Raman spectroscopy detects chemical differences between potato tubers produced under normal and heat stress growing conditions

Abstract

Potato is the most consumed vegetable worldwide. Potato tubers contain water, starch, proteins, minerals, and vitamins. The amounts of these chemicals depend on the cultivar and growing location. When potatoes are exposed to high temperatures during the growing period, tuber yield and quality are detrimentally affected; however, there is limited knowledge about the influence of high temperatures on tuber chemical composition. With temperatures rising around the globe, the reaction of potato cultivars to high temperatures is increasingly important, and heat-induced changes, including changes in the chemical composition of tubers, should be considered. The Texas A&M University Potato Breeding Program has been selecting potato clones under high-temperature conditions for many years. Several released cultivars are considered heat-tolerant based on high marketable yields and low internal and external tuber defects. In this study, we used Raman spectroscopy (RS), an analytical tool, to determine whether heat stress causes changes in the chemical composition of tubers of ten potato cultivars. RS is a non-invasive method that requires less time and labor than conventional chemical analysis. We found drastic changes in the intensities of vibrational bands that originate from carbohydrates in the spectra acquired from tubers of heat-stressed plants compared to tubers produced by potato plants grown under normal conditions. These results demonstrate that RS could be used as a replacement or complement to conventional chemical analysis to inspect the effect of heat stress on tuber chemical composition.

Assessing heat tolerance in potatoes: Responses to stressful Texas field locations and controlled contrasting greenhouse conditions

“…Results from greenhouse trials for studying the effects of normal vs. heat stress conditions on specific gravity and tuber dry matter of potato clones have been previously reported ( Gautam et al., 2023 ). Results showed that clones and growing conditions were major factors affecting the phenotypic variation for both traits ( Supplementary Figure 4 ), with heat stress conditions resulting in lower specific gravity and tuber dry matter than normal conditions.…”

Genetic architecture of tuber-bound free amino acids in potato and effect of growing environment on the amino acid content

“…The Springlake location regularly has higher night temperatures (often > 20 °C near harvest), resulting in lower marketable yield and more external and internal tuber defects as result of having more heat stress than the Dalhart location. Experiments under controlled greenhouse conditions showed that heat stress-induced chemical changes in potato tubers 78 . Proline is crucial for plant growth and differentiation throughout the whole life cycle and also serves as a superior osmolyte and also performs three other crucial functions under stress, including metal chelation, antioxidant defense, and signaling 79 .…”

Genetic Basis of Potato Tuber Defects and Identification of Heat-Tolerant Clones

“…Heat stress during the potato growing season is a major environmental factor that adversely affects the growth, development, and productivity of potatoes ( Solanum tuberosum ), which is one of the most important staple crops in the world [ 1 , 2 ]. The effects of heat stress on potato crops have been linked with external and internal tuber defects [ 1 , 3 ].…”

“…External and internal tuber abnormalities significantly affect the marketability of potato tubers [ 3 ]. External and internal tuber defects are also accompanied by quality deterioration with reduction in specific gravity resulting in lower tuber dry matter and an increase in reducing sugars [ 2 ]. Tuber quality deterioration causes huge economic losses to growers and processors.…”