Functional Plant Biology Functional Plant Biology Society
Plant function and evolutionary biology
RESEARCH ARTICLE

Improving nitrogen use efficiency in plants: effective phenotyping in conjunction with agronomic and genetic approaches

Giao N. Nguyen A and Surya Kant A B
+ Author Affiliations
- Author Affiliations

A Agriculture Victoria, Grains Innovation Park, 110 Natimuk Road, Horsham, Vic. 3400, Australia.

B Corresponding author. Email: surya.kant@ecodev.vic.gov.au

Functional Plant Biology - https://doi.org/10.1071/FP17266
Submitted: 26 September 2017  Accepted: 4 January 2018   Published online: 8 February 2018

Abstract

For global sustainable food production and environmental benefits, there is an urgent need to improve N use efficiency (NUE) in crop plants. Excessive and inefficient use of N fertiliser results in increased crop production costs and environmental pollution. Therefore, cost-effective strategies such as proper management of the timing and quantity of N fertiliser application, and breeding for better varieties are needed to improve NUE in crops. However, for these efforts to be feasible, high-throughput and reliable phenotyping techniques would be very useful for monitoring N status in planta, as well as to facilitate faster decisions during breeding and selection processes. This review provides an insight into contemporary approaches to phenotyping NUE-related traits and associated challenges. We discuss recent and advanced, sensor- and image-based phenotyping techniques that use a variety of equipment, tools and platforms. The review also elaborates on how high-throughput phenotyping will accelerate efforts for screening large populations of diverse genotypes in controlled environment and field conditions to identify novel genotypes with improved NUE.

Additional keywords: biosensors, chlorophyll pigments, N metabolism, plant phenomics.


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