Samuel Joalland

Samuel Joalland

orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 November 2011 in Geoderma
Verified
Journal Article
Closed access
BMBudiman Minasny
Budiman Minasny
AMAlex McBratney
Alex McBratney
VBVeronique Bellon-Maurel
Veronique Bellon-Maurel
JRjean-michel roger
jean-michel roger
AGAlexia Gobrecht
Alexia Gobrecht
SJSamuel Joalland
Samuel Joalland

19 May 2018 in Remote Sensing
Verified
Journal Article
Open access
PDF file
SJSamuel Joalland
Samuel Joalland
CSClaudio Screpanti
Claudio Screpanti
HVHubert Vincent Varella
Hubert Vincent Varella
MRMarie Reuther
Marie Reuther
MSMareike Schwind
Mareike Schwind
Frank LiebischFrank Liebisch
Frank Liebisch
The rapid development of image-based phenotyping methods based on ground-operating devices or unmanned aerial vehicles (UAV) has increased our ability to evaluate traits of interest for crop breeding in the field. A field site infested with beet cyst nematode (BCN) and planted with four nematode susceptible cultivars and five tolerant cultivars was investigated at different times during the growing season. We compared the ability of spectral, hyperspectral, canopy height- and temperature information derived from handheld and UAV-borne sensors to discriminate susceptible and tolerant cultivars and to predict the final sugar beet yield. Spectral indices (SIs) related to chlorophyll, nitrogen or water allowed differentiating nematode susceptible and tolerant cultivars (cultivar type) from the same genetic background (breeder). Discrimination between the cultivar types was easier at advanced stages when the nematode pressure was stronger and the plants and canopies further developed. The canopy height (CH) allowed differentiating cultivar type as well but was much more efficient from the UAV compared to manual field assessment. Canopy temperatures also allowed ranking cultivars according to their nematode tolerance level. Combinations of SIs in multivariate analysis and decision trees improved differentiation of cultivar type and classification of genetic background. Thereby, SIs and canopy temperature proved to be suitable proxies for sugar yield prediction. The spectral information derived from handheld and the UAV-borne sensor did not match perfectly, but both analysis procedures allowed for discrimination between susceptible and tolerant cultivars. This was possible due to successful detection of traits related to BCN tolerance like chlorophyll, nitrogen and water content, which were reduced in cultivars with a low tolerance to BCN. The high correlation between SIs and final sugar beet yield makes the UAV hyperspectral imaging approach very suitable to improve farming practice via maps of yield potential or diseases. Moreover, the study shows the high potential of multi- sensor and parameter combinations for plant phenotyping purposes, in particular for data from UAV-borne sensors that allow for standardized and automated high-throughput data extraction procedures.

9 September 2015 in Plant and Soil
Verified
Journal Article
Closed access
PDF file
SJSamuel Joalland
Samuel Joalland
CSClaudio Screpanti
Claudio Screpanti
AGAlain Gaume
Alain Gaume
AWAchim Walter
Achim Walter