Effects of Cryoprotectants and Post-storage Priming on Seed Germination of Sugi (Cryptomeria japonica

Abstract

Among the ex situ methods for the preservation of forest tree germplasm, conventional seed banking is considered the most efficient method for the majority of species whilst cryopreservation has an important role in long-term conservation. The influence of cryoprotectants prior to liquid nitrogen (LN) storage and osmoconditioning priming treatments with polyethylene glycol (PEG) after LN storage were evaluated for germination (%), germination value (GV) and mean germination time (MGT) in seeds of Cryptomeria japonica. Sugi seeds were treated with two cryoprotectants (DMSO and PVS2) before immersion into LN and stored for three days. Although the C. japonica seeds survived liquid nitrogen treatment, their viability was reduced from 25 % of intact seeds to 17 % in LN. The seeds treated with 35 % DMSO showed higher germination (28 %) as compared with seeds directly-immersed in LN without cryoprotectant treatment. In contrast, PVS2 pretreated seeds decreased germination (13 %). Two concentrations of PEG priming treatments were carried out. Osmoconditioning treatment in -0.4 MPa PEG solution after removal from LN enhanced the subsequent germination percentage and decreased MGT. PEG treatments at both -0.4 and -1.2MPa to PVS2 pretreated seeds before cryopreservation partially alleviated the negative effect of PVS2. DMSO pretreated seeds immersed into LN and treated with -0.4MPa PEG maintained the 28 % of germination obtained in the control conditions and reduced the mean germination time (MGT). It can therefore be summarized that pretreatment with 35 % DMSO was suitable for the cryopreservation of C. japonica seeds whilst the PEG priming treatment circumvented imbibitional damage after LN exposure.

Influence of Pre-sowing Seed Treatments on Germination Properties and Early Seedling Growth of Acacia cyanophylla.

“…These include hydropriming, halopriming, hardening and osmopriming [17], hormone priming, solid matrix, humidification and stratification and thermal shock [25]- [32].The first four approaches are the most common for the purposes of priming [12]. It has been reported that seed priming results in the enhancement of seed germination of plants such as mungbean (Vigna radiata) [33], common alder (Anlus glutinosa) [4] and several acacia species [29]- [35]- [36]- [9], (Ziziphus spinachristi) [45], okra (Abelmoschus esculentus) [5],enhancement of emergence rate of armada pine (Pinus armadii) [46], Japanese cedar (Cryptomeria japonica) [26], Norway spruce (Picea abies), silver birch (Betula pendula), beech (Fagus sylvatica) and shore pine (Pinus contorta) [40], common alder (Alnus glutinosa) and downy brich (Betula pubescens) [4] maize (Zea mays) and chickpea (Cicer arietinum) [19]- [20], mungbean [33], wheat (Triticum aestivum) [27], cowpea (Vigna unguiculata) [41], increased uniformity and seedling establishment of red oak (Quercus rubra) [44], marica (Mimosa bimucronata) [8], lodgepole pine (Pinus contorta) and white spruce (Picea glauca) [22], and increased output of barley (Hordeum vulgare) [34], maize and chickpea [19]- [21] mungbean [33], and seedlings quality of christimas tress (Pinus brutia) [24], Acacia nilotica [30]. This research is designed to evaluate the response of A. cyanophylla seeds to pre-sowing seed treatments.…”