Impact of fruit orientation and pelleting material on water uptake and germination performance in artificial substrate for sugar beet.

Water uptake into seeds is a fundamental prerequisite of germination and commonly influenced by commercial seed enhancement technologies. The effect of fruit orientation and contrasting pelleting materials on germination and biological performance of sugar beet was assessed. The results indicated there was orientation dependent fruit shrinkage of 37% for the operculum side supplied by moisture compared to 4% for the basal pore side. The expansion rate of 5% compared to the original size, which was also observed for non-shrinking seeds, indicated this was a temporary effect. This behaviour has importance for the application pelleting materials to seeds. Pellets composed of materials exhibiting low levels of swelling act as a water distribution layer which increased germination rates. Careful selection of pelleting material is crucial as it has direct implications on germination speed and subsequent establishment rates.

Tracking wireworm burrowing behaviour in soil over time using 3D X-ray computed tomography.

BACKGROUND: Wireworms (larvae of the click beetle, Elateridae) are a significant agricultural pest, causing crop damage and reducing yields globally. Owing to the complex nature and opacity of the soil environment, research to investigate wireworm behaviour in situ has been scarce. X-ray computed tomography (CT) has previously been demonstrated as a powerful tool to independently visualise the 3D root system architecture, macroinvertebrate movement and distribution of burrow systems in soil, but not simultaneously within the same sample. In this study, we apply X-ray CT to visualise and quantify wireworms, their burrow systems and the root architecture of two contrasting crop species (Hordeum vulgare and Zea mays) in a soil pot experiment scanned at different time intervals. RESULTS: The majority of wireworm burrows were produced within the first 20 h post inoculation, suggesting that burrow systems are established quickly and persist at a similar volume. There was a significant difference in the volume of burrow systems produced by wireworms between the two crop species suggesting differences in wireworm behaviour elicited by crop species. There was no significant correlation between burrow volume and either root volume or surface area, indicating this behavioural difference is caused by factor(s) other than the mass of root systems. CONCLUSION: X-ray CT shows potential as a non-destructive technique to quantify the interaction of wireworms in the natural soil environment with crop roots, and aid the development of effective pest management strategies to minimise their negative impact on crop production. © 2020 Society of Chemical Industry.

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

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.

Interfacial kinetics in a model emulsion polymerisation system using microelectrochemical measurements at expanding droplets (MEMED) and time lapse microscopy.

Physicochemical processes that take place at the oil-water interface of an epoxy-amine emulsion polymerisation system influence the properties and structural morphology of the polymeric microparticles formed. Investigating these processes, such as the transport of monomers across the liquid/liquid interface brings new understanding which can be used to tune polymeric morphology. Two different approaches are used to provide new insights on these processes. Microelectrochemical measurements at expanding droplets (MEMED) is used to measure the transfer of amine from an organic phase comprised of epoxide and amine into an aqueous receptor phase. The rate of amine transfer across the liquid/liquid interface is characterised using MEMED and finite element method modelling and kinetic values are reported. Time lapse microscopy of epoxide droplets held in deionised water or an aqueous amine solution heated to different temperatures is further used to characterise epoxide dissolution into the aqueous phase. Mass-transport of epoxide into the aqueous phase is shown to be temperature-dependent. Epoxide homopolymerisation at the droplet-water interface is found to influence the rate of epoxide droplet dissolution. The rate of the epoxy-amine cure reaction is shown to be faster than the rate of the epoxide homopolymerisation reaction. The combination of methods used here is not limited to emulsion polymerisation and should find application in a myriad of processes at liquid/liquid interfaces.

End-diastolic and end-systolic volume from the left ventricular angiogram: how accurate is visual frame selection? Comparison between visual and semi-automated comnputer-assisted analysis.

BACKGROUND: End-diastolic (ED), end-systolic (ES) left ventricular (LV) volumes and LV ejection fraction (LVEF) are important parameters for clinical decision making in heart disease. In clinical practice the frames from cine-angiography with the largest and smallest opacified LV areas are visually selected and the endocardial borders traced as LVED and LVES contours, respectively. We compared the accuracy of this visual method using two frames with a semi-automated computer assisted frame-by-frame analysis of the complete opacified cardiac cycles. METHODS AND RESULTS: In 17 patients a biplane LV cine-angiogram was obtained at 25 frames/s. Complete frame-by-frame analysis was performed using semi-automatic border detection software. Experienced independent observers visually selected and manually traced LVED and LVES in the so-called visually assessed two-frame method in a consensus meeting. LV volumes were calculated by the area-length method. Mean LVEDV, LVESV and LVEF were 133 +/- 57, 56 +/- 40 ml and 61 +/- 16%, respectively, for the visually assessed two-frame method, and 117 +/- 49, 53 +/- 33 ml and 60 +/- 13%, respectively, for the semi-automated computer assisted frame-by-frame method. LVEDV was significantly higher in the visually assessed two-frame method (p < 0.01). Linear regression analysis showed an excellent correlation between semi-automated computer-assisted frame-by-frame and the visually assessed two-frame LVEDV (y = 1.2x - 2.9; r2 = 0.98), LVESV (y = 1.2x - 8.2; r2 = 0.97) and good linear correlation for LVEF (p = 1.2x - 3.6; r2 = 0.82). Bland-Altman analysis showed respectively a bias of 16.4, 2.4 ml and 5.0% with overall wide limits of agreement (-6.6 and 39.4 ml; -16.6 and 21.4 ml; -9.0% and 19.1%). CONCLUSION: Correlation is excellent when visually assessed LVED and LVES are compared with a semi-automated computer assisted frame-by-frame analysis. However, the visually assessed two-frame method tends to overestimate the volumes obtained by semi-automated computer-assisted frame-by-frame analysis, especially for LVEDV, indicating that visual selection will yield a higher LVEF, which may influence clinical decision making.