When Geoffrey von Maltzahn was first pitching farmers to try out his startup\u2019s special seeds, he sometimes told them, half-acknowledging his own hyperbole, that \u201cif we\u2019re right, you shouldn\u2019t just see results in the field, you should be able to see them from outer space.\u201d As the co-founder of a company called Indigo Ag, von Maltzahn was hawking a probiotic that he hoped would increase their crop yields dramatically.