Foliar‐Applied Daminozide Effect on the Yield and Tuber Size Distribution of Potato

Abstract

AbstractThis study investigated the effects of foliar applied daminozide (butanedioic acid mono 2, 2‐dimethyl hydrazide, Alar 85, Uniroyal Chemical, Inc.) on two potato (Solanum tuberosum L.) cultivars, Kennebec and Red Pontiac, field grown with six replications over 3 yr at Charlottetown, Prince Edward Island, Canada. Four treatments were evaluated in 1985: (i) control, (ii) 0.42 kg daminozide ha−1 applied when largest tubers reached 20 mm, and (iii) 0.85 kg daminozide ha ' applied when largest tubers reached either 20‐min or (iv) 30‐mm stage. The treatments evaluated in 1986 and 1987 were: (i) control, and (ii) 0.85 kg daminozide ha−1 applied when the largest tubers had reached either the 10‐mm, (iii) 20‐mm, or (iv) 30‐mm stage. Daminozide did not significantly affect foliar or tuber disease levels, nor total tuber yield, but an increase of 2.36 t ha−1 in the seed size tuber yield did result from a 0.85 kg daminozide ha−1 application at the 30‐mm tuber size stage. Differences in cultivar responses occurred at earlier tuber size stages. Application of daminozide modified the tuber size distribution of the potato crop, however considering the cost of daminozide, its potential value to seed potato producers is questionable.