Seed priming enhances early growth and improves area of soil exploration by roots

Introduction: Seed priming has been conducted for centuries with growth advantages reported for a variety of different crops. Previous work has suggested priming does not offer a yield advantage despite an increased early growth if grown under ideal conditions. However, how these advantages unfold in regards to early root development is largely unknown.Results: We observed accelerated germination speed in primed seeds regardless of applied seed enhancement technology i.e. coating or pelleting. Additionally, we found significant differences in lateral root development in primed seeds vs non-primed seeds. Furthermore, we recorded an increase in volume and surface of embryo and perisperm indicating a distinct morphological change during the germination process of primed seeds compared to non-primed seeds.Conclusions: We attribute the enhanced early plant development in primed seeds to increased root development and thus enhanced volume of the soil resource mined for nutrients. This improvement can be detected four days after emergence within the root system throughout the early plant development despite an early transition from seed reserves to soil based growth. The understanding of below ground root architecture characteristics can improve the selection of appropriate seed enhancement technologies and seedbed management practices

Soil seedbed engineering and its impact on germination and establishment in sugar beet (Beta vulgaris L.) as affected by seed-soil contact

Seed-soil contact plays an essential role in the process of germination as seeds absorb water through direct contact with the moist soil aggregates that surround them. Factors influencing seed-soil contact can be considered as those pertaining to soil physical properties (e.g. texture, bulk density, porosity, etc.) and those related to environmental conditions (e.g. temperature, rainfall, frost). Seed-soil contact is furthermore influenced by the specific field management processes that farmers apply, which have developed significantly over the last 30 years. However, the precise effect of cultivation on the actual contact area of the seed with the surrounding soil is based on a series of assumptions and still largely unknown. This review considers the influence of soil management and its direct impact on seed-soil contact and establishment. We review the state of the art in methodology for measuring seed-soil contact and assess the potential for soil amendments such as plant residues and waste materials to improve seed-soil contact. Engineering the ‘optimal’ seed-soil contact remains a challenge due to the localized variation between the interaction with field management techniques and soil texture, climatic conditions and crop type. The latest imaging approaches show great promise to assess the impact of management on germination. Combining the techniques with the latest network models offer great potential to improve our ability to accurately predict germination, emergence and establishment

Quantification of differences in germination behaviour of pelleted and coated sugar beet seeds using X-ray Computed Tomography (X-ray CT)

Seed enhancement technologies i.e. priming, pelleting and coating have been extensively9 used throughout the last century to improve crop yield and to reduce losses associated with pest infestation. However, until recently, it has not been possible to non-destructively assess the effect of seed enhancement technologies belowground due to the opacity of soil. Using X- ray Computed Tomography (X-ray CT) we undertook a 4D visualisation of the germination process of four different sugar beet seed enhancement treatments (untreated / naked, coated, pelleted and pelleted + coated) in soil. The aim of this study was to improve the understanding of the germination process in the natural environment of the seed to inform future soil management and seed enhancement processes. Using X-ray CT we were able to quantify the germination and establishment process of different seed enhancement technologies in soil non-destructively for the first time. We observed a delay in seedling growth posed by the addition of a physical barrier, i.e. the seed coating. However, an enhanced radicle growth rate was observed in pelleted, as well as pelleted and coated seeds, after overcoming the physical barrier. The disadvantage posed by the addition of seed coating was overcome after four days of seedling growth. Further work should focus on refinements to the type and composition of the pelleting which we observed to have a retarded effect on seed germination

Quantification of seed-soil contact of sugar beet (Beta vulgaris) using X-ray Computed Tomography

© 2017 The Author(s). Background: Seed-soil contact is important to ensure successful germination, however, there is a paucity of reported studies that have quantified the microstructure at and around this critical interface, mainly due to the opacity of soil. Results: Here we describe a novel methodology to non-destructively calculate the seed-soil contact area using X-ray Computed Tomography. Under controlled conditions, we observed that seed-soil contact was strongly influenced by the size and type of seed, with a seed-soil contact of ca. 15% for naked sugar beet seeds compared to ca. 32% for pelleted and coated seeds. Similar results were obtained for seeds sampled from the field albeit with a higher spatial variability. Conclusions: By application of this new quantification method it is hoped seed enhancement technologies can be optimised and ultimately seedbed preparation improved to ensure better germination

Improving In Vitro Generated Cartilage-Carrier-Constructs by Optimizing Growth Factor Combination

The presented study is focused on the generation of osteochondral implants for cartilage repair, which consist of bone substitutes covered with in vitro engineered cartilage. Re-differentiation of expanded porcine cells was performed in alginate gel followed by cartilage formation in high-density cell cultures. In this work, different combinations of growth factors for the stimulation of re-differentiation and cartilage formation have been tested to improve the quality of osteochondral implants. It has been demonstrated that supplementation of the medium with growth factors has significant effects on the properties of the matrix. The addition of the growth factors IGF-I (100 ng/mL) and TGF-β1 (10 ng/mL) during the alginate culture and the absence of any growth factors during the high-density cell culture led to significantly higher GAG to DNA ratios and Young’s Moduli of the constructs compared to other combinations. The histological sections showed homogenous tissue and intensive staining for collagen type II

Extrinsic Fluorescent Dyes as Tools for Protein Characterization

Noncovalent, extrinsic fluorescent dyes are applied in various fields of protein analysis, e.g. to characterize folding intermediates, measure surface hydrophobicity, and detect aggregation or fibrillation. The main underlying mechanisms, which explain the fluorescence properties of many extrinsic dyes, are solvent relaxation processes and (twisted) intramolecular charge transfer reactions, which are affected by the environment and by interactions of the dyes with proteins. In recent time, the use of extrinsic fluorescent dyes such as ANS, Bis-ANS, Nile Red, Thioflavin T and others has increased, because of their versatility, sensitivity and suitability for high-throughput screening. The intention of this review is to give an overview of available extrinsic dyes, explain their spectral properties, and show illustrative examples of their various applications in protein characterization

Tissue engineering of functional articular cartilage: the current status

Osteoarthritis is a degenerative joint disease characterized by pain and disability. It involves all ages and 70% of people aged >65 have some degree of osteoarthritis. Natural cartilage repair is limited because chondrocyte density and metabolism are low and cartilage has no blood supply. The results of joint-preserving treatment protocols such as debridement, mosaicplasty, perichondrium transplantation and autologous chondrocyte implantation vary largely and the average long-term result is unsatisfactory. One reason for limited clinical success is that most treatments require new cartilage to be formed at the site of a defect. However, the mechanical conditions at such sites are unfavorable for repair of the original damaged cartilage. Therefore, it is unlikely that healthy cartilage would form at these locations. The most promising method to circumvent this problem is to engineer mechanically stable cartilage ex vivo and to implant that into the damaged tissue area. This review outlines the issues related to the composition and functionality of tissue-engineered cartilage. In particular, the focus will be on the parameters cell source, signaling molecules, scaffolds and mechanical stimulation. In addition, the current status of tissue engineering of cartilage will be discussed, with the focus on extracellular matrix content, structure and its functionality