New Zealand had challenged the restrictions, which it said amounted to an effective ban on its fruit, arguing they were unscientific.
Victory for New Zealand would allow it to resume apple exports to its biggest trading partner and clear the way for sales to other markets where its fruit is banned.
New Zealand officials estimate that lifting the Australian ban could add NZ$30 million ($21 million) within two-three years to apple exports totaling NZ$400 million in 2009 - good news for New Zealand producers such as Turners & Growers.
Australia imposed the restrictions in 1921 to protect Australian apple trees from fire blight, a pest that also affects pear trees and rose bushes.
The government had said on Aug. 10 that it would appeal in order to protect Australian agriculture from health risks.
The WTO had been due to adopt the ruling, making it binding, at a meeting on Tuesday of its dispute settlement body, but the chairman of the body announced at the start of the meeting that Australia had confirmed its intention to appeal.
The WTO's appellate body now has 2-3 months to review the case.
