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Intercropping using mixtures of dryland crop species for grain or seed production was investigated in southern Australia across a range of rainfall zones over three years. The objective was to understand the productivity and profitability of intercropping in extensive, high-input grain cropping systems. Previous research has shown large productivity benefits of mixtures; however, few farmers practice intercropping in Australia, and an analysis of profitability is needed to support future potential adoption. Experimental results showed strong mixture responses (in terms of yield, value and land equivalence), but not all were profitable compared to an equivalent share of monoculture crops (as measured by gross margins). The most promising mixtures were those containing high-value crops (canola) and legumes (field pea or faba bean) at the wetter sites where the additional gross margin over equivalent monoculture crops ranged from $12/ha to $576/ha. Mixtures containing highly competitive crops (wheat or barley) were generally unprofitable. Mixtures involving cereals were doubly disadvantaged by the aggressiveness of these lower-value crops in the mixtures we examined and the high grain separation costs post-harvest. Cost reduction in mixture systems involving high-value crops that are synergistic (grain legumes) should provide enduring opportunities for intercropping in southern Australia. [ABSTRACT FROM AUTHOR]

Storing lentil is a strategy used by growers to manage price volatility. However, studies investigating the impact of storage conditions on the market and end use properties of lentil are limited. This study examined the effects of storage temperature (4, 15, 25, and 35 °C) and grain moisture (10 and 14%, w/w) on traits related to market (seed coat colour), viability (germination capacity), and end use properties (hydration capacity, milling efficiency, and cooking quality) in four red lentil cultivars (PBA Bolt, PBA Hallmark, PBA Hurricane, PBA Jumbo2) over 360 days. Storing lentil at 14% moisture content and 35 °C significantly (p = 0.05) darkened seed coat after 30 days, caused complete loss of viability within 180 days and reduced cooking quality (cooked firmness) after 120 days across all tested cultivars. Storing lentil at 10% moisture content and 35 °C reduced hydration capacity after 30 days, and milling efficiency after 120 days across all cultivars tested. PBA Jumbo2 exhibited a higher rate of degradation in hydration capacity and cooking quality, and a lower rate of degradation in the other traits studied. Storing lentil at ≤15 °C prevented degradation of all quality traits. These findings will support improved lentil storage protocols to maintain quality and improve economic outcomes for the pulse industry. [ABSTRACT FROM AUTHOR]

Lentil seed coat colour influences market value, whilst germination is associated with crop establishment and hydration capacity with optimal processing outcomes. Storing lentil grain assists growers in managing price fluctuations; however, exposure to oxygen at higher temperatures during extended storage degrades seed coat colour, germination, and hydration capacity. Depleting oxygen prevents such degradation in other crops; however, studies in lentil are limited. This study examined the effects of oxygen-depleted modified atmospheres and temperatures on seed coat colour, germination, and hydration capacity in two red lentil cultivars, PBA Hallmark and PBA Jumbo2, stored for 360 days. Small volumes of lentil grain were placed in aluminium laminated bags filled with nitrogen (N2), carbon dioxide (CO2), or air and stored at either 15 or 35 °C. At 35 °C in an air atmosphere, the lentil's seed coat significantly (p = 0.05) darkened after 30 days of storage, whereas germination and hydration capacities decreased after 60 days regardless of cultivar. In contrast, N2 and CO2 atmospheres maintained initial seed coat colour, germination, and hydration capacities in both cultivars throughout the study period regardless of temperature. Storing lentil grain in an oxygen-depleted modified atmosphere may assist to maximise returns to grower and maintain key quality traits. [ABSTRACT FROM AUTHOR]

Grains intended for human consumption or feedstock are typically high-value commodities that are marketed based on either their visual characteristics or compositional properties. The combination of visual traits, chemical composition and contaminants is generally referred to as grain quality. Currently, the market value of grain is quantified at the point of receival, using trading standards defined in terms of visual criteria of the bulk grain and chemical constituency. The risk for the grower is that grain prices can fluctuate throughout the year depending on world production, quality variation and market needs. The assessment of grain quality and market value on-farm, rather than post-farm gate, may identify high- and low-quality grain and inform a fair price for growers. The economic benefits include delivering grain that meets specifications maximizing the aggregate price, increasing traceability across the supply chain from grower to consumer and identifying greater suitability of differentiated products for high-value niche markets, such as high protein product ideal for plant-based proteins. This review focuses on developments that quantify grain quality with a range of spectral sensors in an on-farm setting. If the application of sensor technologies were expanded and adopted on-farm, growers could identify the impact and manage the harvesting operation to meet a range of quality targets and provide an economic advantage to the farming enterprise. [ABSTRACT FROM AUTHOR]

The biochemistry underlying seed coat darkening of lentil due to extended storage is limited. This study investigated the relationship between seed coat darkening over time during storage and changes in concentration of phenolic compounds (total phenolic compounds, total condensed tannins, proanthocyanidins and anthocyanins) in two red lentil cultivars (PBA Hallmark and PBA Jumbo2), stored at two grain moisture contents (10 and 14%, w/w) and two temperatures (4 and 35 °C) for 360 days. Seed coat darkening was only significant (p = 0.05) at high temperatures (35 °C) but not at low temperatures (4 °C), irrespective of grain moisture content and cultivar. The concentration of all phenolic compounds tested in this study reduced significantly (p = 0.05) throughout the study period, regardless of temperature and grain moisture treatments. The changes in seed coat brightness and redness followed a linear pattern, except for yellowness, where phenolic compounds initially reduced linearly and then remained constant thereafter. Darkening of seedcoat was only associated with the reduction in phenolic compounds tested in this study at 35 °C, and not at 4 °C. This suggests that seed coat darkening due to extended storage may not be directly linked to broad reductions in the groups of phenolic compounds or individual compounds assessed in this study. This information prompts further research to identify the actual biochemical processes that cause the darkening of seed coats during storage and assist in developing cultivars with stable seed coat colour by selecting and modifying such processes. [ABSTRACT FROM AUTHOR]

This study presents an explanatory biophysical model developed and validated to simulate seed coat colour traits including CIE L*, a*, and b* changes over time for stored lentil cultivars PBA Hallmark, PBA Hurricane, PBA Bolt, and PBA Jumbo2 under diverse storage conditions. The model showed robust performance for all cultivars, with R2 values ≥ 0.89 and RMSE values ≤ 0.0019 for all seed coat colour traits. Laboratory validation at 35 °C demonstrated a high agreement (Lin's Concordance Correlation Coefficient, CCC ≥ 0.82) between simulated and observed values of all colour traits for PBA Jumbo2 and strong agreement (CCC ≥ 0.81) for PBA Hallmark in brightness (CIE L*) and redness (CIE a*), but not in yellowness (CIE b*). At 15 °C, both cultivars exhibited moderate to weak agreement between simulated and observed values of all colour traits (CCC ≤ 0.47), as very little change was recorded in the observed values over the 360 days of storage. Bulk storage system validation for PBA Hallmark showed moderate performance (CCC ≥ 0.46) between simulated and observed values of all colour traits. Modelling to simulate changes in seed coat colour traits of lentils over time will equip growers and traders to make informed managerial decisions when storing lentils for long periods. [ABSTRACT FROM AUTHOR]

In semi‐arid cropping regions where rainfall is variable, stored soil water is important for reducing the impacts of dry periods; however, in‐season evaporation limits yield potential. We tested the productivity benefits of protecting wheat and lentil crops from evaporation using inter‐row polymer cover, when grown in southern Australia. For wheat, white polyvinyl chloride (PVCw) increased yield by 50% (561 kg/ha) and 11% (408 kg/ha) for decile 2 (2018) and 3 (2019) seasonal rainfall respectively; and for lentil, yield increases were 20% (443 kg/ha) in 2019. A sprayable alginate polymer increased wheat yield by 8% (310 kg/ha). Total water use for wheat in 2018 was reduced (17 mm) for PVCw and water use efficiency (WUE) significantly increased from 7 to 11 kg/ha/mm, whereas in 2019, WU was greater (47 mm) for PVCw, but WUE was equivalent to the control (~15 kg/ha/mm). Colour of the PVC modified the light available to the crop and canopy temperature, where a highly reflective inter‐row cover (albedo 0.44) increased wheat yield (~487 kg/ha). For the future, formulations of highly reflective polymers applied in‐season within dryland cropping enterprises are likely to provide production advantages, although logistical viability of application and potential environmental implications may define impediments to adoption. [ABSTRACT FROM AUTHOR]

Frost damage causes significant production losses and costs to Australian dryland wheat, and frost impacts are not expected to decline in the near future, despite global warming. Rapid estimation of frost damage to crops on a spatial basis would allow for timely management decisions to reduce the economic impact of frost events. In this paper, we take a first step in evaluating the utility of hyperspectral reflectance and active light fluorescence for detecting frost damage to wheat during its reproductive phase. Two experiments were conducted immediately after the first observation of frost damage, (i) in 2006, five plots in an existing trial were opportunistically subdivided to take spectral reflectance measurements on frost damaged plants along with yield measurements, and (ii) in 2015, a transect across 31 rows within a commercial paddock was established to evaluate spectral reflectance, fluorometer measurements, and yield along a gradient from non-frosted to frost damaged plants. The results of the hyperspectral reflectance data appeared variable in response across the two experimental sites where frost was observed in-crop. In 2006, hyperspectral-derived indices showed significant differences (P < 0.05) between measurements of frosted and non-frosted canopies, but this was not the case for observations taken in 2015, where the mean response was reversed between experimental sites for several of the indices. In contrast, fluorometer measurements in the 2015 trial resulted in higher correlations with yield and observed frost damage compared with the reflectance measurements. Seven of the nine fluorometer indices evaluated were correlated with yield (used as an indicator of frost damage) at P < 0.01. An index of compounds which absorbs at 375 nm, FLAV, had the best correlation coefficients of 0.91 and 0.90 for the two dates in 2015. The fluorescence indexFLAVwas selected to evaluate whether it could be used to classify the canopy as frost affected or not, using discriminant analysis for the 2015 transect data. The overall classification accuracy, defined as the number of correctly classified measurements (57) divided by the total number (62) was 92%. The present study was not able to provide insight into how rapidly the sensors could detect frost damage before detection with the naked eye, as the survey data constituted a transect based on early visual symptoms, however this study does provide important insight into what sensors and/or indices may be sensitive to 'seeing' early frost damage in-crop. The next steps, which build on this work and need to be resolved are (i) what is the nominal scale of measurements required, and for which portions of the plant canopy? (ii) How robust (over space and time) are any relationships between frost damage and index response? (iii) Can frost damage be detected before the onset of visual damage? [ABSTRACT FROM AUTHOR]

Frost can significantly reduce production of field crops grown in Mediterranean‐type environments, where significant economic losses for Australian wheat occur annually. If non‐destructive sensors could make rapid, spatial assessment of frost damage, this could limit economic losses through timely management decisions. This paper reports on a methodology for imposing frost treatments to wheat under field conditions and the utility of canopy reflectance data for detecting early crop damage. Purpose‐built chambers using stepped additions of dry ice allowed for a range of frost scenarios to be tested when applied at wheat heading and anthesis. For frost treatments applied at anthesis, grain number and yield were reduced by 8.8% and 7.2%, respectively, for every degree Celsius below zero (down to −4°C). This effect was additive over two consecutive nights. For cold load equivalent, there was a 2.2% and 1.9% reduction in grain number and yield, respectively, per °C hr (below 0°C). For wheat, spectral indices PRI and NDVI (reflectance) and FRF_G and SFR_G (fluorescence) showed significant relationships, with cold load applied for heading treatments. Next steps include targeting frost intensities equivalent to cold loads between 20 and 80°C hr and testing the utility of these proposed indices in a commercial paddock setting. [ABSTRACT FROM AUTHOR]

There has been recent interest indesigning smart diagnostic ortherapeutic self-assembling peptide or polymeric materials that canselectively undergo morphological transitions to accumulate at a diseasesite in response to specific stimuli. Developing approaches to probethese self-assembly transitions in environments that accurately amalgamatethe diverse plethora of proteins, biomolecules, and salts of bloodis essential for creating systems that function in vivo. Here, we have developed a fluorescence anisotropy approach to probethe pH-dependent self-assembly transition of peptide amphiphile (PA)molecules that transform from spherical micelles at pH 7.4 to nanofibersunder more acidic pH’s in blood serum. By mixing small concentrationsof a Ru(bipy)32+-tagged PA with a Gd(DO3A)-taggedPA having the same lipid–peptide sequence, we showed that thepH dependence of self-assembly is minimally affected and can be monitoredin mouse blood serum. These PA vehicles can be designed to transitionfrom spherical micelles to nanofibers in the pH range 7.0–7.4in pure serum. In contrast to the typical notion of serum albuminabsorbing isolated surfactant molecules and disrupting self-assembly,our experiments showed that albumin does not bind these anionic PAsand instead promotes nanofibers due to a molecular crowding effect.Finally, we created a medium that replicates the transition pH inserum to within 0.08 pH units and allows probing self-assembly behaviorusing conventional spectroscopic techniques without conflicting proteinsignals, thus simplifying the development pathway from test tube to in vivoexperimentation for stimuli-responsive materials. [ABSTRACT FROM AUTHOR]