Two-dimensional difference gel electrophoresis (2-D DIGE) enables an increased confidence in detection of protein differences. However, due to the nature of the minimal labelling where only approximately 5% of a given protein is labelled, spots cannot be directly excised for mass spectrometry (MS) analysis and detection sensitivity could be further enhanced. Amersham Biosciences have developed a second set of CyDye DIGE Cy 3 and Cy5 dyes, which aim to overcome these limitations through saturation-labelling of cysteine residues. The dyes were evaluated in relation to their sensitivity and dynamic range, their useability as multiplexing reagents and the possibility of direct spot picking from saturation-labelled gels for MS analysis. The saturation-labelling dyes were superior in sensitivity to their minimal-labelling counterparts, silver stain and Sypro Ruby, however, the resulting 2-D spot pattern was significantly altered from that of unlabelled or minimal-labelled protein. The dyes were found to be useful as multiplexing reagents although preferential labelling of proteins with one dye over another was observed but was controlled for through experimental design. Protein identities were successfully obtained from material directly excised from saturation-labelled gels eliminating the need for post-stained preparative gels.

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Low maintenance vegetation may reduce N leaching following establishment compared to routinely fertilized conventional turfgrass lawns. Therefore, using a field‐scale facility we examined N leaching from contrasting residential landscape models established on a sandy soil. Four replications each of a St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] monoculture (SA) and a mixed‐species (MS) landscape were randomly assigned to 47.5‐m2 plots. Fertilizer N was applied to the SA landscape bimonthly at a rate of 50 kg ha−1 (total of 900 kg N ha−1), while the MS landscape was fertilized bimonthly at a rate of 40 kg N ha−1 only during establishment (total of 480 kg ha−1). Data were collected for 3 yr (16 mo to 52 mo after planting). Cumulative mean inorganic‐N leached was 4.1 kg ha−1 and 7.4 kg ha−1 for the SA and MS landscapes, respectively. Relatively long establishment requirements for the MS landscape led to significantly greater inorganic‐N leaching (5.2 kg ha−1) in year 1 of the study compared to the SA landscape (1.3 kg ha−1). After year 1, inorganic‐N leaching was comparable on both landscapes, although it was significantly less on the MS landscape in year 3 when no fertilizer was applied. Overall, inorganic‐N leaching was low (<2% of applied N) on both landscapes following establishment, indicating the importance of management practices rather than species composition for reducing N leaching from residential land use.