Effect of foliar application of 2,4‐D and calcium on red‐skinned potato cultivars

Abstract

Applications of the plant growth regulator 2,4‐dichlorophenoxyacetic acid (2,4‐D) and calcium (Ca) are often used to improve the tuber skin quality of red potatoes. Field trials were conducted at Klamath Falls, OR in 2004 and 2005 to evaluate the effect of foliar applications of 2,4‐D and Ca on yield components, specific gravity, and the tuber skin color of four red‐skinned potato cultivars (Red LaSoda, Mazama, Cherry Red, and Rio Rojo). Skin color was evaluated using a Konica Minolta colorimeter at three‐time points during storage. Treatments of either 2,4‐D or Ca did not affect total tuber yield. However, 2,4‐D increased the proportion of tubers less than 170 g potato. When compared to non‐treated potato plants, 2,4‐D resulted in darker tuber skin with increased red pigmentation. Foliar application of Ca did not affect the tuber yield nor skin color. Calcium addition (in a form of CaCl2) decreased specific gravity possibly due to the chloride component. All potato cultivars exhibited color fading throughout the 6‐month storage period. Our data support the evidence that foliar application of 2,4‐D effectively enhances the color of most red‐skin potatoes, whereas foliar application of Ca may be not necessary in soils with adequate Ca supply.

A scalable, low-cost phenotyping strategy to assess tuber size, shape, and the colorimetric features of tuber skin and flesh in potato breeding populations

“…Much of our knowledge pertaining to the genetic basis of potato skin and flesh color has been ascertained from manual qualitative scoring of individual clones for their color characteristics (Salaman, 1910;Zhang et al, 2009), whereas visual inspection of skin quality and internal flesh color is an important component of tuber grading protocols. To date, most research studies have relied upon categorical scoring of skin and flesh color performed by human subjects (Buhrig et al, 2015;De Jong, 1987;Jung et al, 2009) or based upon subsampling within a single tuber using a digital colorimeter (Buhrig et al, 2015;Qin et al, 2020;Roe et al, 2014;Thornton et al, 2013;Waterer, 2010). These types of measurement strategies are subject to many of the challenges associated with manual measurements of tuber shape; particularly the tradeoffs observed between accuracy, precision, resolution, and throughput (Krupek et al, 2021;Miller et al, 2023;Roe et al, 2014).…”