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To improve fertilisation recommendations in organic farming systems and nitrate vulnerable zones, the response of white cabbage to the application of increasing rates of mineral N (0, 90 and 180 kg ha-1) fertiliser in combination with increasing rates (0, 20 and 40 t ha-1) of an organic fertiliser from the composting process (182 days) of the solid fraction (SF) of dairy cattle slurry, was assessed in the summer season in NW Portugal. Cabbage yield was strongly related to mineral N application with an N recovery rate over 70%, but was not associated to SF compost application, except for treatments without mineral N fertilisation where cabbage dry weight increased (P

Cabbage (B. oleracea var. capitata) response to 0 and 30 t/ha of mature cow and horse manure compost (C1: C/N=16.5) and of composted dairy cattle slurry solid fraction with different maturation periods and C/N ratios (C2: C/N=18.4; C3: C/N=21.8) and, incorporated into the soil one month before planting (B) and at planting (P), was evaluated throughout a randomized block design experiment. At the site, a mineral fertilized cabbage experiment was also carried out, with 180 kg ha-1 of mineral N. All crops were evaluated 0, 20, 34, 48 and 62 days after planting. The mineral fertilized cabbage showed increased growth rate compared to the organic crops with a final yield of 79.6 t/ha. The timing of compost application did not significantly affect crop growth, except for C2. Organic cabbage yield with the compost treatment C2B and compost C1 (mean of both application dates) were respectively 49.7 and 51.8 t/ha. Yield of crops grown with C2P and C3 were lower (mean of 36.9 t/ha) compared to C2B and C1 and were not significantly different from unfertilized crops (28.7 t/ha). Dry matter content was lower for mineral fertilized crops (9.2%) than for organic crops (mean 12.2%) and differences between the percentage of crop waste residues of organic (25.6%) and mineral fertilized (29.8%) crops were not statistically significant. The apparent compost N efficiency rate decreased from 13.7 to 11.2 and 9.2%, whereas N immobilization period increased from 37 to 42 and 45 days, respectively for C1, C2 and C3. Consequently, N uptake decreased from 99.7 (C1) to 89.8 (C2) and 79.5 kg/ha (C3). The N recovery rate for the mineral N application in the mineral fertilized cabbage crop was 55.3% (N uptake of 99.5 kg/ha). This study shows that as the C/N of the composts decreased, the period of N immobilisation decreased and the apparent compost N efficiency rate by the crop increased. Consequently, during the cabbage growing period more mineral N was available from the mineralisation of composts with a lower C/N ratio, as well as for the earlier compost application for the mature compost C2.

Cantaloupensis melons are aromatic and fast senescing, whereas Inodorus have less odor and are slower senescing. Modified atmosphere packaging (MAP) is used to reduce respiration rate and extend shelf-life but may alter the synthesis of volatile compounds. We assessed the effects of passive MAP and controlled atmosphere (CA; 5 kPa O 2 + 10 kPa CO 2 ) upon quality and volatile production by fresh-cut 'Cantaloupe' and 'Honeydew' melons, stored at 5°C for 14 days. O 2 concentration inside the MAP packages decreased during the 14 days, to 11.1 and 14.2 kPa, in 'Cantaloupe' and 'Honeydew', respectively. CO 2 levels increased to 11.3 and 7.9 kPa during storage, for 'Cantaloupe' and 'Honeydew', respectively. In MAP, during the first 4 days of storage, cantaloupe cubes softened at a higher rate (2.0 N.day -1 ) than 'Honeydew' cubes (0.9 N.day -1 ). Conversely in CA, fresh-cut 'Honeydew' softened faster (1.9 N.day -1 ) than fresh-cut 'Cantaloupe' (0.9 N.day -1 ) which, softened faster between days 4 and 7 (2.1 N.day -1 ). Initial 'Cantaloupe' respiration was 17.5 ml CO 2 .kg -1 .h -1 , which increased to 63.8 and 43.4 ml CO 2 .kg -1 .h - 1 when stored in CA and MAP, respectively. Initial respiration of 'Honeydew' melon was 7.7 ml CO 2 .kg -1 .h -1 and increased to 55.5 and 30.0 ml CO 2 .kg -1 .h -1 when stored in CA and MAP, respectively. Volatile compounds that are known to be flavor-important in melons, were extracted using Stir Bar Sorptive Extraction (SBSE) and quantified via GC-MS. The production of acetate esters increased in both melons stored in MAP, but decreased in 'Cantaloupe' under CA conditions. Non-acetate esters increased in both cultivars and storage conditions. Alcohols, initially more abundant in 'Honeydew', underwent a decrease throughout storage. Aldehydes, initially more abundant in 'Cantaloupe', decreased in both melons for MAP but not in 'Honeydew' stored in CA. Lower O 2 availability in fresh-cut fruit, stored under CA conditions utilized in this experiment, likely suppressed some of the acetate esters relevant to the aroma of fresh-cut melon.