Effects of Fluridone Treatment on Seed Germination and Dormancy-associated Gene Expression in an Ornamental Peach (<i>Prunus persica</i> (L.) Batsch)

Abstract

Fluridone, an inhibitor of carotenoid biosynthesis, is known to prevent abscisic acid (ABA) biosynthesis and to affect the germination and dormancy of seeds in several plant species. This study investigated the effects of fluridone on seed germination of the ornamental peach 'Yaguchi', and on the transcript levels of genes related to seed dormancy in this plant. Seeds were rinsed for 2 days under running tap water (RS), then soaked for 1 day in 100 μM fluridone (F), and kept at 5°C for 2 weeks (2W). The germination rate significantly increased from 0% to 9.5% in the RS+F treatment and to 71.4% in the RS+F+2W treatment, while no germination occurred in the RS and RS+2W treatments. Seedlings in RS+F and RS+F+2W treatments formed dwarf shoots, i.e. about 10 cm, and morphological lesions on the leaves. The ABA content in embryonic axes decreased after RS and increased with RS+2W. It was decreased by the RS+F+2W treatment. RS+F+2W downregulated ABA-hy3, which encodes enzymes with key roles in ABA catabolism, while its effects on 9-cisepoxycarotenoid dioxygenase (NCED1) in relation to ABA synthesis fluctuated. In contrast, Empfindlicherim Dunkelroten Licht 1 (EID1) was upregulated after fluridone treatment, suggesting that fluridone may activate positive ABA signaling pathways. Expression of GA2-oxidase8 (GA2-ox8) was not affected by fluridone. D-34) were downregulated in the RS+F+2W treatment, suggesting that the expression of these genes are controlled by low temperature and the ABA inhibitor, and are involved in seed dormancy. These results suggest that ABA inhibitor treatments can be an alternative method to promote germination by controlling ABA content and its metabolism, and consequently changing expression of certain ABA-and dormancy-related genes including ABA-hy3, EID1, LeMADS, and LEA D-34, even under insufficient chilling conditions. MADS-box protein JOINTLESS (LeMADS) and Late embryogenesis abundant protein D-34 (LEA

Study of Germination Efficiency and Temperature/Drowning Resistance in some Ornamental Plants treated with Ultra High Dilute Compounds

“…Comparing the variations of these two and the variations in total free carbohydrate content (Figure 3b), it can be concluded that treatment of UHDs leads to stimulation and acceleration of growth, and the main focus is not on differentiation. The increments in ABA content which is the correspondence for further stimulates and accelerates rooting [30,31] in S. officinalis, and its decrements in the other two samples is a sign of awakening and complete withdrawal of seed metabolism from dormancy. The levels of SA have also increased in S. officinalis treated using UHDs.…”

Methods for Improving the Germination of Rhodotypos scandens (Thunb.) Makino Seeds through Endocarp Removal

“…scandens seeds when used in conjunction with ER ( Figure 3 ). In previous studies, fluridone has been shown to induce seed germination in Prunus persica , Caragana stipitate, and Nicotiana plumbaginifolia [ 50 , 51 , 52 ]. Additionally, it is worth noting that fluridone induced an augmentation in annual Orobanche minor germination without diminishing endogenous ABA levels [ 53 ].…”

Transcriptomics Analysis Reveals a Putative Role for Hormone Signaling and MADS-Box Genes in Mature Chestnut Shoots Rooting Recalcitrance

“…In peach and apple, DAM MADS-box genes, closely related to SVP, integrate phytohormone and environmental signals to control bud dormancy, and a possible link with the Squamosa gene MdSPL9 has been proposed in apple [50,51]. Moreover, ABA-controlled expression of a Jointless gene and an SVP gene in peach and aspen, respectively, has been described [45,52], and ABA content in pear was found to be greater in mature tissues [53]. Therefore, activity of these TFs might be impeding the necessary reprogramming of cells in the mature shoots.…”