Chilling-Dependent Release of Seed and Bud Dormancy in Peach Associates to Common Changes in Gene Expression

Reproductive meristems and embryos display dormancy mechanisms in specialized structures named respectively buds and seeds that arrest the growth of perennial plants until environmental conditions are optimal for survival. Dormancy shows common physiological features in buds and seeds. A genotype-specific period of chilling is usually required to release dormancy by molecular mechanisms that are still poorly understood. In order to find common transcriptional pathways associated to dormancy release, we analyzed the chilling-dependent expression in embryos of certain genes that were previously found related to dormancy in flower buds of peach. We propose the presence of short and long-term dormancy events affecting respectively the germination rate and seedling development by independent mechanisms. Short periods of chilling seem to improve germination in an abscisic acid-dependent manner, whereas the positive effect of longer cold treatments on physiological dwarfing coincides with the accumulation of phenylpropanoids in the seed

Kaolin, Ascophyllum nodosum

This is the peer reviewed version of the following article: Cabo, S., Aires, A., Carvalho, R., Vilela, A., Pascual-Seva, N., Silva, A.P. and Gonçalves, B. (2021), Kaolin, Ascophyllum nodosum and salicylic acid mitigate effects of summer stress improving hazelnut quality. J Sci Food Agric, 101: 459-475, which has been published in final form at https://doi.org/10.1002/jsfa.10655. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] BACKGROUND Various strategies are needed to mitigate the negative impact on or to increase fruit quality. The effect of spraying kaolin (K),Ascophyllum nodosum(An) and salicylic acid (SA), in trees with and without irrigation, on quality and sensorial attributes of hazelnut (Grada de Viseu cultivar) was investigated during two consecutive years (2016 and 2017) in a commercial orchard located in Moimenta da Beira, Portugal. RESULTS The treatments affected positively the biometric parameters nut and kernel weight, length, width, thickness and volume as well as the vitamin E level, antioxidant activity and content of some individual phenolics, such as protocatechuic acid, gallocatechin, catechin and epicatechin. The levels of amino acids in hazelnut kernels decreased in all the assayed treatments, while the kernel colour and sensorial attributes were not affected by the treatments. Hazelnut physical properties (nut and kernels), chemical and phytochemical composition and antioxidant activities were positively related. CONCLUSIONS The application of K, An and SA improved the hazelnut tree response to climate change, without compromising the hazelnut chemical and sensorial quality. Furthermore, due to the similar observations for the same treatments with and without irrigation, it can be stated that K, An and SA can be efficient and cost-effective tools to mitigate summer stress in rain-fed orchards.One of the authors (SC) acknowledges financial support by the Portuguese Foundation for Science and Technology (FCT) (PB/BD/113615/2015) under the Doctoral Programme 'Agricultural production chains - from fork to farm' (PD/00122/2012). The authors also acknowledge financial support provided by National Funds from FCT, under the projects UID/AGR/04033/2019 and UID/QUI/00616/2019. The authors acknowledge financial support of INTERACT project 'Integrative research in environment, agro-chains and technology', no. NORTE-01-0145-FEDER-000017, in its line of research entitled ISAC, co-financed by the European Regional Development Fund (ERDF) through NORTE 2020 (North Regional Operational Program 2014/2020). The authors are grateful to Francisco Oliva Teles for providing access to his orchard, Cristiana Teixeira, Iva Prgomet, Ivo Oliveira, Maria Cristina Morais, Silvia Afonso and Sofia Correia for their support in collecting nut samples in the orchard and to the Tasting Panel of ECVA-DeBA (UTAD) that participated in the sensory trials.Cabo, S.; Aires, A.; Carvalho, R.; Vilela, A.; Pascual-Seva, N.; Silva, AP.; Gonçalves, B. (2021). Kaolin,Ascophyllum nodosumand salicylic acid mitigate effects of summer stress improving hazelnut quality. Journal of the Science of Food and Agriculture. 101:459-475. https://doi.org/10.1002/jsfa.1065545947510