Breeding Ananas for the cut-flower and garden markets

Only small quantities of Ananas have been marketed as cut flowers or as potted plants for garden use in Australia. Worldwide there have, until very recent times, been no breeding programs to develop ornamental characteristics and hence the choice of cultivars has been limited mainly to semi-domesticated selections or those developed by amateur enthusiasts. Interest in developing Ananas selections specifically for the ornamental market is now increasing. A small program has operated in Australia since 1995. In this program, a total of 4,700 seedlings were generated over three generations using various parental combinations of Ananas comosus var. comosus, A. comosus var. bracteatus, A. comosus var. ananassoides 'FRF223', A. comosus var. erectifolious 'Selvagem 6' and Ananas macrodontes 'I.26-803'. Several selections have been developed for the garden and or cut-flower market. Characteristics represented include a pink or red syncarp, dark red-brown foliage and a dwarf, clumping growth habit. While a surprising display of ornamental diversity exists within Ananas, the genus is limited in comparison to the other bromeliad genera. Opportunity might exist however to introgress characteristics such as additional foliage colours, plant morphology and syncarp colours from other genera into Ananas.

Landscape structure influences tree density patterns in fragmented woodlands in semi-arid eastern Australia.

Landscape and local-scale influences are important drivers of plant community structure. However, their relative contribution and the degree to which they interact remain unclear. We quantified the extent to which landscape structure, within-patch habitat and their confounding effects determine post-clearing tree densities and composition in agricultural landscapes in eastern subtropical Australia. Landscape structure (incorporating habitat fragmentation and loss) and within-patch (site) features were quantified for 60 remnant patches of Eucalyptus populnea (Myrtaceae) woodland. Tree density and species for three ecological maturity classes (regeneration, early maturity, late maturity) and local site features were assessed in one 100 × 10 m plot per patch. All but one landscape characteristic was determined within a 1.3-km radius of plots; Euclidean nearest neighbour distance was measured inside a 5-km radius. Variation in tree density and composition for each maturity class was partitioned into independent landscape, independent site and joint effects of landscape and site features using redundancy analysis. Independent site effects explained more variation in regeneration density and composition than pure landscape effects; significant predictors were the proportion of early and late maturity trees at a site, rainfall and the associated interaction. Conversely, landscape structure explained greater variation in early and late maturity tree density and composition than site predictors. Area of remnant native vegetation within a landscape and patch characteristics (area, shape, edge contrast) were significant predictors of early maturity tree density. However, 31% of the explained variation in early mature tree differences represented confounding influences of landscape and local variables. We suggest that within-patch characteristics are important in influencing semi-arid woodland tree regeneration. However, independent and confounding effects of landscape structure resulting from previous vegetation clearing may have exerted a greater historical influence on older cohorts and should be accounted for when examining woodland dynamics across a broader range of environments.

"On-the-go" NIT technology to assess protein and moisture during harvest of wheat breeding trials.

In this study, we investigated the application of “on-the-go” assessment of wheat protein and moisture under a breeding trial situation.

Reproduction of family tree, possibly the Gottschalk Stammbaum from the home of Henriette Gottschalk nee Rothschild Genealogy

Others remember the Gottschalk Stammbaum from the home of Henriette Gottschalk nee Rothschild as having only one tree

Taxonomy, distribution and ecology of Zoysia macrantha desv., an Australian native species with turf breeding potential

Only three of the 11 species in the genus Zoysia Willd. have thus far contributed to commercially available turfgrass varieties. One of the neglected taxa is Z. macrantha Desv., an Australian native species further divided into two subspecies. The coarser Z. macrantha subsp. macrantha occurs on sand dunes, headlands and tidal areas along eastern and southeastern coasts from about 23 to 38°S latitude. The shorter, denser-growing Z. macrantha subsp. walshii M.E. Nightingale is found on the southern mainland (South Australia and Victoria from longitude 137° to 148°E and at latitudes higher than 36°S), adjacent offshore islands, and northern, eastern and central Tasmania to 43°S growing on the edges of coastal, sub-coastal and even inland salt lakes, in riverine environments, and from moist grassy depressions (both coastal and inland) to rocky headlands. The latter subspecies has the more discontinuous and specialised distribution, largely determined by the need for an appropriate level of peat, clay or silt in the soil to maintain adequate moisture during the dry summers in southern Australia while at the same time avoiding anything more than temporary waterlogging. It grows on low fertility soils ranging from strongly acid to neutral or mildly alkaline, and is often very closely grazed by marsupials. Both subspecies are salt and drought tolerant, but not notably shade tolerant. Their potential to add greater drought tolerance in particular to the Asian Zoysia material in current use through future breeding programs is discussed.

Comparative performance of Corymbia hybrids and parental species in subtropical Queensland and implications for breeding and deployment.

Eighty six full-sib Corymbia F1 hybrid families (crosses between C. torelliana and four spotted gum taxa: C. citriodora subsp. variegata, C. citriodora subsp. citriodora, C. henryi and C. maculata), were planted in six trials across six disparate sites in south-eastern Queensland to evaluate their productivity and determine their potential utility for plantation forestry. In each trial, the best-growing 20% of hybrid families grew significantly faster (P=0.05) than open-pollinated seedlots of the parent species Corymbia citriodora subsp. variegata, ranging from 107% to 181% and 127% to 287% of the height and diameter respectively. Relative performance of hybrid families growing on more than one site displayed consistency in ranking for growth across sites and analysis showed low genotype-by-environment interaction. Heritability estimates based on female and male parents across two sites at age six years for height and diameter at breast height, were high (0.62±0.28 to 0.64±0.35 and 0.31±0.21 to 0.69±0.37 respectively), and low to moderate (0.03±0.04 to 0.33±0.22) for stem straightness, branch size, incidence of ramicorns, and frost and disease resistance traits at ages one to three years. The proportion of dominance variance for height and diameter had reduced to zero by age six years. Based on these promising results, further breeding and pilot-scale family forestry and clonal forestry deployment is being undertaken. These results have also provided insights regarding the choice of a future hybrid breeding strategy.

Tree growth relationships and silvicultural tools to assist stand management in private native spotted gum dominant forests in Queensland and northern New South Wales.

Spotted gum dominant forests occur from Cooktown in northern Queensland (Qld) to Orbost in Victoria (Boland et al. 2006) and these forests are commercially very important with spotted gum the most commonly harvested hardwood timber in Qld and one of the most important in New South Wales (NSW). Spotted gum has a wide range of end uses from solid wood products through to power transmission poles and generally has excellent sawing and timber qualities (Hopewell 2004). The private native forest resource in southern Qld and northern NSW is a critical component of the hardwood timber industry (Anon 2005, Timber Qld 2006) and currently half or more of the native forest timber resource harvested in northern NSW and Qld is sourced from private land. However, in many cases productivity on private lands is well below what could be achieved with appropriate silvicultural management. This project provides silvicultural management tools to assist extension staff, land owners and managers in the south east Qld and north eastern NSW regions. The intent was that this would lead to improvement of the productivity of the private estate through implementation of appropriate management. The other intention of this project was to implement a number of silvicultural experiments and demonstration sites to provide data on growth rates of managed and unmanaged forests so that landholders can make informed decisions on the future management of their forests. To assist forest managers and improve the ability to predict forest productivity in the private resource, the project has developed: • A set of spotted gum specific silvicultural guidelines for timber production on private land that cover both silvicultural treatment and harvesting. The guidelines were developed for extension officers and property owners. • A simple decision support tool, referred to as the spotted gum productivity assessment tool (SPAT), that allows an estimation of: 1. Tree growth productivity on specific sites. Estimation is based on the analysis of site and growth data collected from a large number of yield and experimental plots on Crown land across a wide range of spotted gum forest types. Growth algorithms were developed using tree growth and site data and the algorithms were used to formulate basic economic predictors. 2. Pasture development under a range of tree stockings and the expected livestock carrying capacity at nominated tree stockings for a particular area. 3. Above-ground tree biomass and carbon stored in trees. •A series of experiments in spotted gum forests on private lands across the study area to quantify growth and to provide measures of the effect of silvicultural thinning and different agro-forestry regimes. The adoption and use of these tools by farm forestry extension officers and private land holders in both field operations and in training exercises will, over time, improve the commercial management of spotted gum forests for both timber and grazing. Future measurement of the experimental sites at ages five, 10 and 15 years will provide longer term data on the effects of various stocking rates and thinning regimes and facilitate modification and improvement of these silvicultural prescriptions.

Productivity of plantation hardwood tree species in north-eastern Australia: A report from the Forest Adaptation and Sequestration Alliance

The report summarises data from a large number of trials of species with potential for use by the plantation forest industry in north-eastern Australia and provides information aimed at improving the understanding of growth rates, pest and disease risks and carbon sequestration. Data is summarised and presented at a regional level as opposed to individual trial or plot level. As well, nutritional impediments to tree growth and impacts on forest health are also reported. This report is intended to contribute to policy deliberations about developing forestry opportunities that can that can be integrated into the landscape, with particular consideration given to lower rainfall regions. There are several examples in north-eastern Australia where production forests have developed sub-optimally; this has often been due to poor selection of tree species as little information has been available. This report helps address this deficiency.

Wood properties and processing outcomes for plantation grown African mahogany (Khaya senegalensis) trees from Clare, Queensland (18 and 20 year-old trees) and Katherine, Northern Territory (14 year-old trees).

Khaya senegalensis, African mahogany, a high-value hardwood, was introduced in the Northern Territory (NT) in the 1950s; included in various trials there and at Weipa, Q in the 1960s-1970s; planted on ex mine sites at Weipa (160 ha) until 1985; revived in farm plantings in Queensland and in trials in the NT in the 1990s; adopted for large-scale, annual planting in the Douglas-Daly region, NT from 2006 and is to have the planted area in the NT extended to at least 20,000 ha. The recent serious interest from plantation growers, including Forest Enterprises Australia Ltd (FEA), has seen the establishment of some large scale commercial plantations. FEA initiated the current study to process relatively young plantation stands from both Northern Territory and Queensland plantations to investigate the sawn wood and veneer recovery and quality from trees ranging from 14 years (NT – 36 trees) to 18-20 years (North Queensland – 31 trees). Field measures of tree size and straightness were complemented with log end splitting assessment and cross-sectional disc sample collection for laboratory wood properties measurements including colour and shrinkage. End-splitting scores assessed on sawn logs were relatively low compared to fast grown plantation eucalypts and did not impact processing negatively. Heartwood proportion in individual trees ranged from 50% up to 92 % of butt cross-sectional disc area for the visually-assessed dark coloured central heartwood and lighter coloured transition wood combined. Dark central heartwood proportion was positively related to tree size (R2 = 0.57). Chemical tests failed to assist in determining heartwood – sapwood boundary. Mean basic density of whole disc samples was 658 kg/m3 and ranged among trees from 603 to 712 kg/m3. When freshly sawn, the heartwood of African mahogany was orange-red to red. Transition wood appeared to be pinkish and the sapwood was a pale yellow colour. Once air dried the heartwood colour generally darkens to pinkish-brown or orange-brown and the effect of prolonged time and sun exposure is to darken and change the heartwood to a red-brown colour. A portable colour measurement spectrophotometer was used to objectively assess colour variation in CIE L*, a* and b* values over time with drying and exposure to sunlight. Capacity to predict standard colour values accurately after varying periods of direct sunlight exposure using results obtained on initial air-dried surfaces decreased with increasing time to sun exposure. The predictions are more accurate for L* values which represent brightness than for variation in the a* values (red spectrum). Selection of superior breeding trees for colour is likely to be based on dried samples exposed to sunlight to reliably highlight wood colour differences. A generally low ratio between tangential and radial shrinkages was found, which was reflected in a low incidence of board distortion (particularly cupping) during drying. A preliminary experiment was carried out to investigate the quality of NIR models to predict shrinkage and density. NIR spectra correlated reasonably well with radial shrinkage and air dried density. When calibration models were applied to their validation sets, radial shrinkage was predicted to an accuracy of 76% with Standard Error of Prediction of 0.21%. There was also a strong predictive power for wood density. These are encouraging results suggesting that NIR spectroscopy has good potential to be used as a non-destructive method to predict shrinkage and wood density using 12mm diameter increment core samples. Average green off saw recovery was 49.5% (range 40 to 69%) for Burdekin Agricultural College (BAC) logs and 41.9% (range 20 to 61%) for Katherine (NT) logs. These figures are about 10% higher than compared to 30-year-old Khaya study by Armstrong et al. (2007) however they are inflated as the green boards were not docked to remove wane prior to being tallied. Of the recovered sawn, dried and dressed volume from the BAC logs, based on the cambial face of boards, 27% could potentially be used for select grade, 40% for medium feature grade and 26% for high feature grades. The heart faces had a slightly higher recovery of select (30%) and medium feature (43%) grade boards with a reduction in the volume of high feature (22%) and reject (6%) grade boards. Distribution of board grades for the NT site aged 14 years followed very similar trends to those of the BAC site boards with an average (between facial and cambial face) 27% could potentially be used for select grade, 42% for medium feature grade, 26% for high feature grade and 5% reject. Relatively to some other subtropical eucalypts, there was a low incidence of borer attack. The major grade limiting defects for both medium and high feature grade boards recovered from the BAC site were knots and wane. The presence of large knots may reflect both management practices and the nature of the genetic material at the site. This stand was not managed for timber production with a very late pruning implemented at about age 12 years. The large amount of wane affected boards is indicative of logs with a large taper and the presence of significant sweep. Wane, knots and skip were the major grade limiting defects for the NT site reflecting considerable amounts of sweep with large taper as might be expected in younger trees. The green veneer recovered from billets of seven Khaya trees rotary peeled on a spindleless lathe produced a recovery of 83% of green billet volume. Dried veneer recovery ranged from 40 to 74 % per billet with an average of 64%. All of the recovered grades were suitable for use in structural ply in accordance to AS/NZ 2269: 2008. The majority of veneer sheets recovered from all billets was C grade (27%) with 20% making D grade and 13% B grade. Total dry sliced veneer recovery from the logs of the two largest logs from each location was estimated to be 41.1%. Very positive results have been recorded in this small scale study. The amount of colour development observed and the very reasonable recoveries of both sawn and veneer products, with a good representation of higher grades in the product distribution, is encouraging. The prospects for significant improvement in these results from well managed and productive stands grown for high quality timber should be high. Additionally, the study has shown the utility of non-destructive evaluation techniques for use in tree improvement programs to improve the quality of future plantations. A few trees combined several of the traits desired of individuals for a first breeding population. Fortunately, the two most promising trees (32, 19) had already been selected for breeding on external traits, and grafts of them are established in the seed orchard.

Controlling fly strike and louse infections in sheep with tea tree oil

This study aimed to assess the effect of tea tree oil based formulations against two major ectoparasitic diseases in the sheep industry, flystrike and louse infestation, and to provide data to assist the assessment of the commercial feasibility of development of tea tree oil based ectoparasiticides. The results demonstrate insecticidal effects against both sheep lice and blowflies and repellent effects against adult flies and maggots. Dipping sheep in a Tea Tree Oil based formulation appeared to completely eradicate lice and suggests its potential use in sheep dipping formulations. Repellent and insecticidal effects against sheep blowflies, together with previously reported anti-microbial and wound healing properties, suggest significant benefits from the inclusion of tea tree oil in flystrike and wound treatment formulations. These effects occurred at concentrations of Tea Tree Oil that suggest the commercial viability of development of Tea Tree Oil based formulations for sheep parasite control and wound treatment and a potential new market for Tea Tree Oil.

Use of tea tree oil against buffalo flies in cattle

Testing tea tree oil against buffalo flies on cattle.

Tropical peach breeding and evaluation

Breeding new peach and nectarine cultivars that are adapted to tropical climates and produce fruit of high quality.

Marker development for genes controlling mango tree architecture

Identification of candidate genes controlling, mango tree architecture.

Marker Assisted Breeding Support for Tropical Horticulture and Forestry in far north Queensland

Molecular marker development for tropical fruit and forestry species.