Crop and Pasture Science
Volume 65 Number 7 2014
Interdrought IV – Improving Crop Adaptation to Water-limited Environments
CP14019Improving water productivity in the Australian Grains industry—a nationally coordinated approach
Water availability is the primary limit to grain production in Australia, and as a consequence productivity growth in this sector slowed markedly during the recent Millennium drought. In 2008, the Australian grains industry established the 5-year, AU$17.6 million, Water Use Efficiency (WUE) Initiative, which challenged growers and researchers to lift WUE of grain-based production systems by 10%. The initiative demonstrated that water productivity could be improved by levels well above the 10% target, and there has been significant on-farm validation and adoption of innovations studied within the Initiative.
CP13331Optimum time of sowing for rainfed winter chickpea with one-pass mechanised row-sowing: an example for small-holder farms in north-west Bangladesh
Sowing time of chickpea (Cicer arietinum L.) in the High Barind Tract of north-west Bangladesh is critical to crop success. Soil water content and temperatures during crop establishment and subsequent crop growth will affect final yields. The preferred sowing time for chickpea in the region was determined to be 30 November to 10 December to reduce the risk of high temperatures and low water content in the soil profile during chickpea.This work may assist farmers to sow in a timely manner to avoid stresses that lower the final yield of chickpea.
Seasonal climate variability generates unforeseeable crop production risks in dryland farming. This study tackles the question of how to optimise crop design in such situations. Likely crop yield and production risk were predicted for combinations of genetic traits and crop management for a range of locations using crop simulation modelling. Significant yield advance at industry scale was found by targeting crop design to major geographic sub-regions. Traditional crop improvement does not currently capture fully the value of this specific adaptation.
Western Australian wheat growers face higher temperatures and lower rainfall in the future, which will challenge the profitability of wheat production on farm. This study looked at genetic (varieties) and management (row spacing and nitrogen) options to minimise the impact of climate change, using rain-out shelters to control rainfall; the results provided a platform to model wheat production in future climates. None of the strategies tested offset the expected fall in wheat production, but the study identified directions for wheat breeding (canopy vigour and root characteristics) and management to minimise yield losses in a hotter and drier climate.
The severity of water stress is projected to increase in many production environments and it has never been more important to deliver the findings of drought research to farmers. This paper focuses on one segment of the pathway—the process from genetic characterisation to cultivar delivery— with emphasis on wheat, one of the world’s most important food crops. A combination of targeted genetic diversity, improved phenotyping and enhanced exploitation of publicly available international germplasm is recommended as an efficient and effective strategy to improve crop productivity in water-limited environments.
CP14082Farmer participatory variety selection conducted in high- and low-toposequence multi-location trials for improving rainfed lowland rice in Lao PDR
Lowland rice in Lao PDR is predominantly grown under drought-prone, rainfed conditions in the wet season. In Laos farmers rely heavily on improved varieties to meet their household rice needs. As such we have introduced a farmer participatory variety selection (PVS) approach in multi-location trials (MLTs) conducted in both high and low toposequence positions and were able to identify lines adapted to less favourable conditions that were highly acceptable to farmers. Thus, incorporating the PVS-MLT approach has directly contributed to improved efficiency of the rice-breeding program.
CP13303Common beans, biodiversity, and multiple stresses: challenges of drought resistance in tropical soils
Research on improving drought tolerance in common bean (Phaseolus vulgaris) in Africa is reviewed. While tolerance to drought has been recovered, soil-related constraints limit expression of that tolerance. Multiple stress tolerance is required for wider impact in farmers’ fields.
CP13426Yield improvement and adaptation of wheat to water-limited environments in Australia—a case study
Farm management practices and new wheat varieties have increased wheat yields 4-fold in Australia over the last 120 years. Rates of gains have been impressive in both favourable and dry years but they are below the rate that is required to meet future global food demand. We discuss future opportunities to improve wheat yields in variable rainfed environments in the light of climate change.