5 research outputs found
Effects of Variety and Fungicidal Rate on Cercospora Leaf Spots Disease of Groundnut in the Sudan Savanna
A field study was carried out at the University of Maiduguri Teaching and Research Farm during the 2006, 2007 and 2008 cropping seasons to evaluate the effects of variety and fungicidal rate on Cercospora leaf spot disease of groundnut. The experimental design used was Randomized Complete Block Design (RCBD) with twelve treatment combinations of three varieties of groundnut (Ex-Dakar, RRB and ICGV-86024) and four levels of fungicidal rate (0, 1, 2 and 4 kgha¥„1 of fungicide mancozeb)
replicated three times. Disease incidence and disease severity were significantly higher in Ex-Dakar and 0 kgha¥„1, thus had lower yields. Higher seed and haulm yield were recorded by RRB, ICGV-86024, as well as 2 and 4 kgha¥„1 as a result of lower disease incidence and severity
Efficacy of Argentinean propolis extracts on control of potato soft rot caused by Erwinia carotovora subsp.
Erwinia carotovora subsp. cause the potato soft rot, which is a major disease in agriculture. Antibacterial agents currently applied on potato soft rot often offer a restricted control and have several disadvantages. Propolis has shown a wide range of antimicrobial activity, although its effect has not been investigated on E. carotovora subsp. In this work, we tested extracts from propolis samples of Northwest Argentina against E. carotovora subsp.RESULTS: Ethanolic propolis extracts (EPEs) from samples of Santiago del Estero province, particularly from sample 4 (EPE4), showed the highest antibacterial activity, which was associated with the highest content of flavonoids. 2âČ,4âČâDihydroxychalcone, 2âČ,4âČâdihydroxyâ3âČâmethoxychalcone, galangin, and pinocembrin were identified as antibacterial constituents of EPE4. 2âČ,4âČâDihydroxychalcone showed an antibacterial activity (minimum inhibitory concentration, MIC = 0.3?1.2 ÎŒg gallic acid equivalents (GAE) mLâ1; minimum bactericidal concentration, MBC = 0.6?4.8 ÎŒg GAEâmLâ1) lower than that of bacterimycin (MIC = 2.4?9.6 ÎŒgâmLâ1; MBC = 19.2?38.4 ÎŒg GAE mLâ1) and streptocycline (MIC = 19.2?38.4 ÎŒgâmLâ1; MBC = 38.4?76.8 ÎŒgâmLâ1). Preventive assays on unwounded and wounded potatoes showed that their immersion in EPE4 containing 87.5 ÎŒg GAEâmLâ1 or streptocycline containing 40âÎŒgâmLâ1 was equally effective in controlling potato soft rot, reducing the disease incidence by 64.6?67.0% (unwounded tubers) and 88.0?86.0% (wounded tubers) and the disease severity by 49.8?49.8% (unwounded tubers) and 54.5?68.5% (wounded tubers).CONCLUSIONS: Flavonoidârich propolis extracts from Northwest Argentina efficiently reduced in vivo the incidence and severity of potato soft rot caused by E. carotovora subsp.Fil: Sampietro, Diego Alejandro. Universidad Nacional de TucumĂĄn. Facultad de BioquĂmica, QuĂmica y Farmacia; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - TucumĂĄn; ArgentinaFil: Bertini Sampietro, Maria Sofia. Universidad Nacional de TucumĂĄn. Facultad de BioquĂmica, QuĂmica y Farmacia; ArgentinaFil: Vattuone, Marta Amelia. Universidad Nacional de TucumĂĄn. Facultad de BioquĂmica, QuĂmica y Farmacia; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - TucumĂĄn; Argentin