RESUMEN. Los papeles reactivos al pH (tirillas) podrían ser útiles para medir pH del suelo. El objetivo fue evaluar la precisión y exactitud de estas medidas. Se comparó la medición de pH (suelo:agua 1:2,5) en 51 muestras de suelo, por tres métodos:con electrodo (pH_electrodo); con tirilla inmediatamente de ser sumergida en el sobrenadante luego de 20 minutos de reposo (pH_T); y con la misma tirilla luego de dos horas de secada, rehumedecida y lavada (pH_T_RL). Se utilizaron tirillas Millipore®, graduadas por unidad de pH, estimándose los valores intermedios.

Prior research in 2005 and 2008 estimated planted forest investment returns for a set of countries and included some natural forest species in a few countries. This research has extended those analyses to a larger set of countries and focused on plantation species, for seven years. This research serves as a "benchmarking" exercise that helps identify comparative advantages among countries for timber investment returns, as well as other institutional, forestry, and policy factors that affect investments.

ABSTRACT. The apple production area in Uruguay is of approximately 4000 ha, with an average fruit production of 62,000 t per year. Apple is the most important crop within deciduous fruits, and has behaved as the most demanding, in crop technology, during the last years. Local climate and soil conditions in the south of the country, where the major apple producing area is located, can generate sanitary problems to apple trees.

ABSTRACT. Potential of production of pecan under Uruguayan agroecological conditions was estimated. In a pecan orchard representative of the south of the country, with 11-year-old trees, phenology stages were determined and setting was measured, as well as harvest. Determinations were done on two representative branches per tree of a sample of 22 trees. Climatic conditions of Uruguay, even though highly irregular, vary within a range suitable for pecan production.

ABSTRACT. Potential of production of pecan under Uruguayan agroecological conditions was estimated. In a pecan orchard representative of the south of the country, with 11-year-old trees, phenology stages were determined and setting was measured, as well as harvest. Determinations were done on two representative branches per tree of a sample of 22 trees. Climatic conditions of Uruguay, even though highly irregular, vary within a range suitable for pecan production.

ABSTRACT. ?Williams B.C.? pear was grafted on two pear rootstocks:?Farold®40? and ?Farold®69?, and on three clonal quince rootstocks:?BA 29?, ?Adams? and ?EMC? with and without ?Beurré Hardy? as an interstem. To evaluate the performance of these combinations in the south of Uruguay, grafted trees were planted in 2003 at INIA Las Brujas, ?Wilson Ferreira Aldunate? Experimental Station (34°40 S-56°20 W). Rows were 4.5 m apart and variable distance was used between plants according to rootstock:1.70 m (?BA29?, ?Farold®40? and ?Farold®69?), 1.50 m (?Adams?), and 1.30 m (?EMC?).

ABSTRACT. The objective of this study was to remove bottlenecks generally found in a computer program for average-information REML. The refinements included improvements to setting-up mixed-model equations on a hash table with a faster hash function as sparse matrix storage, changing sparse structures in calculation of traces, and replacing a sparse matrix package using traditional methods (FSPAK) with a new package using supernodal methods (YAMS); the latter package quickly processed sparse matrices containing large, dense blocks.

ABSTRACT. The objective of this study was to remove bottlenecks generally found in a computer program for average-information REML. The refinements included improvements to setting-up mixed-model equations on a hash table with a faster hash function as sparse matrix storage, changing sparse structures in calculation of traces, and replacing a sparse matrix package using traditional methods (FSPAK) with a new package using supernodal methods (YAMS); the latter package quickly processed sparse matrices containing large, dense blocks.