Dow Chemical Co (DOW.N) has struck a deal to sell a part of its global herbicide business, as low crop prices continue to drive talk of consolidation in the agriculture industry. Dow on Monday said it agreed to sell a portfolio of weed killers known as dinitroanilines to privately held Gowan Company. The deal comes a month after Dow said it was reviewing all options for its farm chemicals and seeds unit, which has reported falling sales for nearly a year.