Control of economically important disease of cereals Presented

Control of economically important disease of cereals Presented by: Gaurav Kumar Pal M. Sc. Applied Microbiology 3 rd sem Department of Microbiology CCS University Meerut 250004

Introduction : • • • 1. 2. 3. 4. Ø Different types of cereals crops are affected by various type of bacterial fungal &viral disease. They damage the grains &straw yield of cereals crops. These cereals crops are – Rice (Oryza sativa) Wheat (Triticum spp. ) Maize (Zea mays ) Barley (Hordeum vulgare) In these crops rice & wheat crops grown mostly.

Disease in Rice : BLAST Disease : Pathogen: -Pyricularia oryzae Symptoms: Ø Aerial parts of plant infected. Ø Spindle shaped spots on leaves. Ø Centre is whitish grey spots with brown margins. Rice blast disease

Control : Ø By resistant varieties • Co 4, TKM-1, Co 29, IR-579, A-249, A-200, T-603, T-141 etc. Ø By seed treatment • immerse seed on 0. 2% Solution of Kalimat B for 24 hrs. Ø By spraying • Spraying Bordeaux Mixture before & after the flowering of the crop. Ø By proper manuring • Should not used Nitrogen fertilizer in excess amount &used potassic &phosphoric manure.

Brown spot (fungal blight) Ø Pathogen : Helminthosporium oryzae Ø Symptoms: • Development of dark brown spots on the upper surface of the leaf. • Disease appears after transplanting. • Infected all parts of plant except roots. • Seed borne disease. Brown spot disease

Control : Ø By resistant varieties • CH-13, TI-41, T-2114, Bam-10, Nagra 41 -14, IET-13238, CR-8430 etc. Ø By seed treatment • • • seed treatment with ceresan. seed treatment with agrosan GN. By hot water treatment 50 -52°C for 10 minutes. Ø By spraying • • Spraying Bordeaux Mixture Spraying dithane Z-78(organic sulfur compounds ) Ø By proper manuring • Should not used Nitrogen fertilizer in excess amount. • Level of nitrogen &phosphorus should be well balanced.

Bacterial blight : Ø Pathogen : -Xanthomonas oryzae Ø Symptoms: • • • Appearance of dull greenish water soaked or yellowish spot on the tip of leaf. Bacteria induce wilting of plants. Occurs within 3 -4 weeks after transplantation. Lesions turn yellow to white as the disease advances. Severely infected leaves tend to dry quickly. Seed borne disease. Seedling wilt by bacterial blight disease

Control: Ø By field sanitation • removing weed hosts, rice straws. Ø By resistant varieties • IET- 9190, CR-316 -636, RP 2151 -165 -3 -1, RP 2151 -21 -22, etc. Ø By seed treatment • • Seed treatment with bleaching powder (100µg/ml) and zinc sulfate (2%) reduce bacterial blight. Soaking of seed for 8 hrs in ceresan. Ø By spraying • Control of the disease with copper compounds, antibiotics and other chemicals highly effective. Ø By proper manuring • • Proper application of fertilizer, especially nitrogen. Proper plant spacing are recommended for the management of bacterial leaf blight.

False smut disease Ø Pathogen- Ustilaginoidea virens Ø Symptoms • Individual rice grain transformed into a mass of spores or yellow fruiting bodies. • Growth of spores enclose floral parts. • Immature spores are smooth, yellow, and covered by a membrane. • Growth of spores result to broken membrane. • Mature spores orange and turn yellowish green or greenish black. • Only few grains in a panicle are usually infected. Infected penicle

False smut controlØ Crop rotation • Effective against disease. Ø Spraying • At preflowering stages spraying of carbendazim fungicide and copper base fungicide can effectively control the disease. • Applying captan, captafol, fentin hydroxide, and mancozeb can be inhibited conidial germination. • Three spray of 0. 4% Bordeaux mixture (when plants are about 3 months) Ø Resistant varieties • Sabarmati, Saket-4, Sona, Surya, Vijaya, Jayanti, IR 22, IR 26, IR 28 etc. Ø field sanitation • Destruction of straw and stubble from infected plants is recommended to reduce the disease.

Tungro disease of virus Ø Pathogen : -rice tungro virus Ø Symptoms: • discoloration begins from leaf tip and then lower leaf portion. • infected leaves may also show striped appearance. • reduced tillering • delayed flowering, which may delay maturity • most panicles sterile or partially filled grains and covered with dark brown blotches. Ø Control: • Use of resistant varieties Tungro disease

Disease of wheat Ø Rust Disease : Ø Ø 1. 2. 3. Ø Earliest known disease of crop plants Three different forms of rust attack on wheat crops. Black or stem rust (Puccinia graminis tritici) Leaf or Brown or orange rust (Puccinia triticina Eriks. ) Yellow or stripe rust(Puccinia striiformis) Found in all over the world. Rust disease

Black or stem rust disease Ø Pathogen: - Puccinia graminis tritici Ø Symptoms: • Having large spore mass. • Pustules are dark reddish brown. • Occur on both sides of the leaves, & stems & on spikes. • The infection sites feel rough to the touch. Stem rust disease

Leaf rust disease Ø Pathogen: - Puccinia triticina Eriks Ø Symptoms: • Small brown pustules develop on the leaf blades. • They may group into patches in serious cases. • Infectious spores are transmitted via the soil • Reddish-orange urediospores develop. • rupture the epidermis of the leaf surface as the spores mature. Leaf rust disease

Yellow rust disease Ø Pathogen: - Puccinia striiformis Ø Symptoms: • Appearance of yellow-colored stripes on each leaf blade. • These yellow stripes are yellow colored urediniospores. • The disease usually occurs early in the growth season, when temperature ranges between 2 and 15°C. • Weakened plants. • loss in number of grains per spike and grain weight. Yellow rust disease

Control of rust disease Ø By resistant varieties • HD 2009, SONALIKA, WH 147, S 308, HW 741, WL 614, C 306 etc. Ø By spraying • Spraying nabam &zinc sulphate. • Spraying dithane , zineb, etc. • Spraying actidione etc. Ø By proper manuring • Should not used Nitrogen fertilizer in excess amount. • Rust resistance increased by the use of potassic manure. Ø field sanitation • Destruction of self shown plants is recommended to reduce the disease. Ø Cultivation of early maturing varieties • early maturing escape from the attack of rust.

Loose Smut disease Ø Ø • • Pathogen: - Ustilago nuda Symptoms: Seed borne disease. Disease seen only on the emergence of the ears. • The black powder is seen in the ear instead of flowers. • Masses of smut spores replace the entire head of plants. Loose smut disease

Control of Loose Smut disease Ø By resistant varieties • Ø • • • NP 710, NP 729, NP 823, MP 108, MP 144, MP 168, Bansi 224, etc. Sanitation Infected ears should be burned outside the field. Spore is destroyed. By seed treatment By hot water treatment 50 -52°C for 10 minutes. By solar treatment Clean seeds should be used. Ø By chemical treatment • Kept 40 -50 hrs in 2%spergon or chlorose destroyed pathogen.

Karnal bunt disease Ø Pathogen: -Tilletia indica Ø Symptoms: • A few kernels per spike to be affected by this disease. • Diseased kernels can be easily detected by visual inspection: • A mass of black teliospores replaces a portion of the endosperm. • Diseased kernels give off a fishy odor when crushed. Bunt disease in wheat grains

Healthy seed 2 % Infection 10 % Infection 30 % infection 50 % infection 100 % infection

Karnal bunt disease control Ø By resistant varieties • Kalyan sona, S 227, PV 18, HD 2012, 4513, 4519, IWP 72, 87, 129, WL 885, 1581 etc. Ø By seed treatment • By disinfesting seeds in a 1. 5% solution of sodium hypochlorite plus Tween 20 for 10 minutes • Clean seeds should be used. Ø By crop rotation • Proved beneficial for disease control.

Powdery mildew disease Ø Pathogen: -Blumeria graminis sp. Tritici Ø Symptoms: • White to pale gray, fuzzy or powdery colonies of mycelia, and conidia. • Present on the upper surfaces of leaves and leaf sheaths (especially on lower leaves) , and sometimes on the spikes. • Older fungal tissue is yellowish gray. • This superficial fungal material can be rubbed off easily with the fingers.

Control of Powdery mildew disease Ø By resistant varieties • NP 710, NP 718, E 750, C 591, Sonora HD 2204, hd 2074, VL 401, etc. Ø By chemical treatment • By using sulpher dusting. Ø By crop rotation • Proved beneficial for disease control. Ø By spraying • Spray with 0. 1% benlate • Spray with 0. 1%Karathane

Leaf blight disease Ø Pathogen: -Alternaria triticina Ø Symptoms: • Small, chlorotic, oval shaped lesions appear. • These lesions become irregular in shape. • The chlorotic borders of the lesions may become diffuse and turn light to dark brown in color. • Lesions are difficult to distinguish from spot. • Infection usually starts on the lower leaves, but symptoms can be found on all plant parts. Leaf blight disease

Control of Leaf blight disease ØBy resistant varieties • NP 4, NP 52, NP 200, NP 809, NP 824 etc. Ø Sanitation • Infected plants should be burned outside the field. Ø By seed treatment • By hot water treatment 50 -52°C for 10 minutes. • Clean seeds should be used.

Disease in maize ØHead smut disease ØPathogen: Sphacelotheca reiliana ØSymptoms : Øthe fungus penetrates the seedlings and grows inside the plant without showing symptoms, ØInfection of the tassel also leads to reduced pollen production. ØAbnormal development of the tassels. ØMasses of black spores in place of the normal ear. ØControl of disease : ØBy sanitization ØBy crop rotation ØBy resistant varieties Head smut disease in corn

Brown spot disease : • • Pathogen: -Physoderma maydis Symptoms : Occurs in areas of high rainfall and high temperatures. It attacks leaves, leaf sheaths, stalks. Symptoms develop on leaf blades and consist of small chlorotic spots. Spots on the mid-ribs are circular and dark brown, while lesions on chlorotic spots. Nodes and internodes also show brown lesions. Ø Control Ø By field sanitation Ø Resistant varieties Brown spot disease in corn leaf

Ear rot disease Ø Pathogen: Fusarium graminearum Fusarium moniliforme Ø Symptoms: Ø Ø Ø Ear infection begins as white mycelium. later turns reddish-pink, in infected kernels. The fungus produces mycotoxins. Infected kernels develop a cottony growth. The fungus produces mycotoxins known as fumonisins, which are harmful to several animal species. Ear rot disease in corn

Control of Ear rot disease • • Resistance varieties Cultivation of varieties that are resistant to ear rots is the most practical and cost-effective means of ear rot management. • Chemical control • • • Where the crop is infected systemically with Fusarium species, application of fungicide early in the season can limit ear infection. Management of insect pests (ear borers) will reduce infection of the ear through injury sites caused by insect feeding. • Proper storage • Storing grain at low moisture (below 15%) reduces the disease. • Cultural control • Management of infected crop debris will reduce the amount of disease.

Reference Ø Agrios, George N. , Plant Pathology. 5 th ed. Burlington, MA: Elsevier Academic Press, 2005. Ø Pandey b. p. , plant pathology pathogen &plant disease(2010), page no (147 -214). s. chand &co. ltd new Delhi. Ø http: //www. knowledgebank. irri. org/Rice. Doctor/in dex. php/information-sheets-mainmenu-2730 Ø http: //wheatdoctor. cimmyt. org/en/pests-adiseases/list/122? task=view Ø http: //en. wikipedia. org/wiki/Bright's_disease#Sy mptoms. Ø http: //maizedoctor. cimmyt. org/en/pests-anddiseases/list/218