Alternative fungicides for controlling husk spot caused by Pseudocercospora macadamiae in macadamia

Husk spot, caused by Pseudocercospora macadamiae is a major fungal disease of macadamia in Australia. Chemicals to control the disease are limited and frequent failure to control the disease is a major concern to growers. The overall goal of this research was to improve the chemical control strategy of P. macadamiae through the provision of fungicides with different modes of action to carbendazim, which is the current industry standard. Husk spot incidence, premature fruit abscission, kernel quality and yield were evaluated following application of different fungicide products in replicated field experiments at three different sites. Results showed significant differences in disease incidence and premature fruit abscission between fungicide treatments, field sites and years. Generally, disease incidence and premature fruit abscission on trees treated with fungicide were significantly (P < 0.05) lower than the untreated control. Pyraclostrobin conferred significantly better protection than trifloxystrobin, reducing disease severity by 70% compared with a 50% reduction by trifloxystrobin. The pyraclostrobin treatment had a similar efficacy to the current industry standard (70% reduction cf. 73% reduction by tank-mixed carbendazim and copper). Higher amounts of immature kernels occurred in the untreated control, followed by difenoconazole and trifloxystrobin. Diseased fruit accounted for 78% of premature fruit abscission, which indicates that husk spot enhances fruit abscission in macadamia. Our results suggest that pyraclostrobin provided similar efficacy to the industry standard and could, therefore, play a key role in the management of husk spot.

Genetic Impacts of the Hull on Barley Grain Quality

Barley hull plays an important role in malt and feed quality and processing. In this study we measured the variation in hull con-tent along with other grain quality traits namely, kernel discolouration and degree of pre-harvest sprouting, in a single map-ping population. There were significant (p < 0.05) genetic as well as environment effects. In addition, heritability was calculated for hull content to be 29% and 47% for two years’ data. From the analysis, major QTL markers were identified in con-trolling the expression of hull content on chromosomes 2 (2H), and 6 (6H) with significant (P < 0.05) LOD scores of 5.4 and 3.46 respectively. Minor QTLs were identified on 1 (7H), 4 (4H), 5 (1H) and 7 (5H). The region at marker Bmac310 on 4(4H) could be associated with dormancy gene SD4. A number of the QTLs also coincided with regions for either kernel discolouration or preharvest sprouting resistance (dormancy). The results indicate that variation exists for hull content, which is influenced by both growing environment as well as genetically, although the genetic variance explained less than half of the total variance. Further, hull content also impacts on other grain quality attributes including dormancy, sprouting resistance and kernel appearance.

Measurement of genetic and environmental variation in barley (Hordeum vulgare) grain hardness

In this study, we assessed a broad range of barley breeding lines and commercial varieties by three hardness methods (two particle size methods and one crush resistance method (SKCS—Single-Kernel Characterization System), grown at multiple sites to see if there was variation in barley hardness and if that variation was genetic or environmentally controlled. We also developed near-infrared reflectance (NIR) calibrations for these three hardness methods to ascertain if NIR technology was suitable for rapid screening of breeding lines or specific populations. In addition, we used this data to identify genetic regions that may be associated with hardness. There were significant (p<0.05) genetic effects for the three hardness methods. There were also environmental effects, possibly linked to the effect of protein on hardness, i.e. increasing protein resulted in harder grain. Heritability values were calculated at >85% for all methods. The NIR calibrations, with R2 values of >90%, had Standard Error of Prediction values of 0.90, 72 and 4.0, respectively, for the three hardness methods. These equations were used to predict hardness values of a mapping population which resulted in genetic markers being identified on all chromosomes but chromosomes 2H, 3H, 5H, 6H and 7H had markers with significant LOD scores. The two regions on 5H were on the distal end of both the long and short arms. The region that showed significant LOD score was on the long arm. However, the region on the short arm associated with the hardness (hordoindoline) genes did not have significant LOD scores. The results indicate that barley hardness is influenced by both genotype and environment and that the trait is heritable, which would allow breeders to develop very hard or soft varieties if required. In addition, NIR was shown to be a reliable tool for screening for hardness. While the data set used in this study has a relatively low variation in hardness, the tools developed could be applied to breeding populations that have large variation in barley grain hardness.

Characterization of tree-to-tree variation in morphological, nutritional and medicinal properties of Canarium indicum nuts

As part of a feasibility study of the commercialization potential of C. indicum nuts as Agroforestry Tree Products in Papua New Guinea, preliminary characterization studies have examined the tree-to-tree variation in morphological traits (nut and kernel mass and kernel:nut ratio), as well as nutritional (carbohydrate, fat, protein, sodium, vitamin E) and medicinal traits (anti-oxidant activity, anti-inflammatory activity and phenolic content) of kernels from 18 to 72 trees in a small number of different villages of Papua New Guinea (East New Britain Province). There was continuous variation in these traits indicating opportunities for multiple trait cultivar development targeted at food and pharmaceutical markets. Certain traits, for example anti-inflammatory activity, in which tree-to-tree variation was highly significant, present greater opportunities than others, such as saturated:unsaturated fatty acid ratio. This intraspecific variation was greater within populations than between populations. The data presented has allowed the development of a strategy to domesticate C. indicum for cultivation in homegardens and cocoa-coconut agroforests, using a participatory approach aimed at the production of agroforestry tree products (AFTPs) to empower small-holders and enhance their livelihoods and income.

Country of Origin and Internet Publication: Applying the Berne Convention in the Digital Age

Historically, determining the country of origin of a published work presented few challenges, because works were generally published physically – whether in print or otherwise – in a distinct location or few locations. However, publishing opportunities presented by new technologies mean that we now live in a world of simultaneous publication – works that are first published online are published simultaneously to every country in world in which there is Internet connectivity. While this is certainly advantageous for the dissemination and impact of information and creative works, it creates potential complications under the Berne Convention for the Protection of Literary and Artistic Works (“Berne Convention”), an international intellectual property agreement to which most countries in the world now subscribe. Under the Berne Convention’s national treatment provisions, rights accorded to foreign copyright works may not be subject to any formality, such as registration requirements (although member countries are free to impose formalities in relation to domestic copyright works). In Kernel Records Oy v. Timothy Mosley p/k/a Timbaland, et al. however, the Florida Southern District Court of the United States ruled that first publication of a work on the Internet via an Australian website constituted “simultaneous publication all over the world,” and therefore rendered the work a “United States work” under the definition in section 101 of the U.S. Copyright Act, subjecting the work to registration formality under section 411. This ruling is in sharp contrast with an earlier decision delivered by the Delaware District Court in Håkan Moberg v. 33T LLC, et al. which arrived at an opposite conclusion. The conflicting rulings of the U.S. courts reveal the problems posed by new forms of publishing online and demonstrate a compelling need for further harmonization between the Berne Convention, domestic laws and the practical realities of digital publishing. In this chapter, we argue that even if a work first published online can be considered to be simultaneously published all over the world it does not follow that any country can assert itself as the “country of origin” of the work for the purpose of imposing domestic copyright formalities. More specifically, we argue that the meaning of “United States work” under the U.S. Copyright Act should be interpreted in line with the presumption against extraterritorial application of domestic law to limit its application to only those works with a real and substantial connection to the United States. There are gaps in the Berne Convention’s articulation of “country of origin” which provide scope for judicial interpretation, at a national level, of the most pragmatic way forward in reconciling the goals of the Berne Convention with the practical requirements of domestic law. We believe that the uncertainties arising under the Berne Convention created by new forms of online publishing can be resolved at a national level by the sensible application of principles of statutory interpretation by the courts. While at the international level we may need a clearer consensus on what amounts to “simultaneous publication” in the digital age, state practice may mean that we do not yet need to explore textual changes to the Berne Convention.

Spectral analysis of pair-correlation bandwidth: Application to cell biology images

Images from cell biology experiments often indicate the presence of cell clustering, which can provide insight into the mechanisms driving the collective cell behaviour. Pair-correlation functions provide quantitative information about the presence, or absence, of clustering in a spatial distribution of cells. This is because the pair-correlation function describes the ratio of the abundance of pairs of cells, separated by a particular distance, relative to a randomly distributed reference population. Pair-correlation functions are often presented as a kernel density estimate where the frequency of pairs of objects are grouped using a particular bandwidth (or bin width), Δ>0. The choice of bandwidth has a dramatic impact: choosing Δ too large produces a pair-correlation function that contains insufficient information, whereas choosing Δ too small produces a pair-correlation signal dominated by fluctuations. Presently, there is little guidance available regarding how to make an objective choice of Δ. We present a new technique to choose Δ by analysing the power spectrum of the discrete Fourier transform of the pair-correlation function. Using synthetic simulation data, we confirm that our approach allows us to objectively choose Δ such that the appropriately binned pair-correlation function captures known features in uniform and clustered synthetic images. We also apply our technique to images from two different cell biology assays. The first assay corresponds to an approximately uniform distribution of cells, while the second assay involves a time series of images of a cell population which forms aggregates over time. The appropriately binned pair-correlation function allows us to make quantitative inferences about the average aggregate size, as well as quantifying how the average aggregate size changes with time.

Barley Grains Defects (Blackpoint, Pre-harvest sprouting, Kernal staining)

Screening new and existing breeding germplasm and cultivars for grain defect tolerance for breeding programs, evaluate new methods and technologies to screen more effectively for the barley grains defects - pre-harvest sprouting, blackpoint, kernel discolouration, and investigate genetic mechanisms involved in controlling barley grain defect tolerance.

National screening for barley grain defects

Three defects on barley grain can impact on the price paid to grain growers. Black point (BP), kernel staining (KS) and pre-harvest sprouting (PHS) can result in malting barley being downgraded to feed. Resistance to these defects is the best option, and in this project hundreds of breeding lines grown over three years were screened for these traits. A number of lines exhibited resistance to each defect but very few had resistance to all defects. The results from the screening program have been provided to the Australian barley breeders through the Barley Breeding Australia (BBA) program.

Genetic and Malt Quality Diversity of East Asian Two-Rowed Barley Accessions in Relationship to North American Malting Barley.

Because of epidemics of Fusarium head blight (FHB; caused by Fusarium graminearum Schwabe [teleomorph Gibberella zeae (Schwein.) Petch]) in the northern Great Plains of the United States and Canada in the past two decades, malting barley breeders have been forced to use nonadapted barley (Hordeum vulgare L.) accessions as sources of FHB resistance. Many of the resistant accessions are from East Asia, and limited information is available on their genetic diversity and malt quality. The objectives of this study were to determine the genetic diversity among 30 East Asian accessions and two North American cultivars. Genetic diversity was based on 49 simple-sequence repeat markers. All accessions were tested for barley grain brightness; protein content; 1,000-kernel weight; malting loss; fine-grind malt extract; content of plump kernels, free amino nitrogen, soluble protein, and wort beta-glucan; the Kolbach index (i.e., the ratio of malt soluble protein to malt total protein); a-amylase activity; diastatic power; won color; and wort viscosity. A few accessions had equal quality compared with Harrington and Conlon barley for individual traits but not for all. Qing 2, Mokkei 93-78, and Nitakia 48 could be excellent sources for increased malt extract; Nitakia 48 is a possible source for low wort viscosity; and Mokkei 93-78 and Nitakia 48 are putative sources of low beta-glucan content. The cluster analyses also implied that the malt quality of an accession cannot be predicted based on the country where it was developed.

Genetic effects and genetic relationships among shrunken (sh2) sweet corn lines and F1 hybrids

The objectives of this study were to quantify the components of genetic variance and the genetic effects, and to examine the genetic relationship of inbred lines extracted from various shrunken2(sh2) breeding populations. Ten diverse inbred lines developed from genetic background, were crossed in half diallel. Parents and their F1 hybrids were evaluated at three environments. The parents were genotyped using 20 polymorphic simple sequence repeats (SSR). Agronomic and quality traits were analysed by a mixed linear model according to additive-dominance genetic model. Genetic effects were estimated using an adjusted unbiased prediction method. Additive variance was more important than dominance variance in the expression of traits related to ear aspects (husk ratio and percentage of ear filled) and eating quality (flavour and total soluble solids). For agronomic traits, however, dominance variance was more important than additive variance. The additive genetic correlation between flavour and tenderness was strong (r = 0.84, P <0.01). Flavour, tenderness and kernel colour additive genetic effects were not correlated with yield related traits. Genetic distance (GD), estimated from SSR profiles on the basis of Jaccard's similarity coefficient varied from 0.10 to 0.77 with an average of 0.56. Cluster analysis classified parents according to their pedigree relationships. In most studied traits, F1 performance was not associated with GD.

Northern challanges for profitable production of quality naked oat

Naked oat (Avena sativa f.sp. nuda L.) is the highest quality cereal in northern growing conditions. However the cultivation area of naked oat is remarkably small. Major challenges for naked oat production are to observe its nakedness. The caryopsis of naked oat is sensitive to mechanical damage at harvest, especially at high grain moisture content. The greater the grain moisture content of naked oat at harvest, the more loses of germination capacity was caused by threshing. For producing high quality naked oat seed, it is recommended that harvesting be done at as low grain moisture content as possible. However, if this is not possible, better germination can be ensure with gentle harvest by reducing the cylinder speed. In spite of conventional oat s excellent fat and amino acid composition in animal feed use, as far as nutritional value is concerned, the total energy yield of oat is weaker than other cereals because of the hulls. Also with naked oat the dehulling is not complete, while hull content on different cultivars mostly varied between one to six percent. In addition to genotype, environmental conditions markedly control the expression of nakedness. Thresher settings had only limited effects on hull content. The function of hulls is to protect the groat, but this was confirmed only for Finnish, small grain, cultivar Lisbeth. The oat kernel is generally covered with fine silky hairs termed trichomes. The trichomes of naked oat are partly lost during threshing and handling of grains. Trichomes can cause itchiness in those handling the grains and also accumulate and form fine dust and can block-up machinery. The cultivars differed considerably in pubescence. Some thresher settings, including increased cylinder speed, slightly increased grain polishing such that grains had some areas completely free of trichomes. Adjusting thresher settings was generally not an efficient means of solving the problems associated with naked oat trichomes. The main differences in cultivation costs between naked and conventional oat lie in the amount of seeds required and the drying costs. The main differences affecting the economic result lie in market prices, yield level and feed value. The results indicate that naked oat is financially more profitable than conventional oat, when the crop is sold at a specific price at all yield levels and when the crop is used as feed at highest yield level. At lower yield levels, conventional oat is, in spite of its lower feed value, the more profitable option for feed use. Dehulled oat did not achieve the same economic result as naked oat, as the cost of dehulling, including the hull waste, was considerable. According to this study naked oat can be cultivated successfully under northern conditions, when taking into consideration the soft, naked grain through cultivation chain.

Occurrence and properties of steryl ferulates and glycosides in wheat and rye

Cereal kernels are known to contain a number of minor components that possess beneficial health attributes. In this thesis rye and wheat were studied as sources of steryl ferulates and steryl glycosides and their behaviour in processing were evaluated. Further, enzymatic hydrolysis of these conjugates was studied, as well as the capacity of steryl ferulates to inhibit lipid oxidation at different temperatures. Steryl ferulates were shown to have a strong positive correlation with dietary fibre contents in milling fractions from the outer parts of the kernels obtained from a commercial scale mill. Highest contents of steryl ferulates were found in the bran in both cereals, with the content decreasing once moving towards the inner parts of the kernel. Variation in the contents of steryl ferulates was higher in wheat fractions than rye fractions. Steryl glycosides, on the other hand, had either negative or no correlation with dietary fibre, and the range of the steryl glycoside contents was much narrower than that of steryl ferulates in both cereals. There were significant differences in the sterol compositions of these steryl conjugates when compared with each other or with the total plant sterols in the corresponding fractions. Properties of steryl ferulates and steryl glycosides were evaluated after common processing methods and in enzymatic hydrolysis. Thermal and mechanical processing had only minor or no effects on the contents of steryl conjugates from rye and wheat bran. Enzymatic treatments on the other hand caused some changes, especially in the contents of glycosylated sterols. When steryl ferulates extracted from rye or wheat bran were subjected to enzymatic treatments by steryl esterase, significant differences in the rates of hydrolysis were observed between steryl ferulates from different sources with differing sterol compositions. Further, differences were also observed between enzymes from different sources. Steryl glycosides were shown to be hydrolysed by β-glucosidase (cellobiase) from A. niger, but less with β-glucosidases from other sources. Steryl ferulates showed good antioxidant activity at both moderate and high temperatures. In bulk and emulsion systems of methyl linoleate at 40°C steryl ferulates extracted from rye and wheat bran inhibited hydroperoxide formation much more effectively than synthetic steryl ferulates or those extracted from rice (γ-oryzanol), demonstrating that the sterol composition has an effect on the activity. At cooking (100°C) and frying temperatures (180°C) sitostanyl ferulate was shown to inhibit polymer formation significantly and, especially at 100°C, comparably to α-tocopherol. The rate of antioxidant degradation was slower for sitostanyl ferulate, showing higher heat stability than α-tocopherol. When evaluated as a mixture, no synergistic effect was observed between these two antioxidants. The data presented in this thesis provides information that may henceforth be applied when evaluating the intakes of steryl conjugates from cereal sources, as well as their possible influences as minor bioactive components. Wheat and rye both are good sources of steryl ferulates and steryl glycosides and, especially with steryl ferulates, what may be lost out to some other cereals on quantity is compensated with quality of the sterol composition.

Maintaining high moisture content of macadamia nuts-in-shell during storage induces brown centres in raw kernels

BACKGROUND Kernel brown centres in macadamia are a defect causing internal discolouration of kernels. This study investigates the effect on the incidence of brown centres in raw kernel after maintaining high moisture content in macadamia nuts-in-shell stored at temperatures of 30°C, 35°C, 40°C and 45°C. RESULTS Brown centres of raw kernel increased with nuts-in-shell storage time and temperature when high moisture content was maintained by sealing in polyethylene bags. Almost all kernels developed the defect when kept at high moisture content for 5 days at 45°C, and 44% developed brown centres after only 2 days of storage at high moisture content at 45°C. This contrasted with only 0.76% when stored for 2 days at 45°C but allowed to dry in open-mesh bags. At storage temperatures below 45°C, there were fewer brown centres, but there were still significant differences between those stored at high moisture content and those allowed to dry (P < 0.05). CONCLUSION Maintenance of high moisture content during macadamia nuts-in-shell storage increases the incidence of brown centres in raw kernels and the defect increases with time and temperature. On-farm nuts-in-shell drying and storage practices should rapidly remove moisture to reduce losses. Ideally, nuts-in-shell should not be stored at high moisture content on-farm at temperatures over 30°C. © 2013 Society of Chemical Industry

Nonparametric traversability estimation in partially occluded and deformable terrain

Terrain traversability estimation is a fundamental requirement to ensure the safety of autonomous planetary rovers and their ability to conduct long-term missions. This paper addresses two fundamental challenges for terrain traversability estimation techniques. First, representations of terrain data, which are typically built by the rover’s onboard exteroceptive sensors, are often incomplete due to occlusions and sensor limitations. Second, during terrain traversal, the rover-terrain interaction can cause terrain deformation, which may significantly alter the difficulty of traversal. We propose a novel approach built on Gaussian process (GP) regression to learn, and consequently to predict, the rover’s attitude and chassis configuration on unstructured terrain using terrain geometry information only. First, given incomplete terrain data, we make an initial prediction under the assumption that the terrain is rigid, using a learnt kernel function. Then, we refine this initial estimate to account for the effects of potential terrain deformation, using a near-to-far learning approach based on multitask GP regression. We present an extensive experimental validation of the proposed approach on terrain that is mostly rocky and whose geometry changes as a result of loads from rover traversals. This demonstrates the ability of the proposed approach to accurately predict the rover’s attitude and configuration in partially occluded and deformable terrain.

Sweetcorn colour change and consumer perception associated with increasing zeaxanthin for the amelioration of age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world. Increasing dietary intake of lutein- and zeaxanthin-rich foods is a potential means of preventing, or at least slowing the progression of AMD. Zeaxanthin levels in tropical super-sweetcorn was increased from 1.1 to 11.9 µg/g FW through conventional breeding and selection, associated with both an increase in the proportion of zeaxanthin relative to other carotenoids, and a general increase in carotenoid synthesis. Increasing zeaxanthin was associated with a colour shift from traditional ‘canary-yellow’ kernels to a golden-orange colour. Kernel colour was most closely correlated (r2=69%) with an increase in beta-arm carotenoid concentration. Consumer analysis revealed that prior to any knowledge of zeaxanthin-related health benefit, consumers would readily purchase both yellow and gold cobs. Once the health benefit was explained, this extended to deep-gold cobs. Colour difference between regular yellow sweetcorn and high-zeaxanthin sweetcorn could potentially be used as a visual means of differentiating high-zeaxanthin sweetcorn in the marketplace.