Konjac and general taro is not a plant, general taro is only used for general consumption, taro taste soft, sweet and glutinous, nutritional value similar to potatoes, and does not contain lobelia, easy to digest and does not cause poisoning, is a good alkaline food.

And the konjac plant poisonous, can not be directly eaten, need to be processed to eat, by a plant called konjac ground into powder produced, can also be used for industrial purposes. Konjac has "to intestinal sand" known. Konjac grows in the sparse forests, is a beneficial alkaline food, for people who eat too much animal acidic food, with eating konjac, can achieve food acid, alkaline balance. The picture is konjac root:

Taro, also known as taro, for the Tennessee family of perennial herbaceous plants taro underground fleshy bulb. Taro taste fine and soft, sweet and sticky, nutritional value is similar to potatoes, and does not contain lobelia, easy to digest without causing poisoning. Is a good alkaline food. Taro can be steamed or boiled, but must be thoroughly steamed or boiled.

Konjac is poisonous throughout the plant, to the tuber for the most, can not be eaten raw, need to be processed before eating. Poisoning tongue, throat burning, itching, swelling. Folk with vinegar with a little ginger juice, internal or containing cough, can be rescued. Konjac underground tuber is oblate, large, petiole stout, cylindrical, light green, with dark purple spots, palmate compound leaves, the inside is white.

Reference:

Konjac Baidu Encyclopedia