Integrated disease management of bacterial leaf blight of rice (Xanthomonas Oryzae pv. Oryzae)
| dc.contributor.advisor | Rai, Bimla | |
| dc.contributor.author | Bala, Archana | |
| dc.date.accessioned | 2017-11-06T05:52:50Z | |
| dc.date.available | 2017-11-06T05:52:50Z | |
| dc.date.issued | 2014 | |
| dc.description.abstract | Bacterial leaf blight of rice incited by Xanthomonas oryzae pv. oryzae is a dominant disease of rice of widespread occurrence and inflicting heavy damage to the crop in Bihar in Kharif season. The studies mainly adhered to pathogenicity, effect of RRb, botanicals and new chemicals against percentage inhibition over control, also evolution of RRb, botanical and new fungicides for effect of seed treatment for seed germination, Screening of rice varieties/entries for disease resistance against Xanthomonas oryzae pv. oryzae. The pathogenicity of Xanthomonas oryzae pv. oryzae was proved on rice variety (Pusa Basmati) by injection infiltration method and subsequently Koch’s postulates were established. Kresek occurs in early stage. In later stage blighting starts from the tip of leaves to the base, straw turned yellow. Yellow bacterial ooze appears on the surface which dries up into bead like incrustations. Morphological studies of Xanthomonas oryzae pv. oryzae showed that The pathogen are gram negative, short rod, with rounded ends, single or in pairs, measuring 1.1 to 2.0 X 0.5 to 0.8 µm in size, motile with single polar flagellum, capsulate and non-spore forming. RRb’s which occurred frequently in soil samples of Pusa farm under RAU, Pusa, Samastipur ,was selected for antagonism study against Xanthomonas oryzae pv.oryzae causing bacterial leaf blight of rice. In dual culture, RRb-c, RRb-d and RRb-e completely overgrew (100 %) the pathogen colony in 144 hours and completely inhibited the formation Xanthomonas oryzae pv. oryzae. The aqueous leaf extract of botanicals were effective i.e Allium sativum (87.33%), Azadirachta indica ((71.23%) and Zingiber officinale (60.83%) were found to be antagonistic towards Xanthomonas oryzae pv.oryzae @ 15% conc. after 48 hours. Three chemicals found effective in reducing severity of BLB were Blitox-50+Streptocycline (70.25%), Ergon 44.3 SC (66.4%) and Nativo 75WG (49.91%) @50 ppm conc. by poisons food technique respectively. In respect of botanicals, all botanicals were effective against BLB. The maximum inhibition was found with botanical by Allium sativum (87.33%). However, Azadirachta indica (71.23%) and Zingiber officinale (60.83%) @15% conc. after 48 hours were also found to be other effective treatments. Seed treatment with RRb (Rice rhizobacteria), RRb-e (93%) & RRb-d (89%) isolates was effective in increasing seed germination and also enhance root and shoot length @ 15% concentration. Seed treatment with Zingiber officinale, Azadirachta indica and Allium sativum @ 15% conc. resulted in 88%, 85% and 72% germination respectively. In respect to new chemicals, for better germination was recorded seed treatment with Blitox-50 +Streptocycline (88%), Nativo 75WG (80%) and Ergon 44.3 SC (72%) @ 50 ppm concentration. In varietal screening out of 758 varieties/entries, only 125 entries were highly resistant under natural condition against the BLB in both trial i.e. NSN1 and NSN2.Rest of varieties/entries showed moderately resistant or either moderately susceptible or susceptible or highly susceptible reaction against the bacterial blight disease. | en_US |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/5810034740 | |
| dc.keywords | Rice, Bacterial Leaf Blight, Xanthomonas oryzae, Disease control. | en_US |
| dc.language.iso | en | en_US |
| dc.pages | 67+xiii | en_US |
| dc.publisher | Rajendra Agricultural University, Pusa (Samastipur) | en_US |
| dc.sub | Plant Pathology | en_US |
| dc.subject | null | en_US |
| dc.theme | Control of Bacterial leaf blight on rice. | en_US |
| dc.these.type | M.Sc | en_US |
| dc.title | Integrated disease management of bacterial leaf blight of rice (Xanthomonas Oryzae pv. Oryzae) | en_US |
| dc.type | Thesis | en_US |