Dr Xiaoxi Li1, Dr Jeremy Whish2, Mr Tony Swan1, Mr Mathew Dunn3, Dr Mehrshad Barary3, Dr John Kirkegaard1
1CSIRO Agriculture and Food, Canberra, Australia, 2CSIRO Agriculture and Food, St. Lucia, Australia, 3NSW Department of Primary Industries, Wagga Wagga, Australia
Biography:
Dr. Xiaoxi Li is a Research Scientist with CSIRO, Canberra, focusing on the GRDC funded Farming Systems project in NSW. His expertise lies in research data management, system analysis, and multi-criteria evaluation of diversified farming systems with legumes. Previously, he contributed to a new long-term trial at Rothamsted Research, UK. With a passion for plant-soil interaction, nutrient cycling, and environmental impact of agriculture, he has conducted research in China, Denmark, the UK, and Australia.
Abstract:
Improving system efficiency is imperative for sustainable and profitable crop production for Australian dryland farming. Modelling reveals inefficiencies in systems involving fallow or continuous wheat with low nitrogen strategies, emphasising the importance of optimised crop sequences. Furthermore, the relatively low nitrogen usage in the Australian grains industry underscores the necessity for strategic nitrogen management to realise yield potential. To address these challenges, four six-year field experiments were initiated in 2017 across Wagga Wagga, Greenethorpe, Urana, and Condobolin in Southern NSW. Key treatments include diversified crop sequences with legumes, cereal intensity, early versus timely sowing, and low versus high nitrogen strategies. While all phases of each crop sequence are present annually, the specific crop sequences vary across site. Mean annual N fertiliser input was 57 and 111 kg N ha-1 for the low and high N strategy, respectively. Notably, in the low nitrogen strategy, fertiliser use decreased from 79 to 43 kg N ha-1 yr-1 in systems with a legume compared to those without, highlighting the use of legumes to substitute partly external N fertiliser. Once the grain N concentration data is complete, the use efficiency of available N (including N fertiliser plus pre-sowing soil mineral N) at both crop and system levels will be analysed and presented. This research offers insights into alternative cropping systems to enhance productivity, profitability, and sustainability through strategic agronomic management measures.