Growers apply lots of Mancozeb which is manganese. This tells me that the monosaccharides (glucose and fructose) are not being converted to disaccharides (sucrose) which is an indicator of manganese deficiency. Lots of botrytis in wine grapes there, as well.. The carbohydrate source for botrytis is monosaccharides so lots of Mancozeb there, too. Can we get to 100% control? What do the growers in the humid South do to survive?