Quality and germination capacity of seed material harvested from an Arrhenatherion meadow

Abstract

Arrhenatherion meadows are an endangered type of semi‐natural grassland in Europe, and their conservation and restoration is an important policy objective. Recent research has led to development of techniques for harvesting seed material from regional donor sites and strategies for re‐establishment of species‐rich grassland, but their practical application requires that consumers are guaranteed sufficient seed quality of directly harvested material. Methods for the evaluation of purity, thousand seed weight (TSW) and germination capacity were developed and tested, a pre‐condition to define the optimal seeding rate for this vegetation type (2000–3000 seeds m−2). The assessment was based on seed obtained by two harvesting techniques: on‐site threshing (OST) and seed stripping (SS). Materials from both methods obtained 63% pure seeds. The TSW differed significantly between harvesting methods: the OST provided greater seed weight (1·057 g) than the SS (0·84 g). Two trials were implemented to define criteria for the germination capacity test. Organic growing media obtained the best and most homogenous results in a first comparative germination test. In the second trial, different dormancy‐breaking treatments were compared, each with and without pre‐chilling, namely: addition of potassium nitrate (KNO3), addition of gibberellic acid (GA3) and without addition of chemicals (WA). The germination capacity of the treated variants KNO3, GA3 and pre‐chilling was lower than that for WA. The harvesting method significantly influenced quality and quantity of the seed material, whereas the substrate and dormancy‐breaking treatments had no effect.

Influence of different storage conditions on quality characteristics of seed material from semi‐natural grassland

“…The experimental design for the greenhouse test was defined following the results of pre‐tests in a phytotron (Haslgrübler et al ., ). The material was stored over 3 years (2009–2012) under different storage conditions: (i) room temperature, 18–23°C (room), (ii) cooling chamber, 2–5°C with 40–50% humidity (cool) and (iii) freezer, −18°C (freeze).…”

“…The separated seeds were counted and weighed for both harvesting methods. Afterwards, the subsamples of 1·25 g were mixed again and surface‐sown in bulb trays (40 cm × 60 cm × 6 cm) on organic growing media (OGM), which performed best in the pre‐tests (Haslgrübler et al ., ). In total, twenty‐four trays (two harvesting methods × three storage variants × four replicates) were placed in the greenhouse and watered at least once a day to keep the OGM on a constant level of soil moisture.…”

Floristic diversity of extensively used fresh meadows (6510) in the Wielki Łęg Obrzański complex

“…At present in Europe effective methods are searched for to restore the nature value of species-rich meadow communities, e.g. from the Arrhenatherion alliance [13,[34][35][36]. One of the proposed solutions is to collect seeds or hay from donor localities, such as phytocenoses developed in the typical form with a considerable richness of species characteristic of the recreated plant community [37][38][39].…”

“…In the last 25 years, in some European regions we have been observing a gradual disappearance of plant communities from the Arrhenatherion alliance, formerly developed in their typical form [11,12]. For this reason, restoring species-rich fresh meadows is at present a priority for conservation groups in central Europe [13,14]. The present, frequently depleted structure of Arrhenathereterum elatioris phytocenoses and the plant community Poa pratensis-Festuca rubra have been influenced first of all by the changes in their use, both its reduced management and its intensification, as well as changes in habitats; this also applies to other types of communities within the class Molinio-Arrhenatheretea [15,16].…”

Native seed trade of herbaceous species for restoration: a European policy perspective with global implications

“…However, much of the native seed market in Europe regarding herbaceous species is unregulated and poor seed quality is a common occurrence (Laverack et al ; Ryan et al ; Haslgrübler et al ; Marin et al ). In the United Kingdom, the native seed market is estimated to grow to 120–140 tons and be worth £9–17 million by 2019/2020 (UK Native Seed Hub ).…”