'Banksia' species (Plate I) have been cultivated for the international cut flower market for only 20 to 30 years, but there is increasing interest in areas other than the native home, Australia, with production in Israel, South Africa, Hawaii, and California (Ben-Jaacov 1986; Sedgley 1996). Within Australia, 'Banksia' is one of the four most widely planted commercial native genera, but production is based on seedling material and between plant variability is high. 'Banksia' species for the fresh cut flower market must fulfill strict commercial criteria, which include terminal blooms and long stem length (Fig. 1.1), and further research is needed into all aspects of 'Banksia' biology and production. In addition to the fresh cut flower market, 'Banksia' stems are traded as dried and dyed blooms, and a wide range of species is used in environmental horticulture, for the attractive inflorescences and foliage, and to attract birds and other wildlife. Although there has been little work conducted so far on the use of banksias as pot plants, recent developments with related genera suggest that such an approach may be productive (Ben-Jaacov et al. 1989). 'Banksia' wood and cones are turned or incorporated into ornaments, and the timber of some species has been used for furniture.

An integrated molecular linkage map of olive (Olea europaea L.) was constructed based on randomly amplified polymorphic DNA (RAPD), sequence characterized amplified region (SCAR), and microsatellite markers using the pseudo-testcross strategy. A mapping population of 104 individuals was generated from an F1 full-sib family of a crossbetween 'Frantoio' and 'Kalamata'. The hybridity of the mapping population was confirmed by genetic similarity and nonmetric multidimensional scaling. Twenty-three linkage groups were mapped for 'Kalamata', covering 759 cM of the genome with 89 loci and an average distance between loci of 11.5 cM. Twenty-seven linkage groups were mapped for 'Frantoio', covering 798 cM of the genome with 92 loci and an average distance between loci of 12.3 cM. For the integrated map, 15 linkage groups covered 879 cM of the genome with 101 loci and an average distance between loci of 10.2 cM. The size of the genomic DNA was estimated to be around 3000 cM. A sequence characterized amplified region marker linked to olive peacock disease resistance was mapped to linkage group 2 of the integrated map. Thesemaps will be the starting point for studies on the structure, evolution, and function of the olive genome. When the mapping progeny pass through their juvenile phase and assume their adult characters, mapping morphological markers and identification of quantitative trait loci for adaptive traits will be the primary targets.

The genus 'Eucalyptus' contains many species suitable for the floriculture and amenity horticulture industries in Australia. A development program has been underway at the University of Adelaide, with the aim of producing new and novel hybrid eucalypt varieties for these industries through controlled pollination between selected ornamental species. As each new hybrid plant reaches reproductive maturity, it is assessed for desirable characters and the very best plants selected for further development, including response to production systems and vegetative propagation. Plants that perform well in cultivation and can be propagated vegetatively will be registered with Plant Breeders Rights and made available through commercial nurseries.

Background and Aims: Following our original discovery of star flowers on grapevines in Australia, further variants of the star flower phenotype have been discovered on other varieties in South Australia. The objective of this report was to describe star flowers on 'Vitis vinifera' L. cvs Chardonnay and Shiraz. Methods and Results: Field and microscopic observations revealed that star flowers on both varieties opened precociously; there was neither pollen nor pollen tubes on the stigmas of the star flowers, and both Chardonnay and Shiraz star flowers contained aberrant ovules. The Chardonnay vines with star flowers produced bunches with an abundance of seedless berries; however, star flowers on Shiraz vines did not develop into berries. Conclusions: The inability of the Shiraz star flowers to develop into berries suggests that either there are two different mutations affecting these two varieties, or else the difference lies in their contrasting parthenocarpic tendencies. Significance of the Study: The star flower variants described here and previously may be the result of deviations to the normal molecular pathway for flower development in 'Vitis' species. The identification of star flowers on numerous varieties and in several different regions suggests that the occurrence of star flowers may be more widespread than previously realised, and the association of star flowers with the production of seedless berries and poor fruitset suggests that star flowers may also play a significant role in the problem of poor fruitset.

The secondary metabolite amygdalin is a cyanogenic diglucoside that at high concentrations is associated with intense bitterness in seeds of the Rosaceae, including kernels of almond ('Prunus dulcis' (Mill.), syn. 'Prunus amygdalus' D.A. Webb Batsch). Amydalin is a glucoside of prunasin, itself a glucosider of 'R'-mandelonitrile (a cyanohydrin). Here we report the isolation of an almond enzyme (UGT85A19) that stereo-selectively gucosylates 'R'-mandelonitrile to produce prunasin. In a survey of developing kernels from seven bitter and 11 non-bitter genotypes with polyclonal antibody raised to UGT85A19, the enzyme was found to accumulate to higher levels in the bitter types in later development. This differential accumulation of UGT85A19 is associated with more than three-fold greater mandelonitrile glucosyltrajsferase activity in bitter kernels compared with non-bitter types, and transcriptional regulation was demonstrated using quantitative-PCR analysis. UGT85A19 and its encoding transcript were most concentrated in the testa (seed coat) of the kernel compared with the embryo, and prunasin and amygdalin were differentially compartmentalised in these tissues. Prunasin was confined to the testa and amygdalin was confined to the embryo. These results are consisted with the seed coat being an important site of synthesis of prunasin as a precursor of amygdalin accumulation in the kernel. The presence of UGT85A19 in the kernel and other tissues of both bitter and non-bitter types indicates that its expression is unlikely to be a control point for amygdalin accumulation and suggests additional roles for the enzyme in almond metabolism.

The influence of flower position on the inflorescence on opening day, gender, and petal persistence was studied in three olive cultivars: Manzanillo, Mission, and Frantoio. In each cultivar, 45 inflorescences were checked every morning from flower opening to petal fall. Perfect flowers opened mainly in the beginning of the flower opening period, and staminate flowers opened later. Flower position on the inflorescence had a highly significant effect on the opening day in all cultivars. Terminal flowers and the flowers located on the primary branches opened earlier than the flowers located on the secondary branches. Flower position had also a highly significant effect on gender in Manzanillo and Mission. In Manzanillo, the secondary branches had fewer perfect flowers than the primary branches. In Mission, the secondary branches had no perfect flowers at all. Among the primary branches, the branch arising immediately next to the terminal flower had the latest flowers to open and the lowest percent of perfect flowers. In Manzanillo, perfect flowers had significantly longer petal persistence than staminate flowers. To study flower competition within the inflorescence, the distal half of 120 inflorescences, on which the flowers tend to be perfect, in three trees of Manzanillo were removed about 1 month before full bloom. There was a highly significant effect on the percent of perfect flowers that opened on the proximal half. Flower competition may be a reason for pistil abortion in flowers located on secondary branches.

We examined the relationship between shoot growth and temperature and solar radiation in macadamia ('Macadamia integrifolia' Maiden and Betche, M. 'integrifolia X tetraphylla' Johnson) as an aid to developing pruning strategies for this crop. Trees growing at Alstonville (28.9°S) in northern NSW, Australia, were pruned at various times to promote vegetative flushing under a range of environmental conditions. Flush development in macadamia is cyclic: bud release and stem elongation followed by a period of dormancy, before bud release of the subsequent flush. The rate of bud release after pruning was best correlated with the product of the mean temperature and solar radiation (r² = 0.75, P < 0.0001), whereas the rate of flush development was best correlated with the mean temperature (r² = 0.76, P < 0.0001). The number of buds released per pruned stem was greater under higher temperatures and solar radiation (r² = 0.37, P < 0.001), but the length of the flush after pruning decreased with increasing temperatures (r² = 0.32, P < 0.01). The descriptive models were combined with long-term weather data to predict the duration and characteristics of flushes following pruning at various times of the year along Australia’s eastern seaboard, from Mareeba (17.0°S) to Coffs Harbour (30.38°S). Flush duration and stem length following June pruning were predicted to be greater than following early autumn or September pruning and to vary from year to year, and with location (latitude). We discuss the implications of the model predictions for productivity and propose pruning times intended to optimise flowering and yield. Further research is required to test these proposed pruning strategies.

Micropropagation via enhanced axillary shoot proliferation was investigated in the ornamental Eucalyptus cv. 'Urrbrae Gem' using in vitro germinated seedlings and was successfully achieved using woody plant medium (WPM) supplemented with 2.2 μM benzylaminopurine, 1.0 μM α-naphthaleneacetic acid, and 1.5 μM gibberellic acid (GA₃), gelled with 5 g l−1 Phytagel®. Shoot proliferation was greater on WPM and QL media with GA3 compared to B5, AP, and TK media with or without GA3. GA3 was required for shoot elongation as the internodes were otherwise very short and unsuitable for multiplication or root initiation. Root initiation was improved using (1/2) WPM supplemented with 20 μM indole-3-butyric acid (IBA) over a 7 d pulse, followed by subculture to IBA-free medium, compared to placing shoots on low levels of IBA for 4–6 wk. Plantlets were successfully hardened off to the natural environment via a fogger at 67% relative, humidity at 21°C for 3 d and continued to thrive as potted plants. This is the first report of successful, micropropagation in an ornamental eucalypt (subgenus Symphyomyrtus) from seedling explants.

Organogenesis and somatic embryogenesis were investigated in apex and cotyledon explants of 'Eucalyptus erythronema, E. strick landii' and their inter-specific hybrids 'Eucalyptus erythronema' X E. 'stricklandii cv'. 'Urrbrae Gem' and 'Hybrid 2.5', following exposure to 1 mg 1-¹ naphthaleneacetic acid (NAA) plus 1 mg 1-¹ 2,4dichlorophenoxyacetic acid (2,4-0), or 3, 5 or 15 mg 1-¹ NAA alone. Somatic embryogenesis was not observed macroscopically; however, structures characteristic of globular somatic embryos or root primordia were observed using light microscopy of apex explants of 'Urrbrae Gem' seedlings after 14 d on Murashige and Skoog (1962) (MS) medium supplemented with 3 mg 1-¹ NAA. Root development was associated with explant vascular tissue and observed in all plant growth regulator (PGR) treatments, but was less on explants treated with 1 mg 1-¹ NAA plus 1 mg 1-¹ 2,4-0 than in all NAA-alone treatments. Shoot development was observed on apex explants after sub-culture on PGR-free medium, but was less after treatment with 1 mg 1-¹ NAA plus 1 mg 1-¹ 2,4-0 compared to all NAA-on1y treatments. Roots and sho ts developed simultaneously on apex explants after culture for 1 week on MS medium supplemented with 15 mg 1-¹NAA.

The olive research program at the University of Adelaide is focused on the selection of improved olive cultivars. Superior selections have been obtained from populations of feral olives that have escaped from cultivation and now grow wild throughout the southern areas of Australia. Several trees have been deemed 'superior' based on oil yield and quality data obtained by Soxhelt extraction, gas chromatography and organoleptic assessment. Techniques developed for analysing new selections will also be used to provide quality assurance to the Australian olive industry.Cultivar identification of Australian and international accessions is a routine practice using DNA fingerprinting by random amplified polymorphic DNA (RAPID) analysis.A genetic marker linked to peacock spot disease resistance was identified using bulked segregant analysis and a linkage map for olive has been generated that will be used to locate further molecular markers linked to agronomic traits. These markers will be used on new selections to make predictions about their performance under long-term cultivation. We have also investigated the degree of cross- and self-incompatibility between the cultivars Frantoio, Manzanillo, Kalamata, Pendolino and Picual, using a 5 x 5 diallel cross.