The rate and amount of absorption of maleic hydrazide by potato tubers

Summary

Sebago and Huron potatoes were given a foliar spray of 2500 ppm MH Amine three weeks past full bloom. Sufficient absorption occurred within a 24 hour interval (six ppm residue) to satisfactorily inhibit sprouting of tubers stored six months at 50 F. A more complete inhibition of sprouting was attained following a 48 hour absorption period (17 ppm residue) with the exception of a few tubers with long sprouts which occurred at random. Sprouting was stimulated under conditions of slight absorption (two to four hours and four ppm residue). Residue levels of the Sebago variety continued to increase from six ppm after 24 hours of absorption to a maximum of 36 ppm at the end of seven days, despite very heavy rain on the third and fourth days. Approximately 60 hours were required to attain a 50% level of absorption.