Growth and postharvest performance of white radish (Raphanus sativus L.)

The growth and postharvest performance of 4 cultivars of white radish, or 'daikon' (Raphanus sativus L. Longipinnatus group), 'Fukumi', 'Tomas', 'Oshin' and 'Long White' were compared over 2 growing seasons in New South Wales, Australia. The first 3 cultivars are considered promising for a proposed export industry and the fourth, 'Long White', is a standard cultivar already used commercially. Preferred market weight (1000 g) was reached in 60 days in the spring-summer trial and 82-85 days in the autumn-winter trial. Postharvest life was limited mainly by the physiological disorder 'pithiness'. Pithiness is characterised by the formation of air spaces in the root, which will eventually leave it spongy, dry and hollow. It developed both in the field and in storage, especially in 'Long White'. There was slightly less pithiness in all cultivars in the cooler season autumn trial, but the development of pithiness was highly related to cultivar. Pithiness was not related to senescence, since it developed in the field in 'Long White' from an early stage of growth. 'Tomas' was the best cultivar overall, and market quality was maintained for a simulated export period of 4 weeks, provided it was harvested at the preferred market weight of 1000 g. All leaf material should be trimmed from the radishes before storage.