Lower Input Systems Research Articles

Comparison of three maternal composite sheep breeds managed under pasture lambing and purebred or terminal mating systems: ewe body weight, reproductive efficiency, and longevity.

Extensive sheep systems have lower inputs (e.g., feed, labor, infrastructure) but, generally, lower outputs per ewe than intensively managed flocks. Average ewe prolificacy is low (< 1.1 lambs per ewe) across the United States and traditional expectation is that costs required to support larger litters will not be recovered due to greater lamb mortality. The Composite-IV (C-IV) is a 50% Romanov, 25% Katahdin, and 25% White Dorper hair sheep developed and selected for enhanced reproductive efficiency at the U.S. Meat Animal Research Center. Objectives of the current study were to compare productivity of C-IV ewes (N = 404) to Katahdin (N = 342) and Polypay (N = 390), two popular maternal composite breeds, in a lower-input system. Experimental ewes were exposed to either rams of their own breed or Texel rams for the first time at 7 mo of age and remained in the same mating system for up to 4 yr. Ewes lambed on pasture from May to June and were expected to rear their lambs in the absence of supplemental feed and with minimal intervention. The ewe age × breed interaction effect impacted all annually recorded traits (P < 0.01) including number and total weight of lamb marketed at 25 wk per ewe exposed to mating (LS25 and LW25, respectively). Within all ages, LS25 of C-IV was greater (1.2 to 1.63 lambs; P < 0.01) than Katahdin (0.71 to 1.17 lambs) and Polypay (0.68 to 1.26 lambs) which were similar. At 1, 2, and 3-yr of age, C-IV ewes had, on average, 12 to 17 kg greater LW25 (P ≤ 0.01) than other breeds. Polypay LW25 was similar to Katahdin at 1 yr of age, but 8 to 13 kg greater (P < 0.01) at older ages. At 4 yr of age, LW25 was similar for C-IV and Polypay (63 and 62 kg, respectively). Overall, Texel mating improved LW25 by 3 kg compared to purebred mating (P < 0.01). Twin litters were most common within mature ewes (> 1 yr) of all breeds (52% to 65%); however, the proportion of triplet litters was numerically greater for C-IV (13%) than Katahdin (1%) or Polypay (4%). The frequency of mature ewes that gave birth to and reared twins (75% to 82%) was high for all breeds. Most triplet-bearing mature C-IV ewes reared twins (43%) though many reared triplets (39%). Ewe reproductive efficiency can be enhanced in lower-input systems by utilizing additive breed effects and heterosis in a complimentary crossbreeding program. More research is needed to identify indicator traits associated with lamb survival and to derive appropriate levels of prolificacy to fit specific management constraints.

Fertilizer quantity and type alter mycorrhizae‐conferred growth and resistance to herbivores

Abstract Plants face a constant struggle to acquire nutrients and defend themselves against herbivores. Mycorrhizae are fungal mutualists that provide nutrients that can increase plant growth and alter resistance to herbivores. The beneficial effects of mycorrhizae for nutrient acquisition can depend on the quantity and type of soil nutrients available, with plants usually benefiting more in terms of growth from mycorrhizae when nutrients are limited. However, it is unclear how the addition of different nutrients might shift mycorrhizal‐conferred resistance to herbivores by changing defensive secondary chemistry and nutrient availability. We conducted two concurrent greenhouse experiments to test how three levels of fertilizers (low, medium and high) and three types of fertilizers (organic, organically derived and inorganic) altered mycorrhizae‐conferred resistance to herbivores in tomato plants. In addition, we looked at whether mycorrhizae‐conferred resistance was driven by plant secondary metabolites or the nutrient content of the leaves. Association with mycorrhizae was associated with an increase in biomass at low levels of fertilization and decreased biomass at high levels of fertilization. Interestingly, mycorrhizae increased resistance to herbivores at medium levels of fertilization, but had no effect at low and high levels of fertilization. Mycorrhizae improved resistance most strongly when plants were fertilized with a phosphorus rich, organically derived fertilizer. In both experiments, increased resistance was correlated with changes in the plant's foliar nitrogen content. Synthesis and applications. Our study supports the potential for mycorrhizae to improve either crop growth or pest resistance under lower fertilizer conditions. However, mycorrhizae did not provide both growth and resistance benefits under any treatment. While mycorrhizae have the potential to benefit crops in in lower input systems, it may be challenging to maximize both growth and resistance benefits.

Pasture-Based Dairy Systems in Temperate Lowlands: Challenges and Opportunities for the Future

Improved efficiency in dairy systems is a significant challenge for the future, to meet increased food demand while competing for inputs, adapting to climate change, and delivering ecosystem services. Future grazing systems can play a major role to supply healthier foods within systems with a reduced reliance on fossil fuels and chemical inputs, while also delivering environmental, biodiversity, and animal welfare benefits. Can we design lower-input systems that deliver efficient levels of output in a positive environmental context? Lower-input systems will have a lower reliance on concentrates and inorganic fertilizers, and an increased reliance on extended grazing seasons and high quality forage. Multiple strategies will be needed to maximize nitrogen use efficiency, including a strong reliance on legume-based swards that displace inorganic nitrogen fertilizer. Expected environmental benefits include a reduction in GHG emissions and nitrate leaching, an increase in C sequestration and a reduced reliance on the use of herbicides and pesticides. In comparison with confinement feeding systems, the relatively low energy density and high climate sensitivity of grazing diets requires both effective pasture management and robust and adaptive animals. The appropriate cow for grazing systems must be able to harvest pasture efficiently by re-calving every 365 days to efficiently utilize peak pasture supply, achieve large intakes of forage relative to their genetic potential for milk production (i.e., aggressive grazers) and be adaptable to fluctuations in feed supply. Legume-based multi-species grassland mixtures can maximize the use of symbiotically-fixed nitrogen, and displace the use of inorganic N fertilizer. There is a need for system-scale experiments that use legume-based mixtures within paddocks, and in grassland leys within crop rotations. Moreover, lower-input systems will need a combined focus on research and knowledge transfer for rapid testing and implementation. New opportunities and requirements will arise as policy, society, and the markets demand a higher level of environmental sustainability from food systems and products. This raises the possibility of public-private partnerships for the demand and reward of provision of environmental benefits. To deliver these benefits, future food systems will need to be redesigned to incorporate the enhanced supply of a range of ecosystem goods and services, which should be better incentivized through the market price returned to producers.

Benefits and Trade-Offs of Dairy System Changes Aimed at Reducing Nitrate Leaching.

Simple SummaryReducing inputs of nitrogen fertiliser and purchased feed, with an associated reduction in stocking rate on pastoral dairy farms resulted in less nitrate leaching. A co-benefit was a reduction in greenhouse gas emissions. The exception was the implementation of a wintering barn where nitrate leaching was reduced, but greenhouse gas emissions remained unchanged due to greater manure storage and handling. Emission reductions in the lower-input systems came at an average loss of profit of approximately NZ$100 per tonne CO2-equivalent.Between 2011 and 2016, small-scale farm trials were run across three dairy regions of New Zealand (Waikato, Canterbury, Otago) to compare the performance of typical regional farm systems with farm systems implementing a combination of mitigation options most suitable to the region. The trials ran for at least three consecutive years with detailed recording of milk production and input costs. Nitrate leaching per hectare of the milking platform (where lactating cows are kept) was estimated using either measurements (suction cups), models, or soil mineral nitrogen measurements. Post-trial, detailed farm information was used in the New Zealand greenhouse gas inventory methodology to calculate the emissions from all sources; dairy platform, dairy support land used for wintering non-lactating cows (where applicable) and replacement stock, and imported supplements. Nitrate leaching was also estimated for the support land and growing of supplements imported from off-farm using the same methods as for the platform. Operating profit (NZ$/ha/year), nitrate leaching (kg N/ha/year), and greenhouse gas emissions (t CO2-equivalent/ha/year) were all expressed per hectare of milking platform to enable comparisons across regions. Nitrate leaching mitigations adopted in lower-input (less purchased feed and nitrogen fertiliser) farm systems reduced leaching by 22 to 30 per cent, and greenhouse gas emissions by between nine and 24 per cent. The exception was the wintering barn system in Otago, where nitrate leaching was reduced by 45 per cent, but greenhouse gas emissions were unchanged due to greater manure storage and handling. Important drivers of a lower environmental footprint are reducing nitrogen fertiliser and purchased feed. Their effect is to reduce feed flow through the herd and drive down both greenhouse gas emissions and nitrate leaching. Emission reductions in the lower-input systems of Waikato and Canterbury came at an average loss of profit of approximately NZ$100/t CO2-equivalent (three to five per cent of industry-average profit per hectare).

Higher Intensity, Higher Profit? Empirical Evidence from Dairy Farming in New Zealand

AbstractOver the last two decades there have been significant and well‐documented changes in the nature and structure of New Zealand dairy production. One particular feature has been a marked shift in the ‘input intensity’ of dairy farming systems through increased use of supplementary feed. These changes have generated debate about the impact of dairy farm intensity on the performance of farm businesses and the competitiveness of the New Zealand dairy sector. Using a novel econometric approach, we assess statistically the impact of three types of dairy farming systems on milk production and financial performance, using farm business data provided by DairyBase®. Our empirical results show that higher input systems perform significantly better physically than lower input systems, but not financially. The disaggregated analysis suggests that the average treatment effects differ by region and performance quantiles.

Sensitivity of the carbon footprint of New Zealand milk to greenhouse gas metrics

Milk production is responsible for emitting a range of greenhouse gases (GHGs), mainly carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). In Life Cycle Assessments (LCA), the Global Warming Potential with a time horizon of 100 years (GWP100) is used almost universally to aggregate emissions of individual gases into so-called CO2-equivalent emissions that are used to calculate the overall carbon footprint of milk production. However, there is growing awareness that, depending on the purpose of the LCA, metrics other than GWP100 could be justified and some would give a very different weighting for the short-lived gas CH4 relative to the long-lived gases CO2 and N2O when calculating the carbon footprint. Pastoral dairy production systems at different levels of intensification differ in the balance of short- and long-lived GHGs associated with on- and off-farm emissions. Differences in the carbon footprint of different production systems could therefore be highly sensitive to the choice of GHG metric. Here we explore the extent to which alternative GHG metric choices would alter the carbon footprint of New Zealand milk production at different levels of intensification at national, regional and individual farm scales and compared to the carbon footprint of milk of selected European countries. We find that the ranking of different production systems and individual farms in terms of their carbon footprint is relatively robust against the choice of GHG metric, despite significant differences in their utilisation of pastures versus supplementary off-farm feed, fertiliser use and energy consumption at various stages of farm operations. However, there are instances where alternative GHG metric choices would fundamentally change the conclusions of LCA of different production systems, including whether a move towards higher or lower input systems would increase or decrease the average carbon footprint of milk production in New Zealand. Greater transparency about the implications of alternative GHG metrics for LCA, and the often inadvertent and implicit value judgements embedded in these metrics, would help ensure that policy decisions and consumer choices based on LCA indeed deliver the climate outcomes intended by end-users.

An analysis of the energy efficiency of winter rapeseed biomass under different farming technologies. A case study of a large-scale farm in Poland

The article presents the results of a three-year study investigating the impact of production technology on the energy efficiency of winter rapeseed produced in large-scale farms. Rapeseed biomass produced in a high-input system was characterized by the highest energy demand (30.00 GJ ha−1). The energy demand associated with medium-input and low-input systems was 20% and 34% lower, respectively. The highest energy value of oil, oil cake and straw was noted in winter rapeseed produced in the high-input system. In the total energy output (268.5 GJ ha−1), approximately 17% of energy was accumulated in oil, 20% in oil cake, and 63% in straw. In lower input systems, the energy output of oil decreased by 13–23%, the energy output of oil cake – by 6–16%, and the energy output of straw – by 29–37% without visible changes in the structure of energy accumulated in different components of rapeseed biomass. The highest energy gain was observed in the high-input system. The low-input system was characterized by the highest energy efficiency ratio, at 4.22 for seeds and 9.43 for seeds and straw. The increase in production intensity reduced the energy efficiency of rapeseed biomass production by 8–18% (seeds) and 5–9% (seeds and straw).

Hybrid Tomato Breeding

Summary Tomato is one of the most popular vegetable crops grown across the world. Its genetics is much studied among vegetable crops, resulted in the reorganization of its commercial exploitation of hybrid vigor since last hundred years. Tomato has tremendous potential of heterosis for earliness, total yield, resistance attributes and uniformity. Hybrid tomato varieties will continue to predominate high input agricultural systems and may expand under some lower input systems where benefits can be demonstrated. Increasing demand for hybrid seeds can stress commercial hybrid seed production abilities. At present most of the hybrid seeds of tomato is being produced by hand emasculation and hand pollination. The advances in genetic emasculation methods can prove very useful for making the hybrid seed production profitable and ensure the supply of hybrid seed at cheaper rates to the growers.

Functional aspects of soil animal diversity in agricultural grasslands

There has been recent interest in the characterization of soil biodiversity and its function in agricultural grasslands. Much of the interest has come from the need to develop grassland management strategies directed at manipulating the soil biota to encourage a greater reliance on ecosystem self-regulation. This review summarises information on selected groups of soil animals in grasslands, the factors influencing their abundance, diversity and community structure and their relationships to the functioning and stability of grassland ecosystems. Observations on the impacts of agricultural managements on populations and communities of soil fauna and their interactions confirm that high input, intensively managed systems tend to promote low diversity while lower input systems conserve diversity. It is also evident that high input systems favour bacterial-pathways of decomposition, dominated by labile substrates and opportunistic, bacterial-feeding fauna. In contrast, low-input systems favour fungal-pathways with a more heterogeneous habitat and resource leading to domination by more persistent fungal-feeding fauna. In view of this, we suggest that low input grassland farming systems are optimal for increasing soil biotic diversity and hence self-regulation of ecosystem function. Research is needed to test the hypothesis that soil biodiversity is positively associated with stability, and to elucidate relationships between productivity, community integrity and functioning of soil biotic communities.

Sustainable agriculture in the Corn Belt: Production-side progress and demand-side constraints

AbstractThis paper explores the constraints to sustainable agriculture in the Com Belt stemming from the trend toward increased farm size and the continued dependence of the region on undifferentiated farm commodities produced for regional, national, and international markets. It is based on a three-county comparison of 14 full-time farmers who have embraced sustainable principles and practices, and a randomly sampled group of 25 farmers. An encouraging finding was the substantial progress made towards lower-input production of com and soybeans by the nine farmers who had adopted the ridge tillage system, which uses elevated seedbeds, banded herbicides, and post-plant nitrogen application to reduce both soil erosion and synthetic chemical inputs while maintaining yields. However, operators of large farms that depend on hired labor and highly dispersed field sites regarded these practices as too risky at their scale of production despite their short-term economic and long-term environmental benefits. The region's commercial farmers appear split between family farmers who wish to avoid the headaches of scale expansion and hired labor, and therefore, embrace more efficient low-input systems such as ridge tillage versus those who reject the increased management intensity and risks of lower-input systems in favor of scale expansion via more chemical-intensive no-till systems. Although ridge tillage represents movement toward low-input cash grain production, low-input production systems alone are not sufficient to improve the underlying social welfare of rural areas. Arresting the trend towards fewer and larger farms will also require development of more specialized or more localized markets for sustainably produced commodities.

The effect of increased inputs to twin-bearing ewes within an extensive hill sheep system

There is a general belief that reduced stock numbers on hill areas will be beneficial to the environment. A decrease in stock numbers may lead to farmers opting for lower input systems of hill sheep production in order to reduce costs, to meet the requirements of specific schemes or simply to maintain profitability. A large scale systems experiment has been set up at SAC Kirkton and Auchtertyre Farms to examine the effects of extensification on the ecology, animal production and welfare and the socio-economics of the local community. Within this extensive system, a 4-year trial was undertaken to examine the effects of a limited increase in inputs to twin-bearing ewes which are particularly at risk within such a system.

The effect of increased inputs to twin-bearing ewes within an extensive hill sheep system

There is a general belief that reduced stock numbers on hill areas will be beneficial to the environment. A decrease in stock numbers may lead to farmers opting for lower input systems of hill sheep production in order to reduce costs, to meet the requirements of specific schemes or simply to maintain profitability. A large scale systems experiment has been set up at SAC Kirkton and Auchtertyre Farms to examine the effects of extensification on the ecology, animal production and welfare and the socio-economics of the local community. Within this extensive system, a 4-year trial was undertaken to examine the effects of a limited increase in inputs to twin-bearing ewes which are particularly at risk within such a system.

Comparative local economic benefits of conventional and alternative cropping systems

AbstractI reexamined five previously published studies that compared the economics of high input conventional crop production systems in various regions to the economics of lower input alternatives that use green manures, cover crops, and more diversified rotations, but no inorganic fertilizers and little or no synthetic pesticides. The original analyses were extended to include estimates of each production system's contribution to the local economy, both directly through farmers' payments for labor and interest, and indirectly through the payrolls and profits of enterprises serving farmers. A similar comparison was also made for high input irrigated and lower input nonirrigated corn production. On a per acre basis, the high input systems' local economic benefits were equal to or greater than those of the lower input systems. However, they were lower as a fraction of total value of production in all but one case, since production was always higher for the higher input systems. Correspondingly, with all but one of the higher input systems, a greater portion of the value of production left the local economy to pay for purchased inputs. This becomes significant if the production system is not sustainable, so that the total productive potential of the area's agricultural resources is finite when integrated over their entire economic life. In such circumstances, the results imply that under the conventional system the local economy will capture a smaller share of the total productive value of those resources.

The concept of integrated systems in lower input/sustainable agriculture

AbstractConventional agriculture has caused economic problems associated with overproduction of crops, increased costs of energy-based inputs and lessened farm incomes. It has also produced ecological problems such as poor ecological diversity, soil erosion, and soil and water pollution. The adoption of integrated systems of agricultural production involving lower inputs of fertilizer, pesticides and cultivations can alleviate these economic and ecological problems. Such systems are dependent upon a good understanding of the nature of interactions between the four main components of such systems, which are fertilizers, pesticides, cultivations and rotations and how these interactions influence crop yields and farm income. Alternatives to energy-based inputs include legume rotations, use of waste organic matter as well as that from animals and crops, integrated pest management, pest and disease forecasting, biological and cultural pest control, living mulches and mechanical weed control, conservation tillage methods, and specialized innovative cultural techniques, including intercropping, strip cropping, undersowing, trap crops, double-row cropping. Two commercial farms in Europe operated on integrated lower input systems have increased farm incomes by 5–20 percent. Further research on such techniques is needed, as well as computer-aided management systems, appropriate extension aids and farmer education.