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Simple Summary: Optimal human health requires the adequate provision of all nutrients in the correct proportions, ensuring the provision of energy and essential small molecules. All primates, including humans, are omnivorous but the most striking difference from other primates is the remarkable diversity of the diets we consume. Animal-sourced foods are important for human nutrition and health, but they can have a negative impact on the environment. The aim here is to examine these impacts that can result in land use tensions associated with population growth and the loss of native forests and wetlands during agricultural expansion, increased greenhouse gas emissions, and high water use with poor water quality outcomes. However, several technologies and practices can be used to mitigate against these impacts. These include grazing when feed quality is high, the use of dietary additives, breeding of animals with higher growth rates and increased fecundity, rumen microbial manipulations using vaccines and other additives, soil management to reduce nitrous oxide emission, management systems to improve carbon sequestration, improved nutrient use efficacy, use of cover crops, low-emission composting barns, covered manure storages, and direct injection of animal slurry into soil. Other technologies and systems to provide further solutions continue to be researched. Animal-sourced foods are important for human nutrition and health, but they can have a negative impact on the environment. These impacts can result in land use tensions associated with population growth and the loss of native forests and wetlands during agricultural expansion. Increased greenhouse gas emissions, and high water use but poor water quality outcomes can also be associated. Life cycle analysis from cradle-to-distribution has shown that novel plant-based meat alternatives can have an environmental footprint lower than that of beef finished in feedlots, but higher than for beef raised on well-managed grazed pastures. However, several technologies and practices can be used to mitigate impacts. These include ensuring that grazing occurs when feed quality is high, the use of dietary additives, breeding of animals with higher growth rates and increased fecundity, rumen microbial manipulations through the use of vaccines, soil management to reduce nitrous oxide emission, management systems to improve carbon sequestration, improved nutrient use efficacy throughout the food chain, incorporating maize silage along with grasslands, use of cover crops, low-emission composting barns, covered manure storages, and direct injection of animal slurry into soil. The technologies and systems that help mitigate or actually provide solutions to the environmental impact are under constant refinement to enable ever-more efficient production systems to allow for the provision of animal-sourced foods to an ever-increasing population. [ABSTRACT FROM AUTHOR]

Simple Summary: Optimal human health requires the adequate provision of all nutrients in the correct proportions, ensuring the provision of energy and essential small molecules. All primates, including humans, are omnivorous, but our most striking difference from other primates is the remarkable diversity of diet we consume. The aim here is to examine the benefits and possible unintended consequences of using herbivore-based foods on human and animal health and welfare. The advantages of using grazed pasture for ruminant meat and milk production include (1) animal-sourced foods contain essential amino acids and micronutrients, and almost always have a higher digestibility than plant proteins, (2) greater use of pasture to feed animals could result in less use of food that could be used for human consumption, e.g., maize, soybean, and cereal crops, (3) ruminants can provide food from land otherwise unable to be used for cropping, consume feed that cannot be eaten directly by humans, and provide more than just food—they also provide leather and fibre. Animal-sourced foods are an important part of the human diet, and while some unintended consequences associated with animal health and herd management have occurred, technologies and systems to provide solutions to these are available and under refinement. Human health and diet are closely linked. The diversity of diets consumed by humans is remarkable, and most often incorporates both animal and plant-based foods. However, there has been a recent call for a reduced intake of animal-based foods due to concerns associated with human health in developed countries and perceived impacts on the environment. Yet, evidence for the superior nutritional quality of animal-sourced food such as meat, milk, and eggs, compared with plant-based foods, indicates that consumption of animal-sourced food should and will continue. This being the case, the aim here is to examine issues associated with animal-sourced foods in terms of both the quantification and mitigation of unintended consequences associated with environment, animal health, and herd management. Therefore, we examined the role of animal proteins in human societies with reference to the UN-FAO issues associated with animal-sourced foods. The emphasis is on dominant grazed pastoral-based systems, as used in New Zealand and Ireland, both with temperate moist climates and a similar reliance on global markets for generating net wealth from pastoral agricultural products. In conclusion, animal-sourced foods are shown to be an important part of the human diet. Production systems can result in unintended consequences associated with environment, animal health, and herd management, and there are technologies and systems to provide solutions to these that are available or under refinement. [ABSTRACT FROM AUTHOR]

Food and feed has been produced from genetically modified (GM) crops for 25 years. It is timely to review whether this technology has globally delivered the expected benefits and whether the ongoing debate on risks is justified. Expected benefits associated with GM include increased crop yields, reduced pesticide and insecticide use, reduced carbon dioxide emissions, improved soil structure, improved crop nutritive quality/value, and decreased costs of production. Concerns focus on food safety linked to toxicity and allergenicity, environmental risks associated with potential chances of gene flow, adverse effects on non-target organisms, evolution of resistance in weeds and insects, and genetic perturbations resulting in unintended compounds, new diseases, or antibiotic resistance. This review focusing on benefits and risks of GM crops concludes that they are a valuable option for delivering improved economic and environmental outcomes by providing solutions for many of the challenges facing mankind. GM technologies like many non-GM technologies can bring risks, but these can and have been monitored and quantified, allowing decisions balancing commercial, societal and environmental benefits against measurable risks. While 'checks' and 'balances' are required, regulatory schemes must focus on balancing risks and benefits and not on 'checks' alone which is the case for many countries. [ABSTRACT FROM AUTHOR]

Perennial ryegrass (Lolium perenne L.) remains the predominant grazed grass in New Zealand’s pastoral agriculture. Brought in from Europe in the early nineteenth century, locally adapted populations or ecotypes developed in a number of regions. Government plant breeders, employed to provide elite cultivars for farmer use as a public good, exploited an ecotype from the Hawke’s Bay region to produce ‘Grasslands Ruanui’. In the1950s Trevor Ellett, a dairy farmer in Mangere, Auckland noted that Grasslands Ruanui did not persist as well as ryegrass sown with seed harvested from 40 to 60 year old paddocks on his own farm. This ecotype, referred to as Mangere ryegrass, has since become the basis of many ryegrass cultivars bred by both government and commercial plant breeders over the past 50 years. This review documents how Mangere ryegrass became an important part of ryegrass cultivar development, the part it played in commercial plant breeders becoming involved in cultivar development, and coincidently in the discovery that the Epichloë fungal endophyte is crucial for perennial ryegrass persistence under drought, heat and insect pressure. [ABSTRACT FROM AUTHOR]

The New Zealand economy is export-driven and heavily reliant on the productivity of the pastoral sector. The transformation of native forest and tussock grassland ecologies to temperate grasslands occurred rapidly with the arrival of Europeans. However, this transplanted ecology required the development and use of plant, microbial, animal and management technologies for successful grassland farming. These have enabled New Zealand pastoral agriculture to compete effectively in international markets, without subsidies. The extensive list of plant-based and associated microbial-based adaptations, and the management strategies that have enabled the development of highly productive grasslands are described and reviewed. Credible science is required to inform the debate on the environmental impacts of pasture production to avoid misinformation proliferating. This needs transparent and objective integrity from the science community using funding that seeks no defined or preconceived outcomes. Critically, much of the success of New Zealand pastoral farming has been due to the willingness and ability of farmers to use, adapt, adopt and integrate new ideas and technologies into their farming systems. Historic, current and future challenges, and threats that impact on the productivity and sustainability of pastoral agriculture are described and the means to achieve further technology development to manage these is discussed. [ABSTRACT FROM AUTHOR]

Plant breeding has been closely aligned with the development of civilisations and continues to be important for the supply of nutritious food and a key factor in reducing poverty and hunger. Plant breeding uses a range of techniques for both expanding and exploiting the genetic potential of plants. However, some techniques are deemed higher risk than others despite the end products of both processes at times being indistinguishable. While it is considered that the domestication of some plant species began over 10,000 years ago, it is only in the last 100 years or so that modern plant breeding has been used to develop thousands of cultivars in a range of plant species for food, feed, and recreation. In the last 25 years, genetic modification and, more recently, New Breeding Technologies have been used to introduce new variations into important plant species. This has resulted in mistrust and suspicion, and a range of regulatory systems. Product-based and process-based regulatory systems differ in the information required for decision-making. Methods used for the development and manipulation of plant traits are reviewed in an attempt to understand the reasons why some are deemed more acceptable than others. [ABSTRACT FROM AUTHOR]

Pastoral agriculture underpins the New Zealand economy. Its success in generating export income is due to a mild and moist temperate climate, productive soils, innovative farmers supported by an effective research and development system, and an energy efficient production system based on year-round grazing. However, pastoral agriculture is entirely reliant on introduced pasture and forage species and their ability to withstand both endemic and introduced pasture pests. Critical to this is the mutualistic relationship between ryegrass and Epichloë fungal endophytes which provide a range of secondary metabolites that deter herbivory by both ruminants and insect pests. The challenge has been to identify and commercialise Epichloë strains which while providing protection against insect pests, ensuring ryegrass persistence, do not cause animal health and welfare issues. The critical role that Epichloë fungal endophytes play in maintaining pasture persistence and as a result the pastoral economy of New Zealand will be reviewed. [ABSTRACT FROM AUTHOR]

Innovation in agriculture has been essential in improving productivity of crops and forages to support a growing population, improving living standards while contributing toward maintaining environment integrity, human health, and wellbeing through provision of more nutritious, varied, and abundant food sources. A crucial part of that innovation has involved a range of techniques for both expanding and exploiting the genetic potential of plants. However, some techniques used for generating new variation for plant breeders to exploit are deemed higher risk than others despite end products of both processes at times being for all intents and purposes identical for the benefits they provide. As a result, public concerns often triggered by poor communication from innovators, resulting in mistrust and suspicion has, in turn, caused the development of a range of regulatory systems. The logic and motivations for modes of regulation used are reviewed and how the benefits from use of these technologies can be delivered more efficiently and effectively is discussed. [ABSTRACT FROM AUTHOR]

Forage legumes such as white and red clover improve the nutritional quality of grazed pasture but can cause bloat. Their rapid fermentation in the rumen also contributes to environmental issues through higher methane emissions and urinary nitrogen losses. Condensed tannins are known to reduce urinary nitrogen and methane production from grazing animals, reduce bloat, reduce internal parasite burden, and improve animal productivity. Several forage legumes including birdsfoot trefoil and sainfoin do have good levels of condensed tannins but unfortunately these species fail to persist in intensively grazed pasture systems. Conventional breeding approaches including mutagenesis and phenotypic selection have failed to deliver condensed tannins in legumes, such as white clover, red clover or lucerne, that do persist under grazing. A recent advance using a molecular biology approach has identified a transcription factor or master switch that can 'turn on' the condensed tannin pathway present in white clover allowing biologically significant levels of condensed tannin expression in leaf tissue. In vitro tests have demonstrated that the condensed tannins produced in white clover leaves can bind protein at a pH 6.5, as found in the rumen, and then release them at pH 2.5, the pH in the abomasum, before entering the small intestine for amino acid absorption. Additional tests have demonstrated that these condensed tannins can reduce methane production by up to 15.7% in the first 6 h of incubation. The journey to this point, and the challenges ahead to deliver white clover cultivars with condensed tannin expression, is described. [ABSTRACT FROM AUTHOR]

In identifying endophytes for use in pastures in New Zealand there have been two strategies used, either exclusion of ergopeptine and lolitrem alkaloids or, retaining some ergopeptine expression to enhance the stability of natural defences against invertebrate pests. Both have their strengths and weaknesses. It is a matter of balancing these to ensure the end-user has access to a product that satisfies their needs – a persistent pasture with low to nil animal toxicity in terms of animal production and welfare. The range and intensity of ergot alkaloids in grazed pasture on both pasture and ruminants is reviewed, with emphasis on New Zealand. Ergot alkaloids associated with pasture are produced by associations between certain Epichloë endophyte strains and temperate grasses. Ergot alkaloids have been shown to improve persistence of pasture through providing resistance/deterrence to insect pests as well as deterring grazing animals. However, ergovaline is toxic to grazing animals. Some commercially available ryegrass-endophyte associations can produce ergovaline concentrations close to those found in associations between ryegrass and the standard endophyte. It is feasible to eliminate ergot alkaloids from pasture grasses in New Zealand as endophyte strains are commercially available that do not express ergovaline and yet still provide excellent pest resistance. [ABSTRACT FROM AUTHOR]

Definition: Asexual Epichloë are obligate fungal mutualists that form symbiosis with many temperate grass species, providing several advantages to the host. These advantages include protection against vertebrate and invertebrate herbivores (i.e., grazing livestock and invertebrate pests, respectively), improved resistance to phytopathogens, increased adaptation to drought stress, nutrient deficiency, and heavy metal-containing soils. Selected Epichloë strains are utilised in agriculture mainly for their pest resistance traits, which are moderated via the production of Epichloë-derived secondary metabolites. For pastoral agriculture, the use of these endophyte infected grasses requires the balancing of protection against insect pests with reduced impacts on animal health and welfare. [ABSTRACT FROM AUTHOR]

The relationship between Epichloë endophytes found in a wide range of temperate grasses spans the continuum from antagonistic to mutualistic. The diversity of asexual mutualistic types can be characterised by the types of alkaloids they produce in planta. Some of these are responsible for detrimental health and welfare issues of ruminants when consumed, while others protect the host plant from insect pests and pathogens. In many temperate regions they are an essential component of high producing resilient tall fescue and ryegrass swards. This obligate mutualism between fungus and host is a seed-borne technology that has resulted in several commercial products being used with high uptake rates by end-user farmers, particularly in New Zealand and to a lesser extent Australia and USA. However, this has not happened by chance. It has been reliant on multi-disciplinary research teams undertaking excellent science to understand the taxonomic relationships of these endophytes, their life cycle, symbiosis regulation at both the cellular and molecular level, and the impact of secondary metabolites, including an understanding of their mammalian toxicity and bioactivity against insects and pathogens. Additionally, agronomic trials and seed biology studies of these microbes have all contributed to the delivery of robust and efficacious products. The supply chain from science, through seed companies and retailers to the end-user farmer needs to be well resourced providing convincing information on the efficacy and ensuring effective quality control to result in a strong uptake of these Epichloë endophyte technologies in pastoral agriculture. [ABSTRACT FROM AUTHOR]

Background: Microbial endophytes can be beneficial to host plants, improving resistance against biotic and abiotic stress. While beneficial fungal endophytes have been well characterised in temperate grasses, knowledge about fungal endophytes of tropical grasses is limited. Aims: We investigated the diversity of fungal endophytes associated with Brachiaria, a tropical grass genus native to Africa to source candidate endophytes for developing as beneficial inoculants for cultivated Brachiaria. Methods: Fungi were isolated from asymptomatic tillers of nine Brachiaria species. Morphological and molecular techniques were used to investigate the taxonomic identities and phylogenetic relationships of the putative fungal endophytes. Results: One hundred and seventy-seven fungi were isolated, generating 38 operational taxonomic units (OTU) in total, which were predicted to represent 38 potential species. The most common isolates were related to Acremonium, Cladosporium, Emericellopsis, Plectosphaerella and Sarocladium. Multiple strains of Sarocladium terricola were detected and shown by molecular and morphological characterisation as identical to the first recorded seed-transmitted endophyte from Brachiaria, originally identified as Acremonium implicatum. Conclusion: A large and genetically diverse collection of putative endophytes from Brachiaria have been identified. Future work will elucidate whether any of these could be developed as beneficial endophyte inoculations able to offer bio-protective benefits for the health of Brachiaria. [ABSTRACT FROM AUTHOR]

Science ensures that explanations and predictions about the biological and physical worlds are verifiable, while also providing an approach that enables improved understanding to develop and be permanently recorded. There are several terms in common usage that describe the approaches used in scientific research, but at the extremes, words such as ‘reductionism’ and ‘holism’ are now frequently encountered. While singular reductionism can result in key relationships and linkages being missed, holism appears to ignore the need to identify how confounding factors can affect the quality of understanding derived from complex systems. Here we suggest that science is not a simple dichotomy of reductionism versus holism. Instead, it comprises a more fluid and complex mission. However, within multidisciplinary agricultural and horticultural science one regularly finds words like ‘systems’, ‘integration’, and ‘unifying’. Reductionist science is certainly part of the pursuit of holistic solutions to problems, not least in transdisciplinary research. [ABSTRACT FROM AUTHOR]

This minireview highlights the importance of endophytic fungi for sustainable agriculture and horticulture production. Fungal endophytes play a key role in habitat adaptation of plants resulting in improved plant performance and plant protection against biotic and abiotic stresses. They encode a vast variety of novel secondary metabolites including volatile organic compounds. In addition to protecting plants against pathogens and pests, selected fungal endophytes have been used to remove animal toxicities associated with fungal endophytes in temperate grasses, to create corn and rice plants that are tolerant to a range of biotic and abiotic stresses, and for improved management of post-harvest control. We argue that practices used in plant breeding, seed treatments and agriculture, often caused by poor knowledge of the importance of fungal endophytes, are among the reasons for the loss of fungal endophyte diversity in domesticated plants and also accounts for the reduced effectiveness of some endophyte strains to confer plant benefits. We provide recommendations on how to mitigate against these negative impacts in modern agriculture. [ABSTRACT FROM AUTHOR]

Epichloë is a genus of filamentous fungal endophytes that have co-evolved with cool-season grasses with which they form long-term, symbiotic associations. In natural ecosystems Epichloë have implications for species diversity, food web structures and fundamental ecological processes. Epichloë produce a range of secondary metabolites that can have negative effects on herbivores, be they invertebrates or vertebrates. In many managed pastoral systems, selected asexual Epichloë strains are purposefully associated with grass cultivars (termed novel endophyte-grass associations) as they confer beneficial traits that protect the host from abiotic stresses (e.g. drought) and biotic stresses (e.g. herbivory from invertebrates) while having minimal impact on the health and welfare of ruminant livestock. As well as conferring beneficial traits, agriculturally selected strains of Epichloë can also increase plant biomass and seed yield. Epichloë endophyte-technology has and continues to be a scientific, agricultural, and marketing success with selected asexual strains of Epichloë now essential components of many pasture ecosystems, within New Zealand and abroad. An estimated 90% of proprietary ryegrass now sold in New Zealand contains a selected endophyte strain while the economic impact in New Zealand of AR37 alone has been estimated at NZ$3.6 billion over 20 years. With a changing climate, agriculture will continue to experience increasing temperatures, elevated atmospheric CO2 levels and changing precipitation patterns that will likely increase the geographic range and overwintering survival rates of pests. Furthermore, plant disease outbreaks are expected to intensify due to increases in the severity of existing phytopathogens and/or invasions by new phytopathogens. Functional symbioses, such as those between temperate grasses and Epichloë, are among the most successful mechanisms by which plants can improve their ability to tolerate stress. Future research is likely to utilise targeted genetic manipulation techniques to broaden the biocontrol ability of Epichloë strains, particularly to mitigate climate related stresses. [ABSTRACT FROM AUTHOR]

New Zealand's intensive pastures, comprised almost entirely introduced Lolium L. and Trifolium L. species, are arguably the most productive grazing-lands in the world. However, these areas are vulnerable to destructive invasive pest species. Of these, three of the most damaging pests are weevils (Coleoptera: Curculionidae) that have relatively recently been controlled by three different introduced parasitoids, all belonging to the genus Microctonus Wesmael (Hymenoptera: Braconidae). Arguably that these introduced parasitoids have been highly effective is probably because they, like many of the exotic pest species, have benefited from enemy release. Parasitism has been so intense that, very unusually, one of the weevils has now evolved resistance to its parthenogenetic parasitoid. This review argues that New Zealand's high exotic pasture pest burden is attributable to a lack of pasture plant and natural enemy diversity that presents little biotic resistance to invasive species. There is a native natural enemy fauna in New Zealand that has evolved over millions of years of geographical isolation. However, these species remain in their indigenous ecosystems and, therefore, play a minimal role in creating biotic resistance in the country's exotic ecosystems. For clear ecological reasons relating to the nature of New Zealand pastures, importation biological control can work extremely well. Conversely, conservation biological control is less likely to be effective than elsewhere. [ABSTRACT FROM AUTHOR]