Abstract
Cultivars of tomato now in use are capable of tremedous marketably yields. Yields of machine harvested canning tomatoes in the near future will increase with no further advance in knowledge. Further gains are to be expected because of improvements that will come from regimens other than plant pathology and genetics. Higher potential yields of many prolific selections are not attainable because of lack of knowledge on how to deal with nutritional imbalances of tomato plants loaded with fruits.