Banana fruits, Musa (AAA Group, Cavendish subgroup) 'Williams' were ripened in air at 20°C with ethylene. Pulp began softening between days 1 and 2 of ripening and reached a maximum by the fourth day. Total pulp cell wall uronic acid and uronic acid soluble in 40 mM EDTA, 50 mM acetate, pH 4.5, also began to decrease and increase respectively between days I and 2. By day 8, total uronic acid had decreased from 102 to 4.4 mg g-I fresh weight, and had become entirely soluble in EDTA-buffer, while EDTA-buffer-soluble uronic acid had increased from 2.3 to 4.5 mg g-I. The molecular size distribution of the EDTAbuffer-soluble uronic acid was unchanged up to day 4, when there was a slight loss in the proportion of smaller species. The average molecular size of this uronic acid did not change significantly during 8 days of ripening (relative to dextrans, M , 36 kDa; M, 173 kDa). The large change in total content and extractability of cell wall polyuronides that correlated with softening was inconsistent with depolymerisation by endopolygalacturonase (EC 3.2. I. 1 3 , reduced cross-linking of polyuronides by calcium, or extraction artefacts.

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Banana (Musa, AAA) bunch-sections consisting of one hand attached to a short section of main-stalk were wound-inoculated with cultures of fungi isolated from diseased fingers, crowns, or main-stalks and stored in sealed polyethylene bags containing 3-7% oxygen, 10-13% carbon dioxide and <0.1 /zl 1-1 ethylene for 40 days at 20°C, then ripened with ethylene in air for nine days. Colletotrichum musae, Fusarium moniliforme var. subglutinans and Nattrassia mangiferae caused high infection incidence in unripe fingers during storage. These fungi also caused crown rot, but only F. moniliforme var. subglutinans caused main-stalk rot. Alternaria alternata and F. pallidoroseum both caused some infection in unripe fingers during storage, and both subsequently caused crown rot. A. alternata also infected main-stalks. Lasiodiplodia theobromae and Phomopsis musicola infected only ripening fingers, and F. culmorum infected only crowns and main-stalks. The pathogenicity of some isolates was changed by interposing storage between inoculation and ripening. C. acutatum and C. gloeosporioides became unable to cause disease and F. culmorum caused less disease. In contrast, A. alternata and F. pallidoroseum became pathogenic to fingers, crowns and, in the case of A, alternata, to bunch main-stalks. Benomyl and prochloraz (500 mg 1-1) controlled most diseases at inoculation sites, and naturally-occurring main-stalk rot. Prochloraz controlled more diseases than benomyl, and this control was usually more effective.Key words: Banana; Musa; Rot, finger, stalk, crown, bunch main-stalk; Benomyl; Prochloraz INTRODUCTIONModified atmosphere (MA) storage of bananas is a versatile technology applicable to a wide range of cultivars, including AA, AAA, AAB and ABB or BBB

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Composition and sensory acceptability of fresh market tomatoes (Lycopersicon esculentum Mill ‘Flora-Dade’) were investigated to determine the influence of harvest maturity on quality after fruit had ripened to a tableripe stage. Tomatoes were harvested from commercial plots at ‘immature green’, ‘mature green’, ‘breaker’, ‘light pink’, and ‘light red’. The differentiation between tomatoes harvested ‘mature green’ and ‘immature green’ was aided by application of 40 μl/liter of ethylene in a ripening room at 20°C. Tomatoes harvested at ‘breaker’ were more acceptable when ripe than all other maturities at harvest. Tomatoes harvested at ‘immature green’, ‘mature green’, ‘light pink’, and ‘light red’ were of similar sensory acceptability. The tomatoes harvested at ‘light pink’ and ‘light red’ when ripe were similar or lower in total soluble solids and generally lower in locular content compared to other harvest maturities. There was a high correlation between sensory scores for color and measured external and internal color.