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Full-Text Articles in Agriculture
Impact Of Crop And Residue Management On The Physical And Chemical Stabilization Of Soil Organic Matter At Farm Level, Ana B. Wingeyer
Impact Of Crop And Residue Management On The Physical And Chemical Stabilization Of Soil Organic Matter At Farm Level, Ana B. Wingeyer
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
This dissertation explores changes over time in soil organic matter (SOM) stabilization of two irrigated production fields: a continuous maize sequence that was converted from no-till to conservation deep tillage (Site 1), and a no-till maize-soybean rotation (Site 2). An integrated approach using humic acid extractions and density-based physical fractionation of SOM within aggregate size classes was developed to evaluate the changes in SOM stabilization (physical protection, organo-mineral associations and humification). At Site 1, loss of SOM in the surface layer was compensated for by increased SOM in deeper soil layers with no net change in C stocks. Whole field …
Gata-Family Transcription Factors In Magnaporthe Oryzae, Cristian F. Quispe
Gata-Family Transcription Factors In Magnaporthe Oryzae, Cristian F. Quispe
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
The filamentous fungus, Magnaporthe oryzae, responsible for blast rice disease, destroys around 10-30% of the rice crop annually. Infection begins when the specialized infection structure, the appressorium, generates enormous internal turgor pressure through the accumulation of glycerol. This turgor acts on a penetration peg emerging at the base of the cell, causing it to breach the leaf surface allowing its infection.
The enzyme trehalose-6- phosphate synthase (Tps1) is a central regulator of the transition from appressorium development to infectious hyphal growth. In the first chapter we show that initiation of rice blast disease requires a regulatory mechanism involving an …