Original Research ARTICLE
Day-length is involved in flooding tolerance response in wild type and variant genotypes of rootstock Prunus cerasifera L.
- 1Department of Agricultural, Food and Agri-environmental Sciences, University of Pisa, Italy
- 2Faculty of Agricultural and Food Sciences, University of Milan, Italy
- 3Department of Agricultural and Forestry Science, University of Tuscia, Italy
- 4Università degli Studi della Tuscia, Italy
Scenarios for current and predicted climate changes require crops with an improved adaptability to mutable environmental features. A condition of hypoxia in the roots activates coping mechanisms to develop strategies to overcome the reduction of oxygen. Prunus spp are hypoxia-sensitive woody species and although much information has been accumulated in the last decades, many physiological mechanisms are still unclear. To verify whether anoxic plant responses are also regulated by photoperiod, plants of Mr.S.2/5-WT plum, and its variant genotypes S.4 tolerant (plus) and S.1 sensitive (minus) to flooding, were grown in greenhouse and were submitted from mid-July to natural (NP) and to constant photoperiod (CP) until the first ten-days of October. From mid-September plants from each genotype, grown under the two photoperiods, were divided into two groups applying long-term flooding only to one of them. Gas exchange parameters, energetic and biochemical activities, leaf chlorophyll contents, and stress symptoms were measured at different times, whereas soluble sugars were quantified in leaves and roots 14 days after flooding, when stress symptoms in WT and S.1 became prominent. Seasonal changes in photoperiod played a role in the adaptability to anoxia, although flooding stress response differed among the three genotypes. Anoxia affected leaf gas exchange and S.4 flooded-leaves retained higher ACO2 under conditions of NP and CP. Leaf soluble sugar concentration differed among genotypes. Irrespective of photoperiod, S.4 anoxic-leaf sugar concentration was the lowest, except for sorbitol. S.4 anoxic-roots under CP accumulated the highest levels of sucrose and sorbitol. An influence by the photoperiod was observed in WT and S.1 anoxic-leaves, whereas, irrespective of photoperiod, S.1 anoxic roots accumulated the lowest concentration of sugars. Leaf and root respiratory activity in flooded-plants was highest in S4, and ADH activity increased in all flooded plants under CP, but a higher activity was observed only in S.1 under NP during flooding. Results are consistent with the hypothesis that the S.4 genotype has a plastic adaptability to flooding stress, escaping from the photoperiod regulatory cross-talk system, and can better cope with the new scenarios generated by climate changes.
Keywords: Anoxia,, Off-Season Flooding, photoperiod, physiological plasticity, Plum, seasonal changes
Received: 03 Jan 2019;
Accepted: 10 Apr 2019.
Edited by:Guangcheng Shao, Hohai University, China
Reviewed by:Petronia Carillo, Università degli Studi della Campania Luigi Vanvitelli Caserta, Italy
Keisuke Nagai, Nagoya University, Japan
Copyright: © 2019 Iacona, PISTELLI, Cirilli, Gatti, Mmancinelli, Ripa and Muleo. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Rosario Muleo, Università degli Studi della Tuscia, Viterbo, Italy, firstname.lastname@example.org