blight/ Blotch:
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a. Alternaria blight
C. O.: Alternaria triticina Prasada and Prabhu
Symptoms:
• Distinct reddish brown localized oval spots on leaves
• Later enlarge and become irregular with blight yellow margin
• Several spots may coalesce and blightening the leaf
b. Speckled leaf blotch
C. O.: septoria tritici Rob and Desm.
Symptoms:
• Disease appears on leaf blade and sheath
• Initially circular yellowish mottled spots, elongated into reddish brown spots, dotted with black pycnidia
• Heavy infected young leaves dry up prematurely
c. Drechslera (Helminthosporium) leaf spot
C. O.: Drechslera sorokiniana
Symptoms:
• Yellowish to oblong spots appears mostly on leaf and sheath at seedling stage which turn dark brown
• Straw coloured patches are produced on older leaves. The central portion of the spot is irregular and border is brownish, surrounded by a yellow halo
Management:
• Adapt various field sanitation measures
• Spray mancozeb @ 0.25% on the onset of disease and there after two sprays at an interval of 15 days if required.
