Oranges looking better and better

Radiant skin sells oranges - just how many we should find out in winter, when this season’s navel oranges for export and domestic consumption mature.

That’s because more and more navel orange growers have adopted management practices recommended following a NSW DPI study into rind breakdown.

'The rind or skin of an export orange should be shiny-looking, firm, slightly light-orange in colour - with little scar or blemish,' said Steve Falivene, NSW DPI horticulturist based at Dareton.

'Growers exporting navels to the US found out the hard way a number of years ago about the importance of paying attention to rind quality,' he said.

'Rind breakdown in the export fruit cost the industry dearly with growers receiving bills instead of returns. The export fruit had to survive six to eight weeks via a sea voyage before they were sold from the shelves of US supermarkets.'

The industry approached NSW DPI researcher Dr Ken Bevington in collaboration with CSIRO researcher Michael Treeby to look into strategies to reduce rind breakdown of export fruit. One of the key strategies from the project is the use of gibberellic acid (GA) in delaying rind ageing and albedo breakdown.

Results of trials investigating the timing of summer GA applications confirmed the beneficial effects of the sprays in reducing rind breakdown and improving rind quality.

'GA application strategies and other key management practices for the December to March period have been taken to the industry which has responded with widespread adoption,' said Mr Falivene.

'As much as 85 per cent of growers are applying GA early in the season when fruit are golf ball sized in January.

'The January spray reduces the incidence of albedo breakdown and improves rind quality without delaying colour development.

'Growers have another option to apply a second GA spray in March or April when fruit are a green silver colour to delay the development of the rind.

'This means that the fruit will still be in good condition if harvested in the mid to latter stages of the season.'

Mr Falivene said the increased uptake of GA applications looks good for this year’s crop.

'All other things – such as weather conditions - being equal we are expecting to see good export quality oranges maturing in winter.'

Further information

Contact: Steve Falivene, NSW DPI, Dareton on (03) 5019 8405.