In a 4-quart pot combine 1 3/4 cup water with 1 cup wild rice. Cover and bring to boil. Once boiling, reduce heat to a simmer and simmer for 45 minutes or until all the water has evaporated. Remove from heat, fluff with a fork, and let cool.
While rice is cooking, preheat oven to broil and move your baking rack to the top. Brush corn cobs and zucchini slices with olive oil. Broil corn for about 15 minutes, rotating often. Once cooked, remove from oven and let cool.
While corn and zucchini cook, combine the ingredients for the basil pesto in a blender and set aside.
To assemble the mason jar salads, place a layer of pistachios at the bottom of (2) one-quart mason jars or (4) 1/2 quart jars. Top with tomatoes, corn, zucchini, wild rice, and watercress, in that order. Refrigerate until ready to go.