This review explores how speed breeding protocols that hasten plant growth and development could be applied to shorten breeding cycles and accelerate research activities in orphan crops. Authors' contribution: LTH and WP conceived and outlined the review; TC and WP contributed technical knowledge of breeding orphan crops; SK contributed concepts and technical knowledge for converting shipping containers into speed breeding capsules; LTH contributed technical knowledge of speed breeding; TC, SK, WP, and LTH wrote the manuscript. Acknowledgements: We are grateful to Graeme Wright (Peanut Company of Australia) for providing a photograph of peanut plants growing under speed breeding conditions (Fig. 1a) 2 and Cathie Martin and Abhimanyu Sarkar (John Innes Centre) for providing a photograph of grass pea growing under speed breeding conditions (Fig. 1b). The authors would like to thank the Australian Research Council for support through an Early Career Discovery Research Award to Lee Hickey (DE170101296).

A confined feeding study was conducted to compare the production and physiological effects of feeding three doses of wild-type perennial ryegrass alkaloids via whole seed to Merino sheep housed under thermoneutral conditions (21°C, 50% relative humidity). Eighteen Merino ewe weaners (16 months; initial bodyweight 47 ± 1.94 kg) were offered Nil, Low (50 µg/kg liveweight ergovaline, 22 µg/kg liveweight lolitrem B) or High (100 µg/kg liveweight ergovaline, 44 µg/kg liveweight lolitrem B) doses of alkaloids for 21 days. Dry matter intake tended (P = 0.072) to decrease in a linear manner with increasing dietary alkaloid concentration. Rectal temperature and respiration rate increased (P = 0.002 for both) in a linear manner with increasing dietary alkaloid concentration. Oxygen consumption increased linearly (P = 0.064) and quadratically (P = 0.015) with increasing alkaloid concentration, being highest in the Low dose and intermediate in the High dose group. Plasma prolactin decreased linearly (P = 0.002) with increasing dietary alkaloids. These data clearly show that animal production and efficiency are compromised when sheep consume perennial ryegrass alkaloids, even over a short period of time. This study indicates that a pyrogenic response can occur when alkaloids are consumed, even under thermoneutral conditions.

Simple SummaryPerennial ryegrass endophyte toxicosis in sheep, caused by ingestion of alkaloids, is characterized by staggers and heat stress resulting in poor production or, in some cases, death. This study investigated effects of alkaloid consumption in sheep housed under thermoneutral versus hot ambient temperature on some production and physiological responses. Alkaloid ingestion and extreme heat produced a similar heat stress response and, when combined, this response was exacerbated. Productivity and health and welfare may be compromised when sheep are consuming alkaloids, and this effect is most severe when alkaloid consumption occurs under hot environmental conditions.AbstractA controlled feeding study was undertaken to determine the physiological and production effects of consuming perennial ryegrass alkaloids (fed via seed) under extreme heat in sheep. Twenty-four Merino ewe weaners (6 months; initial BW 30.8 ± 1.0 kg) were selected and the treatment period lasted 21 days following a 14 day acclimatisation period. Two levels of two factors were used. The first factor was alkaloid, fed at a nil (NilAlk) or moderate level (Alk; 80 μg/kg LW ergovaline and 20.5 μg/kg·LW lolitrem B). The second factor was ambient temperature applied at two levels; thermoneutral (TN; constant 21–22 °C) or heat (Heat; 9:00 AM–5:00 PM at 38 °C; 5:00 PM–9:00 AM at 21–22 °C), resulting in four treatments, NilAlk TN, NilAlk Heat, Alk TN and Alk Heat. Alkaloid consumption reduced dry matter intake (p = 0.008), and tended to reduce liveweight (p = 0.07). Rectal temperature and respiration rate were increased by both alkaloid and heat (p < 0.05 for all). Respiration rate increased to severe levels when alkaloid and heat were combined, indicating the short term effects which may be occurring in perennial ryegrass toxicosis (PRGT) areas during severe weather conditions, a novel finding. When alkaloid ingestion and heat were administered separately, similar physiological responses occurred, indicating alkaloid ingestion causes a similar heat stress response to 38 °C heat.

• The reviewed literature suggests that the likely main impact of climate change on New Zealand dairy systems will be a reduction in total annual rainfall and increased inter- and intra-season rainfall and associated soil moisture variability.• Future climate analogues for New Zealand’s current dairying regions are provided from both within New Zealand and Australia.• Future climate scenarios for New Zealand dairy systems can be found within New Zealand with the exception of Northland whose most similar climate analogue is in Australia.• A conceptual framework to increase the boundaries of the ‘zone of system control’ (ZSC) by the farmer is provided here for the first time. The ZSC is defined as the optimal range for a critical input (rainfall or soil moisture in this case) where productive and profitable farming can occur.• Risk of failure increases as the frequency inputs fall above (excess) or below (deficit) the ZSC. Options to reduce the risk of system failure (outside of this zone) are provided with emphasis on soil moisture.• This framework could be used to focus future research and development investment to make the New Zealand and Australian dairy industries more resilient to climate change.

The Australian Legumes Symposium was the first in a planned series of regular technical symposia organised by the Australian Grasslands Association. The aim was to provide researchers with the opportunity to interact, present up-to-date reviews on topics related to pasture legume science, present results of current research and participate in planning of future research and development relevant to pasture legumes. This paper is intended to be the key output of the forum – a summary of findings and highlights from review and contributed research papers as well as identifying key research priorities for the future. In terms of the former, reviews presented at the symposium provided an overview of the development and role of pasture legumes in temperate farming systems. Closely related topics – nitrogen (N) fixation, N balance of farming systems and management of legume inoculation provided a focus on the importance of legumes in terms of N input and overall productivity. International perspectives on lucerne – its improvement and adoption provided a noticeable contrast to the apparent paucity of research into this species in Australia – despite its widespread use in temperate farming systems. In terms of content, there were many other papers delivered dealing with a wide diversity of relevant issues. On one hand the diversity of work in pasture legume research and development may stem from the wide array of expertise available in Australia and New Zealand, while on the other it might suggest that research and development inputs are being thinly spread over a large number of species. With respect to determining research priorities, it was surprising that participants were most concerned with how research is funded and conducted and the need to address this by reconsidering current arrangements. A greater role for economic analysis in determining research priorities was foreshadowed. The identification and management of acid-tolerant perennial legumes for higher rainfall zone permanent pastures was nominated as a major research priority, as was the need to address problems related to pre-inoculation of legume seed. The clear message from the symposium was that there needs to be a reorganisation of pasture legume improvement in order for gains to be effectively realised, and to maintain research and development capacity.