title: The effect of plant growth regulators, nitric oxide, nitrate, nitrite and light on the germination of dimorphic seeds of Suaeda salsa under saline conditions.
abstract: Suaeda salsa, a leaf succulent shrub in the family Chenopodiaceae, is one of the most important halophytes in China. Suaeda salsa produces dimorphic seeds (soft brown seeds and hard black seeds). Seeds of S. salsa were collected from the coastal salt flats near Huanghua City, China. Experiments were conducted to determine the salinity-alleviating effect of plant growth regulators, nitric oxide, nitrate, nitrite and light on the germination of dimorphic seeds of S. salsa. Brown seeds had a higher germination rate than black seeds in all experiments. Black seeds were more sensitive to salt in the absence of light in comparison to brown seeds. Brown seeds absorbed water more quickly in comparison to black seeds and were found to be more tolerant of salt stress. Our results showed that 1-aminocyclopropane-1-carboxylate (ACC, the immediate precursor of ethylene), nitrite, GA(4) and BA improved seed germination in the presence of salt. However, nitrate, GA(1), GA(3) failed to alleviate salt stress. ABA inhibited seed germination and seedling growth. Possible mechanisms involved in the alleviation of salt stress in S. salsa seeds and the ecological adaptation of the seeds to the environment are discussed.
authors.affiliation: Shijiazhuang Institute of Agricultural Modernization, Chinese Academy of Science, Shijiazhuang Hebei Province, The People's Republic of China, wqli@ms.sjziam.ac.cn
authors.forename: Weiqiang
authors.initials: W
authors.lastname: Li
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Liu
authors.forename: M
authors.initials: M
authors.lastname: Ajmal Khan
authors.forename: Shinjiro
authors.initials: S
authors.lastname: Yamaguchi
mesh_terms: D019663:Chenopodiaceae / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D004305:Dose-Response Relationship, Drug; D018525:Germination / Q000187:drug effects / Q000502:physiology*; D008027:Light; D009566:Nitrates / Q000494:pharmacology; D009569:Nitric Oxide / Q000494:pharmacology; D009573:Nitrites / Q000494:pharmacology; D017672:Nitrogen Compounds / Q000494:pharmacology*; D010937:Plant Growth Regulators / Q000494:pharmacology*; D012639:Seeds / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D012965:Sodium Chloride / Q000494:pharmacology*; D012987:Soil / Q000032:analysis; D013997:Time Factors; D014867:Water
chemical_list: D009566:Nitrates; D009573:Nitrites; D017672:Nitrogen Compounds; D010937:Plant Growth Regulators; D012987:Soil; D014867:Water; D009569:Nitric Oxide; D012965:Sodium Chloride