C Julian1, J Rodrigo, M Herrero. 1. Unidad de Fruticultura, Centro de Investigación y Tecnología Agroalimentaria de Aragón, Av. Montañana 930, 50059 Zaragoza, Spain.
Abstract
BACKGROUND AND AIMS: In temperate woody perennials, flower bud development is halted during the winter, when the buds enter dormancy. This dormant period is a prerequisite for adequate flowering, is genetically regulated, and plays a clear role in possibly adapting species and cultivars to climatic areas. However, information on the biological events underpinning dormancy is lacking. Stamen development, with clear differentiated stages, appears as a good framework to put dormancy in a developmental context. Here, stamen developmental changes are characterized in apricot (Prunus armeniaca) and are related to dormancy. METHODS: Stamen development was characterized cytochemically from the end of August to March, over 4 years. Developmental changes were related to dormancy, using the existing empirical information on chilling requirements. KEY RESULTS: Stamen development continued during the autumn, and the flower buds entered dormancy with a fully developed sporogenous tissue. Although no anatomical changes were observed during dormancy, breaking of dormancy occurred following a clear sequence of events. Starch accumulated in particular places, pre-empting further development in those areas. Vascular bundles developed and pollen mother cells underwent meiosis followed by microspore development. CONCLUSIONS: Dormancy appears to mark a boundary between the development of the sporogenous tissue and the occurrence of meiosis for further microspore development. Breaking of dormancy occurs following a clear sequence of events, providing a developmental context in which to study winter dormancy and to evaluate differences in chilling requirements among genotypes.
BACKGROUND AND AIMS: In temperate woody perennials, flower bud development is halted during the winter, when the buds enter dormancy. This dormant period is a prerequisite for adequate flowering, is genetically regulated, and plays a clear role in possibly adapting species and cultivars to climatic areas. However, information on the biological events underpinning dormancy is lacking. Stamen development, with clear differentiated stages, appears as a good framework to put dormancy in a developmental context. Here, stamen developmental changes are characterized in apricot (Prunus armeniaca) and are related to dormancy. METHODS: Stamen development was characterized cytochemically from the end of August to March, over 4 years. Developmental changes were related to dormancy, using the existing empirical information on chilling requirements. KEY RESULTS: Stamen development continued during the autumn, and the flower buds entered dormancy with a fully developed sporogenous tissue. Although no anatomical changes were observed during dormancy, breaking of dormancy occurred following a clear sequence of events. Starch accumulated in particular places, pre-empting further development in those areas. Vascular bundles developed and pollen mother cells underwent meiosis followed by microspore development. CONCLUSIONS: Dormancy appears to mark a boundary between the development of the sporogenous tissue and the occurrence of meiosis for further microspore development. Breaking of dormancy occurs following a clear sequence of events, providing a developmental context in which to study winter dormancy and to evaluate differences in chilling requirements among genotypes.
Authors: Nathalie Druart; Annika Johansson; Kyoko Baba; Jarmo Schrader; Andreas Sjödin; Rupali R Bhalerao; Lars Resman; Johan Trygg; Thomas Moritz; Rishikesh P Bhalerao Journal: Plant J Date: 2007-04-05 Impact factor: 6.417
Authors: Olga E Mirgorodskaya; Nuria K Koteyeva; Alexandra V Volchanskaya; Evgeny A Miroslavov Journal: Protoplasma Date: 2015-02-03 Impact factor: 3.356
Authors: Hong Zhu; Pao-Yang Chen; Silin Zhong; Chris Dardick; Ann Callahan; Yong-Qiang An; Steve van Knocker; Yingzhen Yang; Gan-Yuan Zhong; Albert Abbott; Zongrang Liu Journal: Hortic Res Date: 2020-08-01 Impact factor: 6.793
Authors: Hong Zhu; Pao-Yang Chen; Silin Zhong; Chris Dardick; Ann Callahan; Yong-Qiang An; Steve van Knocker; Yingzhen Yang; Gan-Yuan Zhong; Albert Abbott; Zongrang Liu Journal: Hortic Res Date: 2020-08-01 Impact factor: 6.793