title: Toward characterizing seed vigor in alfalfa through proteomic analysis of germination and priming.
abstract: Alfalfa, the most widely grown leguminous crop in the world, is generally exposed to severe salinity stress in Tunisia, notably affecting its germination performance. Toward a better understanding of alfalfa seed vigor, we have used proteomics to characterize protein changes occurring during germination and osmopriming, a pretreatment that accelerates germination and improves seedling uniformity particularly under stress conditions. The data revealed that germination was accompanied by dynamic changes of 79 proteins, which are mainly involved in protein metabolism, cell structure, metabolism, and defense. Comparative proteomic analysis also revealed 63 proteins specific to osmopriming, 65 proteins preferentially varying during germination, and 14 proteins common to both conditions. Thus, the present study unveiled the unexpected finding that osmopriming cannot simply be considered as an advance of germination-related processes but involves other mechanisms improving germination such as the mounting of defense mechanisms enabling osmoprimed seeds to surmount environmental stresses potentially occurring during germination. The present results therefore provide novel avenues toward understanding the mechanisms of invigoration of low vigor seeds by priming treatments that are widely used both in commercial applications and in developing countries (on farm seed priming) to better control crop yields.
authors.affiliation: Laboratoire de Biologie et Physiologie Cellulaire Végétales, Département de Biologie, Université de Tunis, Tunisie. yacoubirafika@yahoo.fr
authors.forename: Rafika
authors.initials: R
authors.lastname: Yacoubi
authors.forename: Claudette
authors.initials: C
authors.lastname: Job
authors.forename: Maya
authors.initials: M
authors.lastname: Belghazi
authors.forename: Wided
authors.initials: W
authors.lastname: Chaibi
authors.forename: Dominique
authors.initials: D
authors.lastname: Job
mesh_terms: D015180:Electrophoresis, Gel, Two-Dimensional; D018525:Germination / Q000187:drug effects; D000455:Medicago sativa / Q000737:chemistry / Q000378:metabolism*; D010940:Plant Proteins / Q000032:analysis* / Q000378:metabolism; D011092:Polyethylene Glycols; D020543:Proteome / Q000032:analysis / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D036226:Seedlings / Q000378:metabolism; D012639:Seeds / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological
chemical_list: D010940:Plant Proteins; D020543:Proteome; D011092:Polyethylene Glycols; D012965:Sodium Chloride