title: Assessment of the physiological responses to drought in different sugar beet genotypes in connection with their genetic distance.
abstract: Drought affects many physiological processes, which influences plant productivity. The aim of this study was to evaluate the degree of genotypic diversity in drought tolerance of sugar beet genotypes (Beta vulgaris L.) in connection with their genetic distance. Three hybrid genotypes produced by crossing double haploid genotype (P-pollinator) with cytoplasmic male-sterile female part (MS), as well as with two parent lines, were examined. Drought conditions were imposed by the cessation of watering at the 3-4 leaf stage for about three months, after which irrigation was resumed. Control plants were optimally irrigated throughout the entire vegetation period. Long-term drought significantly increased the wilting of leaves (Wilt.), specific leaf weight (SLW), the succulence index (Suc.I), leaf senescence and membrane damage (El-l). Simultaneously, the osmotic potential (ψs), leaf area index (LAI), absorption of photosynthetic active radiation (PAR) and the efficiency of the photosynthetic apparatus (Φ PSII) declined under water deficit conditions. The examined genotypes demonstrated a clear diversity in their physiological response to drought. Based on these findings, we suggest that traits that are strongly correlated with root and sugar yield, e.g. Φ PSII, LAI, PAR absorption and ψs, could be used as potential selection criteria in physiological-associated breeding strategies to improve drought tolerance in sugar beet. There was not a significant correlation between the genetic distance separating different sugar beet genotypes and the observed heterotic effect of root or sugar yields, with the exception of heterosis of root yield under optimal conditions, where the correlation was negative.
authors.affiliation: Department of Plant Physiology, Faculty of Agriculture and Biology, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland.
authors.forename: Danuta
authors.initials: D
authors.lastname: Chołuj
authors.affiliation: Department of Plant Physiology, Faculty of Agriculture and Biology, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland. Electronic address: anita_wisniewska@sggw.pl.
authors.forename: Anita
authors.initials: A
authors.lastname: Wiśniewska
authors.affiliation: UPMC Université Paris 6, UMR7208 Laboratoire Biologie des Organismes Aquatiques et Ecosystèmes (UPMC CNRS MNHM IRD UCAEN), Bâtiment A, 7, quai St. Bernard, 75005 Paris, France.
authors.forename: Kamil M
authors.initials: KM
authors.lastname: Szafrański
authors.affiliation: Department of Plant Physiology, Faculty of Biology and Biotechnology, Ruhr-University Bochum, ND Nord 2/33, Universitätsstraße 150, 44801 Bochum, Germany.
authors.forename: Justyna
authors.initials: J
authors.lastname: Cebula
authors.affiliation: Department of Experimental Design and Bioinformatics, Faculty of Agriculture and Biology, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland.
authors.forename: Dariusz
authors.initials: D
authors.lastname: Gozdowski
authors.affiliation: Department of Plant Physiology, Faculty of Agriculture and Biology, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland.
authors.forename: Sławomir
authors.initials: S
authors.lastname: Podlaski
mesh_terms: D027461:Beta vulgaris / Q000033:anatomy & histology / Q000235:genetics / Q000502:physiology*; D050260:Carbohydrate Metabolism / Q000235:genetics; D003890:Desiccation; D055864:Droughts; D014644:Genetic Variation; D006823:Hybrid Vigor; D018517:Plant Roots / Q000378:metabolism; D019105:Random Amplified Polymorphic DNA Technique
keywords: Drought tolerance; Genetic variation and distance; Physiological traits; Selection criteria; Sugar beet