Bunge Ltd., a premier producer of fertilizer and soybean-based foods, has agreed to buy Westchester-based Corn Products International in an all stock deal worth $4.4 billion to gain access to its line of starches and sweeteners.   The sale "provides a unique opportunity for Bunge to establish an integrated, global presence in the corn value chain, which is highly complementary to our existing operations," Bunge Chairman Alberto Weisser said Monday.

