Ana Cecilia González-Franco

Molecular and biological characterization of a recombinant isolate of potato virus Y from Mexico

Abstract An isolate of potato virus Y (PVY), PVY-M3, was subjected to biological characterization on potato indicators and to whole-genome sequencing. PVY-M3 induced a local and systemic hypersensitive resistance (HR) response in potato cultivar Maris Bard expressing the Nz gene while inducing no HR in potato cultivars Desiree and King Edward, carrying Ny and Nc genes, respectively. These HR responses, combined with a lack of vein necrosis in tobacco, clearly defined PVY-M3 as an isolate of the PVYZ strain. Recombination analysis demonstrated that PVY-M3 had a typical European PVYNTN genome with three recombinant junctions, and PVYN and PVYO were identified as parents.

Comparison of three systems of decomposition of agricultural residues for the production of organic fertilizers

Organic wastes (OW) of diverse nature must be subjected to controlled decomposition processes to avoid risks of contamination and obtain products useful for agriculture. The objective of the present study was to compare over time physical, chemical and enzymatic parameters of OW transformed as vermicomposting (VC), semicomposting (SC) and composting (CP) for elaboration of organic fertilizers. A mixture of bovine manure and sawdust was subjected to each of three systems for 183 d. Temperature, total N (Nt), organic C (OC), C/N ratio, pH, enzymatic urease activity (EUA), germination index (GI) and electrical conductivity (EC) were measured throughout the time of study. The variables evaluated showed significant differences between time and treatment. The temperature ranged between 20 and 34 °C in VC and SC, while in CP between 20 and 61 °C. All three systems reduced the C/N ratio to less than 15/1. The CP product had higher pH, EC, and EUA values than both VC and SC. The VC product had the highest GI values. All the products obtained at 183 d were within the parameters to be considered as organic fertilizers, but the SC product transformed into an organic fertilizer fastest and had least water usage.