Influence of 'Atlantic' and 'Dakota Pearl' Mother Plants Exposed to Sublethal Glyphosate and Dicamba on Daughter Plants

Abstract

The increased use of dicamba and glyphosate-tolerant soybean (Glycine max L.) may result in off-target exposure and damage to nearby seed potato (Solanum tuberosum L.) plants. If daughter tubers from herbicide-exposed mother plants are used for seed the following year, daughter plant growth and production may be influenced by the herbicides carried over in the tubers used as seed. The objective of this study was to determine the effects from 'Atlantic' and 'Dakota Pearl' mother plants that were exposed to glyphosate, dicamba, or the combination of glyphosate and dicamba the previous year at the tuber initiation stage on daughter tubers planted as seed. Daughter plants from mother plants that were sprayed with glyphosate at 197 g ha⁻¹ or the combination of glyphosate at 197 g ha⁻¹ and dicamba at 99 g ha⁻¹ had delayed emergence at eight weeks after planting, shorter plants from five to nine weeks after planting, and lower total yield when compared to the non-treated. Daughter plants from mother plants that were sprayed with glyphosate at 197 g ha⁻¹ had the lowest marketable yield, which was less than all other treatments except when daughter plants were from mother plants that were sprayed with the combination of glyphosate at 197 g ha⁻¹ and dicamba at 99 g ha⁻¹. The two chipping cultivars differed in response for plant emergence at five, six, and seven weeks after planting and for canopy development eight weeks after planting. Results suggested that sublethal exposure of glyphosate and dicamba to chipping seed potatoes (mother plants) at the tuber initiation stage the previous year, can influence the growth and development of daughter plants to affect total and marketable yield.