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More integrated evaluation of cold chain performance is key for developing a more resourceefficient, energy-smart food supply chain. The present study applies this rationale to evaluate the ambient loading protocol for overseas export of citrus fruit in refrigerated containers. Ambient loading implies that fruit, packed into ventilated boxes, are directly precooled in the container. This technique provides several economic and logistical advantages but is particularly challenging for phytosanitary cold disinfestation treatments. For such an integral approach, multiple relevant product and process parameters were monitored throughout the cold chain, such as fruit cooling rate, quality parameters, shelf life, pest disinfestation efficacy, and their spatial uniformity throughout the cargo load. Also energy consumption of the refrigeration unit was measured. The performance of the standard ambient loading practice was compared to two novel airflow strategies: the channelling configuration, which reduced airflow bypass between pallets, and the horizontal configuration, which forced air horizontally through the pallets. Standard ambient loading was able to cool the produce within about 3 d to the seven-eighths cooling time. The channelling configuration exhibited similar cooling behaviour but the fruit lost less moisture, lasted longer in shelf life conditions and had a better quality. The horizontal configuration performed worse on all aspects. The cooling performance of the container clearly depended on the way in which it was stowed and convectively cooled. This more holistic evaluation of the cooling strategy unveiled several trade-offs and allowed a multi-parameter evaluation of technological improvements to cold chain practices.

A survey of occurrence of entomopathogenic fungi was undertaken on soils from citrus orchards and refugia on conventionally and organically managed farms in the Eastern Cape Province in South Africa. An adapted method for baiting soil samples with key citrus pest Thaumatotibia leucotreta (Meyrick; Lepidoptera: Tortricidae) and Ceratitis capitata (Wiedemann; Diptera: Tephritidae) larvae, as well as with the standard bait insect, Galleria mellonella (Linnaeus; Lepidoptera: Pyralidae), was implemented. Sixty-two potentially useful entomopathogenic fungal isolates belonging to four genera were collected from 288 soil samples, an occurrence frequency of 21.53%. The most frequently isolated entomopathogenic fungal species was Beauveria bassiana (Balsamo) Vuillemin (15.63%), followed by Metarhizium anisopliae var. anisopliae (Metschnikoff) Sorokin (3.82%). Galleria mellonella was the most effective bait insect used to isolate fungal species (v 2 = 40.13, df = 2, P B 0.005), with a total of 45 isolates obtained, followed by C. capitata with 11 isolates, and T. leucotreta with six isolates recovered. There was a significantly (v 2 = 11.65, df = 1, P B 0.005) higher occurrence of entomopathogenic fungi in soil samples taken from refugia compared to cultivated orchards of both organically and conventionally managed farms. No significant differences were observed in the recovery of fungal isolates when soil samples from both farming systems were compared.

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