Although Australia’s mean surface air temperatures, daytime maximum temperatures and overnight minimum temperatures have warmed, there has, somewhat paradoxically, been an increase in frost risk across much of southern Australia. Recent regional and localised changes in the frequency, timing and duration of minimum temperature extremes all show increasing risk. Over the last six decades, more frost events and longer frost season length have contributed to an increase in the potential for frost-related crop losses. This paper examines and quantifies the extent of the production risk changes for 65 sites across the Australian wheatbelt and shows how managing frost risk has become more challenging over the last two decades and will potentially remain so in the near future.

Cold temperature stress at the reproductive stage can cause significant yield reductions in rice. Floral characteristics were examined in relation to spikelet sterility to determine tolerance mechanisms at flowering, with enhanced anther dehiscence identified as important. Identification of traits and QTLs associated with cold tolerance will provide useful tools to breeders to maximize efficiency of rice improvement and yield stability for cold temperature environments.

Foxtail millet, an arid crop, is ideal for the changing climate. Drought tolerance of this crop depended more on transpiration efficiency (TE) and harvest index (HI) than on total water use (T). Germplasm races offered specific choices for T, TE or HI selection.

Weeds are a major cost to canola production in Australia but herbicide control options are running out as resistance spreads. Crop competition using vigorous hybrid canola cultivars combined with crop densities of at least 40 plants/m² is essential to avoid high levels of weed seed production and spread, and crop yield loss. Crop competition for weed control is another important tool for reducing weed impacts.

Scarce and expensive irrigation water needs to be used effectively. After the onset of root expansion, forage turnip yield increased in proportion to the amount of irrigation applied when the soil remained below field capacity. However, scarce irrigation should be applied between the onset of root expansion and approximately 8 weeks later, when the response to irrigation ( kg DM ha^–1 mm^–1) was greatest.

Understanding how reducing nitrogen (N) fertiliser application may affect origin of plant N in soybean is important to maximize fertilizer use efficiency. Using dual-labelling (¹⁵N and ¹³C) technique, the proportion of N origins in plant and C assimilation were quantified under two N levels. Greater photosynthetic C allocation to roots would greatly contribute to the alteration of N acquisition pattern when fertiliser N supply is reduced.

This experiment quantified the effects of the depth and salt concentration of the watertable on the growth dynamics and biomass accumulation of Rhodes grass. The presence of non-saline watertable at a depth of 25 cm produced a 5-fold greater biomass, quintupled the water consumption and presented groundwater use efficiency 30% higher and leaf blades 50% longer compared with deeper watertables.

Quantification of forage quality is essential for the identification of elite genotypes in forage grass breeding. However, current methods are labour-intensive, low-throughput and cost-prohibitive for commercial breeding programs. An accurate high-throughput micro-plate-based protocol has been developed and validated, with the ability to simultaneously process and quantify WSC and plant protein with a high level of automation, and an increase in sample processing of ~10-fold compared with commonly-used methods, along with a 3-fold cost reduction.

The genetic potential of white clover germplasm, from broad geographic origins, was evaluated based on their F₁ crosses to three elite New Zealand cultivars. The parents and progeny were evaluated at Palmerston North under rotational grazing by sheep. Three morphological traits and seasonal dry matter yield were measured over four years. The study indicated that choice of adapted cultivar with which to cross is important, and germplasm from Australasia was a valuable source of adaptive variation.