A comparison of field assessment methods for lucerne inoculation experiments

Abstract

Effective and practical measurement methods for assessing field inoculation experiments are needed to identify inoculants that could improve lucerne establishment. In this study, assessment potential of different existing measurement methods (plant height, Dualex 4 Scientific leaf-clip meter, GreenSeeker handheld crop sensor, drone-acquired orthomosaic calculation, yield, nutrient analysis and nodule assessment) were compared across 12 inoculation treatments applied to lucerne (Medicago sativa L.) at 3 sites. F-values were used to compare the potential of different methods to separate inoculation treatments. The handheld GreenSeeker measuring normalised difference vegetation index (NDVI) showed the greatest potential for separating inoculation treatments in fields where lucerne had not previously been cultivated, followed by visible atmospherically resistant index (VARI) and green-red vegetation index (GRVI) from drone-acquired orthomosaics. These methods are non-destructive, low cost, require low labour input, fast, and do not require sample preparation, and thus are efficient measurement methods for disaggregating treatments in field inoculation experiments.

Description

Acknowledgements: We thank the field station staff for their efforts in managing the field experiments and collecting data, and Dr. Ahmed Mukhtar for his assistance in data collection. Lin Tang acknowledges the postdoctoral scholarship supported by Carl Tryggers Stiftelse (CTS 19:275). © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Version of Scholarly Record of this Article is published in Acta Agriculturae Scandinavica, Section B — Soil & Plant Science, 2022, available online at: http://www.tandfonline.com/10.1080/09064710.2022.2111340 . Keywords: Forage; lucerne; nodulation; nutrient content; spectral reflectance; yield; Europe; Sweden; loamy sand; temperate oceanic climate; humid continental climate.

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Citation

Lin Tang, Julien Morel, Magnus Halling, Linda Öhlund & David Parsons (2022) A comparison of field assessment methods for lucerne inoculation experiments, Acta Agriculturae Scandinavica, Section B — Soil & Plant Science, 72:1, 860-872, DOI: 10.1080/09064710.2022.2111340

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