title: Phytohormone and assimilate profiles in emasculated flowers of the black locust (Robinia pseudoacacia) during development.
abstract: Emasculation and bagging of flowers, which are widely used in the controlled pollination of monoclinous plants, may induce premature senescence, flower abscission and low fruit set. To determine the mechanism responsible for these phenomena, levels of abscisic acid (ABA), jasmonic acid (JA), indole-3-acetic acid (IAA), ethylene, soluble sugars, reducing sugars and free amino acids in black locust (Robinia pseudoacacia) flowers subjected to different treatments were quantified at different developmental stages. The phytohormones and assimilates were also quantified in untreated flowers to investigate the presence of discernible patterns. The levels of ethylene and ABA in emasculated and bagged (EB) flowers increased prematurely compared with those of untreated flowers, whereas the content of reducing sugars in EB flowers decreased compared with that of untreated flowers. These results indicated that the premature increase in ethylene and ABA synthesis, and the decrease in reducing sugars content, in EB flowers may cause flower abscission and result in low fruit set, which may be relevant for assimilate applications and future research on the regulation of controlled pollinations with exogenous phytohormones.
authors.affiliation: Beijing Forestry University National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of the Ministry of Education, College of Biological Sciences and Technology No. 35 Qinghua East Road, Haidian District Beijing 100083 China.
authors.forename: Peng
authors.initials: P
authors.lastname: Sun
authors.forename: Cunquan
authors.initials: C
authors.lastname: Yuan
authors.forename: Li
authors.initials: L
authors.lastname: Dai
authors.forename: Yang
authors.initials: Y
authors.lastname: Xi
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Li
authors.forename: Ruiyang
authors.initials: R
authors.lastname: Hu
authors.forename: Yuhan
authors.initials: Y
authors.lastname: Sun
authors.forename: Zhaohe
authors.initials: Z
authors.lastname: Xu
authors.forename: Yun
authors.initials: Y
authors.lastname: Li
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D001901:Botany / Q000379:methods; D003517:Cyclopentanes / Q000378:metabolism; D005030:Ethylenes / Q000378:metabolism; D035264:Flowers / Q000254:growth & development / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism; D054883:Oxylipins / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism*; D031301:Robinia / Q000254:growth & development / Q000378:metabolism*
chemical_list: D003517:Cyclopentanes; D005030:Ethylenes; D007210:Indoleacetic Acids; D054883:Oxylipins; D010937:Plant Growth Regulators; C011006:jasmonic acid; C030737:indoleacetic acid; D000040:Abscisic Acid; C036216:ethylene