Probing the toxicity of hydrothermal carbonised wastes on soil biota: Effect of reaction temperature and feedstock.

Hydrothermal carbonised wastes (hydrochars) can have toxic effects on soil biota, but factors influencing toxin formation in hydrochar, and subsequent toxicity to soil organisms, have not been elucidated. This study investigated the toxicity of hydrochars on soil biota, with a focus on earthworm (Eisenia fetida) avoidance, microbial metabolic quotient (qCO) and microbial activities. Two reaction temperatures (200 °C and 260 °C) and different feedstocks (biosolids, chicken manure and rice straw) were used.

Accumulation patterns of anthocyanin and γ-oryzanol during black rice grain development.

Pigmented rice, especially black rice, is gaining popularity as it is rich in antioxidants such as anthocyanins and γ-oryzanol. At present, knowledge about temporal control of biosynthesis and accumulation of antioxidants during grain development is limited. To address this, the accumulation patterns of anthocyanins and γ-oryzanol were assessed in two distinct black rice genotypes over the course of grain development, and the expression of known regulatory genes for anthocyanin biosynthesis was examined.

Salinity and nitrogen source affect productivity and nutritional value of edible halophytes.

Saline agriculture may contribute to food production in the face of the declining availability of fresh water and an expanding area of salinized soils worldwide. However, there is currently little known about the biomass and nutrient/antinutrient accumulation response of many edible halophytes to increasing levels of salinity and nitrogen source. To address this, two glass house experiments were carried out.

Fate and recovery of nitrogen applied as slow release brown coal-urea in field microcosms: N tracer study.

The over-use of synthetic nitrogen (N) fertilisers for crop production can cause environmental pollution through leaching and gaseous losses, resulting in low N use efficiency (NUE). Previous work has shown that brown coal (BC) combined with urea can slow down the fertiliser-N release to better synchronise soil N supply with crop N demand. The study aimed to evaluate the impact of granulated BC-urea (BCU) applied to sweet corn on NUE, fate and recovery of fertiliser-N using an N tracer technique.

Effect of Stock Plant Growing Medium and Density upon a Cutting Propagation System for Tea Tree, .

To offer a viable alternative to seedling deployment of tea tree, clones will require the development of an efficient, robust, and vegetative propagation system for the large number of plants needed for plantations (i.e., typically 33,000 plants/ha).

Microspectroscopic visualization of how biochar lifts the soil organic carbon ceiling.

The soil carbon (C) saturation concept suggests an upper limit to the storage of soil organic carbon (SOC). It is set by the mechanisms that protect soil organic matter from mineralization. Biochar has the capacity to protect new C, including rhizodeposits and microbial necromass.

Does Coffee Have Terroir and How Should It Be Assessed?

The terroir of coffee is defined as the unique sensory experience derived from a single origin roasted coffee that embodies its source. Environmental conditions such as temperature, altitude, shade cover, rainfall, and agronomy are considered the major parameters that define coffee terroir. However, many other parameters such as post-harvest processing, roasting, grinding, and brewing can combine to influence the perception of terroir.

Herbicide residues in Australian grain cropping soils at sowing and their relevance to crop growth.

Herbicides are used extensively in Australian grain cropping systems. Despite occasional observations of herbicide-induced phytotoxicity, there is little information on the persistence and carryover of multiple herbicide classes in cropping soils and the risk to subsequent crops. Two soil surveys were conducted, in 2015 (n = 40) and 2016 (n = 42), across different Australian grain cropping fields prior to sowing of winter crops, and soil samples analysed for herbicide residues (16 analytes in 2015 and 22 analytes in 2016).

Winter Wheat ( L.) Tolerance to Mulch.

Mulch from cover crops can effectively suppress weeds in organic corn ( L.) and soybean ( L.) as part of cover crop-based rotational no-till systems, but little is known about the feasibility of using mulch to suppress weeds in organic winter small grain crops.

Remobilization and fate of sulphur in mustard.

Background And Aims: Sulphur (S) is an essential macronutrient involved in numerous metabolic pathways required for plant growth. Crops of the plant family Brassicaceae require more S compared with other crops for optimum growth and yield, with most S ultimately sequestered in the mature seeds as the storage proteins cruciferin and napin, along with the unique S-rich secondary metabolite glucosinolate (GSL). It is well established that S assimilation primarily takes place in the shoots rather than roots, and that sulphate is the major form in which S is transported and stored in plants.

Seed glucosinolate yield is maximized by higher rates of sulfur nutrition than required for seed yield in condiment mustard (Brassica juncea L.).

Brassica crops require high amounts of inorganic sulfur (S) for optimum yield, and are characterized by the synthesis of S-rich glucosinolates (GSL). Although it is well established that seed and GSL yield can be increased by S fertilizer, the detailed relationship between S supply as primary source and the harvestable sinks of seed GSL and storage proteins is poorly understood. We tested the hypothesis that Brassica juncea mustard seed acts as a secondary S sink, and so require a higher rate of S to achieve maximum seed GSL compared to rates required to attain maximum seed biomass.

Pinto peanut cover crop nitrogen contributions and potential to mitigate nitrous oxide emissions in subtropical coffee plantations.

Many coffee (Coffea arabica L) production systems are characterised by high use of nitrogen (N) fertilisers, which can result in N leaching and emissions of nitrous oxide (NO). We investigated the potential for legume cover crops grown inter-row to provide N for coffee trees and lower seasonal NO emissions compared to poultry litter amendment at two subtropical field sites over 12 months, with unfertilised traditional grass groundcover used as a control treatment. Groundcovers (legume and grass treatments) were slashed from the inter-row into the tree line every 2-6 weeks as per normal farming operations.

Transcriptional response of rice flag leaves to restricted external phosphorus supply during grain filling in rice cv. IR64.

Plant phosphorus (P) remobilisation during leaf senescence has fundamental implications for global P cycle fluxes. Hypothesising that genes involved in remobilisation of P from leaves during grain filling would show altered expression in response to P deprivation, we investigated gene expression in rice flag leaves at 8 days after anthesis (DAA) and 16 DAA in plants that received a continuous supply of P in the nutrient solution vs plants where P was omitted from the nutrient solution for 8 consecutive days prior to measurement. The transcriptional response to growth in the absence of P differed between the early stage (8 DAA) and the later stage (16 DAA) of grain filling.

Phosphorus uptake commences at the earliest stages of seedling development in rice.

Seed phosphorus (P) reserves are essential for seedling development; however, we hypothesise that the quantity of P in seeds will lose importance in cultivars that rapidly acquire it via their roots. Our objective in this study was therefore to investigate the onset of seedling P uptake in rice (Oryza sativa). This was addressed through 33P-labelled supply and through measuring P depletion in combination with the detection of P transporter activity in the root tissue of three rice cultivars during early development.

Remobilisation of phosphorus fractions in rice flag leaves during grain filling: Implications for photosynthesis and grain yields.

Phosphorus (P) is translocated from vegetative tissues to developing seeds during senescence in annual crop plants, but the impact of this P mobilisation on photosynthesis and plant performance is poorly understood. This study investigated rice (Oryza sativa L.) flag leaf photosynthesis and P remobilisation in a hydroponic study where P was either supplied until maturity or withdrawn permanently from the nutrient solution at anthesis, 8 days after anthesis (DAA) or 16 DAA.

Analysis of Lysophospholipid Content in Low Phytate Rice Mutants.

As a fundamental component of nucleic acids, phospholipids, and adenosine triphosphate, phosphorus (P) is critical to all life forms, however, the molecular mechanism of P translocation and distribution in rice grains are still not understood. Here, with the use of five different low phytic acid (lpa) rice mutants, the redistribution in the main P-containing compounds in rice grain, phytic acid (PA), lysophospholipid (LPL), and inorganic P (Pi), was investigated. The lpa mutants showed a significant decrease in PA and phytate-phosphorus (PA-P) concentration with a concomitant increase in Pi concentration.

Fire and Brimstone: Molecular Interactions between Sulfur and Glucosinolate Biosynthesis in Model and Crop Brassicaceae.

Glucosinolates (GSLs) represent one of the most widely studied classes of plant secondary metabolite, and have a wide range of biological activities. Their unique properties also affect livestock and human health, and have been harnessed for food and other end-uses. Since GSLs are sulfur (S)-rich there are many lines of evidence suggesting that plant S status plays a key role in determining plant GSL content.

A Belated Green Revolution for Cannabis: Virtual Genetic Resources to Fast-Track Cultivar Development.

Cannabis is a predominantly diecious phenotypically diverse domesticated genus with few if any extant natural populations. International narcotics conventions and associated legislation have constrained the establishment, characterization, and use of Cannabis genetic resource collections. This has resulted in the underutilization of genepool variability in cultivar development and has limited the inclusion of secondary genepools associated with genetic improvement strategies of the Green Revolution.

Phosphorus remobilization from rice flag leaves during grain filling: an RNA-seq study.

The physiology and molecular regulation of phosphorus (P) remobilization from vegetative tissues to grains during grain filling is poorly understood, despite the pivotal role it plays in the global P cycle. To test the hypothesis that a subset of genes involved in the P starvation response are involved in remobilization of P from flag leaves to developing grains, we conducted an RNA-seq analysis of rice flag leaves during the preremobilization phase (6 DAA) and when the leaves were acting as a P source (15 DAA). Several genes that respond to phosphate starvation, including three purple acid phosphatases (OsPAP3, OsPAP9b and OsPAP10a), were significantly up-regulated at 15 DAA, consistent with a role in remobilization of P from flag leaves during grain filling.

From promise to application: root traits for enhanced nutrient capture in rice breeding.

Improving nutrient uptake is an objective in crop breeding, especially in tropical areas where infertile soils dominate and farmers may not have the resources to improve soil fertility through fertilizer application. Scientific endeavors to understand the genetic basis of nutrient acquisition have mostly followed reverse genetic approaches. This has undoubtedly led to improved understanding of basic principles in root development and nutrient transport.

Novel Applications for Oxalate-Phosphate-Amine Metal-Organic-Frameworks (OPA-MOFs): Can an Iron-Based OPA-MOF Be Used as Slow-Release Fertilizer?

A porous iron-based oxalate-phosphate-amine metal-organic framework material (OPA-MOF) was investigated as a microbially-induced slow-release nitrogen (N) and phosphorus (P) fertilizer. Seedling growth, grain yields, nutrient uptake of wheat plants, and soil dynamics in incubated soil, were investigated using OPA-MOF vs standard P (triple-superphosphate) and N (urea) fertilizers in an acidic Ferralsol at two application rates (equivalent 120 and 40 kg N ha(-1)). While urea hydrolysis in the OPA-MOF treatment was rapid, conversion of ammonium to nitrate was significantly inhibited compared to urea treatment.

Unmasking Novel Loci for Internal Phosphorus Utilization Efficiency in Rice Germplasm through Genome-Wide Association Analysis.

Depletion of non-renewable rock phosphate reserves and phosphorus (P) fertilizer price increases has renewed interest in breeding P-efficient varieties. Internal P utilization efficiency (PUE) is of prime interest because there has been no progress to date in breeding for high PUE. We characterized the genotypic variation for PUE present within the rice gene pool by using a hydroponic system that assured equal plant P uptake, followed by mapping of loci controlling PUE via Genome-Wide Association Studies (GWAS).

Genotypic variation in lysophospholipids of milled rice.

Phospholipids (PLs) play a prominent role in both grain cellular structure and nutritional function of cereal crops. Their lyso forms (lysophospholipids, LPLs) often combine with cereal starch to form an amylose-lipid complex (ALC), which may influence starch properties. In this study, 20 rice accessions were grown over two seasons at the same location to explore diversity in LPLs of milled rice.

Determination of starch lysophospholipids in rice using liquid chromatography-mass spectrometry (LC-MS).

Acquiring a complete understanding of rice starch lysophospholipids (LPLs), their biosynthetic pathways and genetic diversity, and the influence of genotype by environment interactions has been hampered by the lack of efficient high-throughput extraction and analysis methods. It was hypothesized a single-step aqueous n-propanol extraction combined with liquid chromatography-mass spectrometry (LC-MS) could be employed to analyze starch LPLs in white rice. The investigation found different grinding methods showed little effect on the final LPL detected, and a simple single-step extraction with 75% n-propanol (8 mL/0.