ST. LOUIS — Stronger sales of bioengineered corn, soybeans and cotton helped Monsanto Co. return to profitability in the fiscal first quarter of 2011. Net income in the quarter ended Nov. 30 totaled $6 million, equal to 1c per share on the common stock, up from a loss of $19 million in the same period a year ago. Net sales for the company totaled $1,830 million, up 8% from $1,697 million a year ago. Monsanto said revenue from seed sales rose 13% to $1,163 million. Sales of corn seeds and traits rose 8% to $614 million, while soybean revenue climbed 12% to $226 million, and vegetable revenue grew 6% to $183 million. Cotton revenue surged 90% to $112 million. Monsanto said it cut general and administrative expenses 9% after restructuring operations last year, and increased research and development spending 13%.