* Corn near 1-week high on strong Chinese demand for U.S. supplies * Chicago wheat futures up for 3rd session, soybeans ease (Adds comment in paragraph 3, details on threat from armyworm in China) SINGAPORE, March 17 (Reuters) - Chicago corn futures gained for a fifth consecutive session on Wednesday as China’s strong purchases of U.S. supplies underpinned the market. Wheat prices rose for a third straight session while soybeans ticked lower. “News of a hefty U.S. export sale to China was a plus,” said Tobin Gorey, director of agricultural strategy, Commonwealth Bank of Australia. The most-active corn contract on the Chicago Board Of Trade (CBOT) added 0.1% to $5.55 a bushel as of 0332 GMT, after gaining 0.9% on Tuesday. Soybeans were down 0.2% at $14.20-3/4 a bushel and wheat gained 0.1% to $6.47-3/4 a bushel. The U.S. Department of Agriculture (USDA) on Tuesday confirmed U.S. corn sales to China totalling 1.156 million tonnes, the highest since January. The sales came after the USDA on Monday reported one of the strongest weeks of corn export inspections on record. There could be more demand for corn imports as China faces a threat from armyworm, which attack corn among other crops. Pressure to prevent and control armyworm in China this year is significantly higher than last year, the country’s agriculture ministry said on Tuesday. The climate conditions in Mekong river area is favourable for reproduction of the pest, and there will be sufficient armyworm to migrate to China later, the Ministry of Agriculture and Rural Affairs said in a statement, citing Wu Kongming, an expert with the Chinese Academy of Agricultural Sciences. Russia is prepared to stop interfering in the regulation of grain exports when the market stabilises, the Interfax news agency cited Agriculture Minister Dmitry Patrushev as saying on Tuesday. Commodity funds were net buyers of CBOT corn, wheat and soybean futures contracts on Tuesday, net sellers of soymeal futures and net even in soyoil, traders said. (Reporting by Naveen Thukral; Editing by Devika Syamnath)