Review
Plant Sciences
Alain Gojon, Oceane Cassan, Lien Bach, Laurence Lejay, Antoine Martin
Summary: Elevated atmospheric CO2 concentration negatively affects C3 plant physiology beyond photosynthesis and carbon metabolism, leading to reduced mineral nutrient concentrations in plant tissues. This poses significant threats to crop quality, nutrient cycles, and carbon sinks in terrestrial agro-ecosystems. The detrimental effect on plant mineral status, particularly nitrogen, is associated with the direct inhibition of key mechanisms of nitrogen uptake and assimilation. Promising strategies for identifying genotypes that can maintain robust nutrient status in a high-CO2 world are also discussed.
TRENDS IN PLANT SCIENCE
(2023)
Article
Engineering, Environmental
Ling-Dong Shi, Qiu-Jin Xu, Jie-Yi Liu, Zi-Xian Han, Yong-Guan Zhu, He-Ping Zhao
Summary: The study demonstrates that the addition of selenate significantly increases the abundance of antibiotic resistance genes (ARGs), with ARGs resistant to multiple drugs showing similar co-occurrence patterns, posing a greater health risk. It also enhances the vertical transfer and horizontal gene transfer of ARGs.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Biochemistry & Molecular Biology
Jun-Song Li, Nobuo Suzui, Yuji Nakai, Yon-Gen Yin, Satomi Ishii, Shu Fujimaki, Naoki Kawachi, Hiroki Rai, Takashi Matsumoto, Kanna Sato-Izawa, Naoko Ohkama-Ohtsu, Shin-ichi Nakamura
Summary: The study found that glutathione can inhibit the translocation of cadmium from plant roots to shoots, and by activating the inward return process of cadmium, it promotes this inhibitory effect. Experimental results demonstrate the important role of the shoot base in distributing cadmium throughout the plant body. Microarray analysis revealed that about 400 genes in the roots responded to root-applied glutathione.
Article
Plant Sciences
Konrad Kraemer, Gabi Kepp, Judith Brock, Simon Stutz, Arnd G. Heyer
Summary: Plants exposed to elevated CO2 initially show increased photosynthetic activity, but this declines over time. The decline is associated with an increase in the carbon-to-nitrogen ratio of the biomass. The study demonstrates that reduced photorespiration at high CO2 leads to decreased assimilation of nitrate, which shifts the C/N balance.
PHYSIOLOGIA PLANTARUM
(2022)
Article
Environmental Sciences
Lindsay A. Green-Gavrielidis, Carol S. Thornber
Summary: Global climate change has led to increased sea surface temperatures and altered precipitation patterns worldwide. The study found that high nitrogen enhanced the growth rate of Ulva compressa, while increased temperatures did not have a significant effect on their growth. Nitrogen limitation impacted both species.
ESTUARIES AND COASTS
(2022)
Article
Agriculture, Multidisciplinary
Graeme J. Doole, Alvaro J. Romera, Jennifer E. Leslie, David F. Chapman, Ina (J. B. ) Pinxterhuis, Peter D. Kemp
Summary: The New Zealand Government has focused on regulating nitrogen-leaching losses in pasture-based dairy production. The study suggests that adopting narrow-leaved plantain can reduce nitrogen leaching risk, increase total dairy profit, and boost national economic output.
AGRICULTURAL SYSTEMS
(2021)
Article
Green & Sustainable Science & Technology
Martin Correa-Luna, Daniel Donaghy, Peter Kemp, Laurence Shalloo, Elodie Ruelle, Deirdre Hennessy, Nicolas Lopez-Villalobos
Summary: The study aimed to model and compare the productivity, profitability, and nitrogen utilization efficiency (NUE) of two spring-calving pasture-based milk production systems in New Zealand with different milking frequencies and intensification levels. Results showed that milking frequency, use of feed supplementation, and nitrogen fertilizer application can impact the productivity, profitability, and nitrogen balance of grazing dairy systems. Additionally, the study found that the high-intensity production system had higher profitability per hectare and nitrogen utilization efficiency compared to the low-intensity production system.
Article
Agronomy
Javier Garcia-Favre, Ignacio F. Lopez, Lydia M. Cranston, Daniel J. Donaghy, Peter D. Kemp
Summary: The growth of pasture brome is influenced by defoliation frequency and soil water conditions. Low defoliation frequency and well-watered conditions promote the growth of the grass, enhancing production and survival during drought.
Article
Green & Sustainable Science & Technology
Martin Correa-Luna, Daniel Donaghy, Peter Kemp, Michael Schutz, Nicolas Lopez-Villalobos
Summary: Milk urea nitrogen content is moderately heritable and phenotypically related to urine nitrogen. However, selecting cows for low MUNBV did not effectively reduce nitrogen losses and increase the NUE in two dairy farms of contrasting farming intensity.
Article
Agriculture, Multidisciplinary
Maria J. Rodriguez, Soledad Navarrete, Dave J. Horne, James A. Hanly, Peter Bishop, Peter D. Kemp
Summary: This study investigated the effects of aucubin exuded by plantain roots on nitrogen leaching and nitrous oxide emissions. It was found that aucubin can reduce nitrous oxide emissions through mechanisms in the soil, but does not affect nitrate leaching.
NEW ZEALAND JOURNAL OF AGRICULTURAL RESEARCH
(2023)
Review
Agronomy
Mitchell Andrews, John A. Raven
Summary: This study collates and analyzes data from the literature regarding the effects of genotype and environment on the partitioning of NO3- assimilation between root and shoot of terrestrial vascular plants. The results show that different plant species have different proportions of NO3- assimilation in their roots and shoots under different concentrations of soil NO3-. Factors such as high NH4+ supply, mycorrhizal infection, and parasitic plant infection can increase the proportion of shoot NO3- assimilation, while abiotic stress and elevated atmospheric CO2 can decrease it. Resolving the discrepancies between different studies is an important area for future research.
Article
Agriculture, Dairy & Animal Science
Soledad Navarrete, Maria Rodriguez, David Horne, James Hanly, Mike Hedley, Peter Kemp
Summary: Plantain pasture can reduce nitrogen load in urine, thus reducing nitrogen leaching losses. Research has shown that plantain pasture does not affect milk solids production, and the lower urine nitrogen concentration in summer to autumn helps to reduce nitrogen loss.
Review
Agriculture, Dairy & Animal Science
T. T. Nguyen, Soledad Navarrete, David J. Horne, Danny J. Donaghy, Peter D. Kemp
Summary: Plantain inclusion in grazing pastures significantly increases milk yield, milk solids yield, and milk protein yield, while maintaining milk protein concentration and milk fat yield, but reduces milk fat concentration. Feeding pastures containing plantain reduces urinary nitrogen concentration and total excretion, while increasing daily urine volume.
ANIMAL FEED SCIENCE AND TECHNOLOGY
(2022)
Article
Agronomy
Javier Garcia-Favre, Ignacio F. Lopez, Lydia M. Cranston, Daniel J. Donaghy, Peter D. Kemp, Ivan P. Ordonez
Summary: This study evaluated the performance of Lolium perenne L. and Bromus valdivianus Phil. in terms of production, persistence, and feed quality under different defoliation regimens. The results showed that the mixed planting of the two species had higher production, and Bromus valdivianus performed better during drought periods. The higher root biomass of Bromus valdivianus indicated its adaptation to low soil water availabilities, but low defoliation frequencies during spring may compromise the forage quality. Flexible grazing management can increase the niche utilization between the two species in the mixture.
JOURNAL OF AGRONOMY AND CROP SCIENCE
(2023)
Review
Agronomy
Sarmini Maheswaran, Lydia M. Cranston, James P. Millner, David J. Horne, James A. Hanly, Paul R. Kenyon, Peter D. Kemp
Summary: This article reviews the literature on nitrate leaching under sheep grazing systems, highlighting the importance of urinary nitrogen as a key source. Nitrogen excretion in sheep urine varies greatly in volume, concentration, and frequency, leading to variation in nitrate leaching rates. Further research is needed to quantify nitrate leaching levels under current sheep farming practices and understand the potential impacts on water quality.
Article
Agronomy
Clyton Moyo, Kerry C. Harrington, Peter D. Kemp, Johannes P. J. Eerens, Hossein Ghanizadeh
Summary: Wiper applicators are effective in selectively controlling Cirsium arvense, a troublesome weed in pastures. Double passes with glyphosate, clopyralid, and metsulfuron in a rotary weed wiper achieved significant reductions in stem density. However, damage to pasture plants can occur, particularly if rain follows wiper application. Glyphosate is the best choice for managing C. arvense with wipers, as it causes the least damage if washed off by rain.
Article
Agriculture, Dairy & Animal Science
Thi Truong Nguyen, Soledad Navarrete, David Horne, Daniel Donaghy, Racheal H. Bryant, Peter Kemp
Summary: Incorporating forage plantain into the diet of grazing dairy cows can reduce nitrogen losses from pastoral systems. Increasing plantain proportion in the diet leads to increased urine volume and diluted urine N concentration, which can be beneficial for plant growth. This study found that including 25% plantain in the diet increased urine volume and urination frequency, while reducing urine N% in the morning. Ensuring a minimum of 20% plantain in the diet can help reduce N leaching risk from grazing dairy cows.
Article
Agronomy
Thi Truong Nguyen, Soledad Navarrete, David J. Horne, Daniel J. Donaghy, Peter D. Kemp
Summary: This study evaluated the effects of different sowing rates on the dry matter yield, botanical composition, nutritive value, and bioactive compounds of a pasture mixture of plantain, perennial ryegrass, and white clover. The results showed that incorporating plantain into the pasture improved the nutritive quality and increased the content of various nutrients and bioactive compounds. These effects were linearly associated with the content of plantain leaves in the pasture and were higher in summer and autumn.
Article
Engineering, Civil
Tirupan Mandal, Ali Arabzadeh, Ali Morovatdar, Peter Kemp
Summary: Currently, Wisconsin allows traffic on the cold in-place recycled (CIR) base layer shortly after construction. However, there is no quantitative measure to estimate when it is safe to open the traffic. To overcome this issue, the feasibility of using quantitative and real-time evaluation techniques was investigated. Long-pin shear (LPS) and short-pin raveling (SPR) tests were used to measure the properties of the CIR layer, and regression models were developed using in situ moisture content for proposing threshold values in Wisconsin.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Engineering, Civil
Ali Morovatdar, Tirupan Mandal, Ali Arabzadeh, Peter Kemp
Summary: The traffic speed deflectometer (TSD) is gaining interest for pavement management practices, allowing continuous collection of deflection data at traffic speed without traffic control. However, limited studies have been conducted in cold regions regarding the potential use of TSD data for pavement structural assessment. This study aimed to bridge this gap by developing a twofold approach to characterize pavement integrity and compare TSD and falling weight deflectometer (FWD) data.
TRANSPORTATION RESEARCH RECORD
(2023)