Epidemiology and Management of Blast (Pyricularia grisea (Cke.) Sacc.) of Finger millet (Eleusine coracana (L.) Gaerton)
KrishiKosh
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Title |
Epidemiology and Management of Blast (Pyricularia grisea (Cke.) Sacc.) of Finger millet (Eleusine coracana (L.) Gaerton)
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Creator |
PRAJAPATI, VIRAL P.
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Contributor |
SABALPARA, A.N.
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Subject |
millets, diseases, sowing, biological phenomena, yields, land resources, planting, fungi, genotypes, environmental degradation
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Description |
Finger millet [Eleusine coracana (L) Gaertn.] is one of the most important millet crops. During the survey, occurrence of blast disease in finger millet (cv. GN-4) was observed in serious proportion inflicting heavy losses in south Gujarat. Considering the seriousness of the disease, the present investigation was carried out on various aspects to generate scientific informations on this important pathological problem and to develop suitable management strategies to prevent the crop losses. The pathogen involved to cause the blast in the area was identified as Pyricularia grisea earlier by Waghunde (2012). The pathogen attacked mostly the lower leaves and disease starts from the lower to upper leaves. Disease occurs at all the phases viz. leaf, neck and finger blast. The disease appears on leaf lamina with typical spindle shaped spots. Under high humid condition, such spots found to progress and enlarged rapidly. The margin of the lesion was brown to blackish brown. Such fully developed lesions were coalesced and gave a blasted appearance. The ears hang down from the stalk at the point of infection and sometimes break away. The infection on fingers usually begins from the apical portion and runs towards the base, even pathogen attacks on apparently healthy ears. The pathogen attacks the seeds resulting in shriveled and blackened. The extent of damage depends on the stage of infection and the weather condition. The entire finger length of the ear was affected. When the intensity of the disease was severe, most of the leaves became yellowish, dried up and the field presented a blighted appearance. Blast was found in severe proportion in both the popular varieties viz., GN-4 and local in Dang district. While lowest in Valsad followed by Navsari districts of south Gujarat. Losses due to the blast was estimated up to Grain yield (35.78%) and Fodder yield (43.72%). Due to leaf, neck and finger blast of finger millet, losses were found in all the growth parameters and ultimately affected in reduction of 1000 grain weight (40.13%). Young crops (1 to 2 months) mostly remained free from the infection of the blast. The infection started during August and attained its peak on completion of major rainfall i.e. after 35th MSW. During the major progress (35th to 39th MSW), average temperature remained around 25°C and 86 per cent relative humidity with moderate rainfall. Window periods for leaf blast (24th-25th August to 31st August-1st September), neck blast (31st August-1st September to 7th-8th September) and finger blast (31stAugust-1stSeptember to 28th September-29th September) were recorded. Maximum temperature, temperature range, relative humidity, rainfall and rainy days were found significant and positively correlated, while, minimum temperature and wind speed were significant and negatively correlated with leaf, neck and finger blast disease. Correlation coefficient study between weather parameters and disease intensity indicated that all the parameters jointly played an important role in the development of disease. The multiple regression for leaf blast [Ŷ= -42.25 + 0.87(X1) + 2.29(X2) + 0.69(X3) + (-0.92)(X4) + (-0.03)(X5) + 0.40(X6) + (-1.00)(X7)], neck blast [Ŷ = -138.49+ 0.95(X1) + 3.78(X2) + 1.99(X3) + (-1.52)(X4) + (-0.02)(X5) + (-2.38)(X6) + (-0.95)(X7)] and finger blast [Ŷ = 5.91 + (-1.22)(X1) + 2.75(X2) + 1.07(X3) + (-1.12)(X4) + 0.01(X5) + (-6.15)(X6) + (-0.41)(X7)], where X1 = Maximum temperature, X2 = Minimum temperature, X3= Maximum relative humidity, X4 = Minimum relative humidity, X5 = Rainfall, X6 = Rainy days, X7 = Wind speed] were developed for the forecasting. On the basis of these, the predicted per cent leaf blast intensity, neck and finger blast incidence at any peak was found closely related with observed leaf blast intensity, neck and finger blast incidence. Amongst, 10 genotypes of finger millet screened against blast disease, the genotypes GPU-67 showed resistant reaction while GN-5, GPU-48, PR-202, RAU-8, and KOPN-235 exhibited moderately resistant reaction against the blast disease. Genotypes GPU-28 and VL-149 showed susceptible reaction. However, GN-4 and VR-708 showed highly susceptible against blast disease of finger millet. Among all the tested fungicides, bioagent and phytoextract, tricyclazole (0.6 g/l), P. aeruginosa (6 ml/lit), iprobenfos (1ml/l) and tebuconazole + trifloxystrobin (1g/lit) proved better for the management of the disease as well as for getting higher grain and fodder yield. Seed treatment with carbendazim, 2g/kg seed + 2 sprays of tricyclazole, seed treatment with carbendazim, 2g/kg seed + 2 sprays of iprobenfos, and seed treatment with Pseudomonas aeruginosa, 10g/kg seed + 2 sprays of P. aeruginosa, found superior for the control of blast disease of finger millet as well as for getting higher grain and fodder yield. |
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Date |
2016-05-03T15:11:23Z
2016-05-03T15:11:23Z 2013-08 |
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Type |
Thesis
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Identifier |
http://krishikosh.egranth.ac.in/handle/1/65753
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Language |
en
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Format |
application/pdf
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Publisher |
Navsari Agricultural University, Navsari
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