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This book of Diseases of Field Crops & their Management-II is a carefully written for undergraduate class and is completely in accordance with the latest 5th Deans’s Committee Recommendations Guidelines.

Rust The rust of wheat has been studied more than any other disease in the world. In India, K.C Mehta and his associates studied this disease with exemplary zeal. Three rusts of wheat are known. These are Black stem rust, caused by Puccinia graminis tritici, Brown rust (leaf rust), caused by Puccinia recondita, and Yellow rust, caused by P? striiformis. Brown and yellow rusts cause more damage thant the black rust, because of early appearance in the season.

Diagnostic Symptoms • Practically all above ground parts are affected, but stalks are the main targets of stack. • Spindle leaves (third or fourth) starts drying. • Further stalks becomes discolored and hollow.

Diagnostic Symptom • Circular to oval, dark brown to black spots appear on the leaves.The spots enlarge into round to irregular spots with concentric rings and coalesce causing blighting and withering of leaves. • These are surrounded by chlorotic zone with grey white necrotic center.

Diagnostic Symptoms • Intially chlorotic (yellowed) lesions and sometimes galls appeared on the upper leaf surface. • There are corresponding white blister-like dispersal pustules of sporangia on the underside of the leaf.

Diagnostic Symptoms • At first pale-green chlorosis, typically appear on lower leaves and extending up the plant.Leaves eventually take on a dull-yellow colour, wilt and the plant collapses and dies.

Diagnostic Symptoms • Symptoms can occur at both the seedling and plant developmental stages and appear as patches in the field • It usually occurs near or at the reproductive stages (flowering to podfilling) of crop growth

Wilt Fusarium oxysporum f.sp. vasinfectum Diagnostic Symptoms • Disease affects the crop at all stages.

Powdery Mildew Erysiphe polygoni Diagnostic Symptoms • At first symptom appears on leaves. • White floury patches appear on both surface of leaves as well as tendrils, stem and pod.

Anthracnose Colletotrichum gloeosporioides (Glomerella cingulata) Diagnostic Symptoms • Disease produces symptoms like leaf spot, blossom blight, withertip, twig blight and fruit rot • Symptoms on leaves show as gray to brown spots with dark margins and a yellow halo. The spots later enlarge and coaleasce to form sizable necrotic areas.

Gummosis Phytophthora spp Diagnostic Symptoms • Dark water soaked large patches appear on the basal portions of the stem near the ground level.

Downy Mildew Plasmopara viticola • Downy mildew of grapes was catastrophic in France in 1878.

Scab Ventruia inaequalis (Spilocaea pomi Fr?) Diagnostic Symptoms • Symptoms generally noticed on leaves and fruits.

Leaf Curl Taphrina deformans Disease Symptoms • Initially yellowish to reddish areas appear on leaf blade of young leaves in the spring.

Leaf Spot (Mycosphaerella fragariae teleomorph, Ramularia brunnea Peck anamorph)? Disease Symptoms • Older leaves usually show purple spots (3-6 mm in diameter) on the upper surface, sometimes with a slightly darker halo

Late Blight Phytophthora infestans • Phytophthora in Greek means “plant destroyer”(phyto=plant, phthora= destroyer).

Downy mildew Pseudoperonospora cubensis Diagnostic Symptoms • Yellow, angular spots restricted by veins resembling mosaic mottling appear on upper surface of leaves .

Purple blotch Alternaria porri Diagnostic Symptoms • Disease symptoms occurs on leaf and flower stalks.

Anthracnose or Fruit Rot and Die Back Colletotrichum capsici Diagnostic Symptoms Dieback symptoms • Small, circular to irregular, brownish black scattered spots appear on leaves .

Leaf spot Colletotrichum capsici Diagnostic Symptoms • Initially oblong brown spots having about 4-5 cm in length and 2-3 cm in width with grey centres surrounded with yellow hallo are found on the leaves .

Stem gall Diagnostic Symptoms • Symptom appears in the form of tumor-like swellings of leaf veins, leaf stalks, peduncles, stems as well as fruits. • Infected veins show a swollen hanging appearance to the leaves.

Botrytis Gray Mould Diagnostic Symptoms • Appearance of a gray, fuzzy mold on flowers, leaves or stems of or plants. Also called, “gray mold”.

Powdery mildew Sphaerotheca pannosa var. rosae (Sphaerotheca pannosa) Diagnostic Symptoms • A white, powdery fungal growth on the upper, lower or both leaves and shoots.

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