Effects of repeated replanting on yield, dry matter, starch, and protein content in different potato (Solanum tuberosum L.) genotypes

Abstract

This investigation scrutinized the yield, starch, and protein content of five distinct potato genotypes (Desiree, Borostyán, Piroska, Rubinka, and Rózsa) over 5 years of repetitive replanting. The experiment aimed to compare different potato genotypes and examine the yield reduction resulting from possible genetic deterioration over the years. The research took place in Zirc, Hungary’s temperate deciduous forest zone, at 450 m elevation from 2017 to 2021, on a 100 m2 plot. Potato dry matter was measured according to MSZ 6369-4:1987, and starch content followed MSZ 6830-18:1988 standards. Tubers’ total nitrogen was gauged using the Kjeldahl method, while crude protein analysis employed the Dumas method. Pure protein evaluation adhered to the trichloroacetic acid precipitation technique, all consistent with WBSE-131:2018. Observed variations in starch content revealed Borostyán as the genotype with the highest mean starch content (75.41%) and Desiree with the least (74.98%). Protein content also varied among the genotypes; Borostyán exhibited the highest average level (10.99%), while Desiree had the least (5.52%). The remaining genotypes, Piroska, Rubinka, and Rózsa, exhibited comparable mean protein levels between 8.15 and 8.82%. Findings also noted a positive correlation between yield and starch and protein content. However, certain genotypes demonstrated a negative correlation, highlighting the impact of genetic factors and management practices such as nitrogenous fertilization and crop rotation on these associations. Additionally, the findings suggest that not only the standard Desiree variety but also the Borostyán variety can be reliably recommended for use in potato research and breeding initiatives. Conclusively, this study provides insights valuable for potato breeding and selection programs and the potential development of high-protein potato products. Further investigation is recommended to elucidate the mechanisms and genetic determinants that impact these observed relationships.