* Net revenue edges up 0.2 pct, Assaí surges 27.8 pct
* Supermarkets, appliance sales fall from year ago
* Cnova probe calls for provision from inventory issues (Adds share performance, details of sales data)
By Brad Haynes
SAO PAULO, Jan 12 (Reuters) - GPA SA, Brazil's biggest retailer, reported flat fourth-quarter sales on Tuesday as robust growth at its wholesale unit offset weaker supermarket and appliance sales, sending shares sliding to a six-year low.
Consolidated net revenue edged up 0.2 percent from a year earlier to 19.710 billion reais ($4.88 billion), it said in a securities filing, boosted by a 27.8 percent jump in the fast-growing Assaí wholesale chain.
Revenue from its food retailers Extra and Pão de Açucar slipped 0.3 percent, while the top line of home furnishings division Via Varejo SA tumbled 14.7 percent and online retailer Cnova NV rose 9.5 percent.
Consumer prices climbed 10.7 percent last year, according to Brazil's benchmark IPCA index, hurting household demand along with rising unemployment and tighter credit amid the worst economic recession since 1990.
GPA shares fell as much as 3.6 percent on Tuesday to 35.46 reais, their lowest since July 2009 and far from the high of 100 reais in May. GPA is controlled by France's Casino Guichard Perrachon SA.
Sales at GPA stores open at least 12 months fell a consolidated 2.3 percent for the group, driven by the 15.2 percent drop for Via Varejo.
In a separate filing, GPA updated its Cnova investigation begun Dec. 18 into irregular inventory management at its Brazilian distribution centers.
External legal and accounting experts leading the probe found that Cnova's net sales may have been overestimated by about 110 million reais. The review also found returned and damaged items made up about 10 percent of inventory, with a substantial impact on accounts receivable, according to the filing.
As a result, investigators recommended Cnova make preliminary provisions to reflect an impact of 110 million to 130 million reais on earnings before interest and taxes, without immediate cash effects.
Cnova also found about 70 million reais in additional accounts payable to suppliers that is also expected to trigger a provision. Changes to inventory accounting at Cnova may generate a further writedown of 10 million euros ($11 million).
GPA plans to report full fourth-quarter results on Feb. 24, pending publication of Cnova's results, which are subject to the ongoing investigation. ($1 = 4.04 reais) ($1 = 0.92 euros) (Additional reporting by Guillermo Parra-Bernal and Priscila Jordão; Editing by Jeffrrey Benkoe)