* Executive sees capex this year down to 2.95 bln reais
* Second-quarter loss widened from a year earlier
SAO PAULO, Aug 8 (Reuters) - Cosan SA Industria e Comercio, Brazil's biggest sugar and ethanol producer, reducedits planned capital expenditures for 2013 by 150 million reais($65 million) the day after posting an unexpected net loss forthe second quarter.
Capex in 2013 will be 2.95 billion reais, rather than 3.2billion reais previously estimated, Marcelo Martins, head ofinvestor relations, said on a Thursday conference call.
The company attributed its second-quarter loss of 198million reais to the non-cash impact of a weaker local currencyon dollar-denominated debt.
Analysts in a Reuters poll had forecast an average profit of71 million reais. Cosan earned 30 million reais in the firstquarter and posted a net loss of 17.1 million reais in thesecond quarter of 2012.
Cosan is a partner with oil major Royal Dutch Shell in a fuel distribution and sugar venture called Raizen.
Martins said "only" 100,000 tonnes of the company's cane hadbeen damaged by the recent frost in southern Brazil, out of atotal 60 million tonnes expected from the 2013/14 crop.
Agriculture research company Datagro told Reuters theunusual weather had damaged nearly a fifth of Brazil'sunharvested center-south cane crop, which is expected to yield arecord 590 million tonnes.
Cosan's earnings before interest, taxes, depreciation andamortization, a closely watched measure of underlying profit,jumped to 381.6 million reais in the second quarter from 66.8million reais a year earlier.