@article{ChmielewskiBaldermannGoetzetal.2018,
  author    = {Chmielewski, Frank M. and Baldermann, Susanne and G{\"o}tz, Klaus Peter and Homann, Thomas and G{\"o}deke, Kristin and Schumacher, Fabian and Huschek, Gerd and Rawel, Harshadrai Manilal},
  title     = {Abscisic acid related metabolites in sweet cherry buds (Prunus avium L.)},
  series = {Journal of Horticulture},
  volume    = {5},
  journal   = {Journal of Horticulture},
  number    = {1},
  issn      = {2376-0354},
  doi       = {10.4172/2376-0354.1000221},
  pages     = {221},
  year      = {2018},
  abstract  = {As our climate changes, plant mechanisms involved for dormancy release become increasingly important for commercial orchards. It is generally believed that abscisic acid (ABA) is a key hormone that responds to various environmental stresses which affects bud dormancy. For this reason, a multi-year study was initiated to obtain data on plant metabolites during winter rest and ontogenetic development in sweet cherry buds (Prunus avium L.). In this paper, we report on metabolites involved in ABA synthesis and catabolism and its effect on bud dormancy in the years 2014/15-2016/17. In previous work, the timings of the different phases of para-, endo-, ecodormancy and ontogenetic development for cherry flower buds of the cultivar 'Summit' were determined, based on classical climate chamber experiments and changes in the bud's water content. Based on these time phases, we focused now on the different aspects of the ABA-metabolism. The results show that there is a continual synthesis of ABA about 5 weeks before leaf fall, and a degradation of ABA during ecodormancy and bud development until the phenological stage 'open cluster'. This is confirmed by relating the ABA content to that of the total precursor carotenoids, neoxanthin and violaxanthin. The tentative monitoring of individual intermediate metabolites revealed that dihydroxyphaseic acid is the most abundant catabolite of ABA and ABA glucosyl ester is in terms of mass intensity, the most abundant ABA metabolite observed in this study. The results suggest that the direct route for ABA biosynthesis from farnesyl pyrophosphate may also be relevant in cherry flower buds.},
  language  = {de}
}
@article{ChmielewskiGoetzHomannetal.2017,
  author    = {Chmielewski, Frank M. and G{\"o}tz, Klaus-Peter and Homann, Thomas and Rawel, Harshadrai Manilal},
  title     = {Identification of Endodormancy Release for Cherries (Prunus Avium L.) by Abscisic Acid and Sugars},
  series = {Journal of Horticulture},
  volume    = {4},
  journal   = {Journal of Horticulture},
  number    = {3},
  issn      = {2376-0354},
  doi       = {10.4172/2376-0354.1000210},
  pages     = {9},
  year      = {2017},
  abstract  = {In order to develop reliable and physiologically sound models for the plant development in spring, the date of endodormancy release is always a crucial and mostly unknown model parameter. Until present, classical approaches - such as climate chamber experiments - are used to derive this unknown parameter. In these experiments, progressive plant development or significant changes in bud's fresh weight or water content are measurable markers for dormancy release. This study presents an alternative approach, which is based on four well-known metabolites. For 5 seasons (2011/12-2015/16), the content of abscisic acid (ABA) and sugars such as fructose, sucrose and glucose in sweet cherry flower buds (cultivar 'Summit') were weekly analysed between beginning of October and April. These data allow comparing the annual course of these metabolites with the date of endodormancy release, derived from a classical climate chamber experiment, published in a previous study. Results showed that ABA and sucrose are two important metabolites which can help to identify the date of endodormancy release of sweet cherries. On average, ABA content reached a plateau of 5.65 μg g-1 DW-1 during endodormancy, which was maintained for 3-6 weeks. The significant reduction of the ABA content after this period to 4.41 μg g-1 DW-1 on average during ecodormancy was nearly in agreement with the date of endodormancy release of 'Summit' on 28 November (332 DOY). The annual cycle of sucrose, which has a cryoprotective effect during winter, is well comprehensible and showed a close relationship to the annual course of minimum air temperature after leaf fall(r=-0.90). The nearly constant level of sucrose during ecodormancy (21.0 mg g-1 DW-1, 5 yr. mean) did not only allow deriving the date of endodormancy release but can also be helpful to define the beginning of ontogenetic development.},
  language  = {en}
}