The new breeding line BL 2006-221 has the potential to be used in the development of phytochemically rich strawberry cultivars. Using hue angle as a screening tool for total anthocyanin concentration and extraction of anthocyanins from strawberries by ASE at 40 °C would support such cultivar development.

No abstract

No abstract

Fusarium wilt of strawberry, incited by Fusarium oxysporum f. sp. fragariae (Fof), is a major disease of the cultivated strawberry (Fragaria ×ananassa) worldwide. An increase in disease outbreaks of the pathogen in Western Australia and Queensland plus the search for alternative disease management strategies place emphasis on the development of resistant cultivars. In response, a partial incomplete diallel cross involving four parents was performed for use in glasshouse resistance screenings. The resulting progeny were evaluated for their susceptibility to Fof. Best-performing progeny and suitability of progenies as parents were determined using data from disease severity ratings and analyzed using a linear mixed model incorporating a pedigree to produce best linear unbiased predictions of breeding values. Variation in disease response, ranging from highly susceptible to resistant, indicates a quantitative effect. The estimate of the narrow-sense heritability was 0.49 ± 0.04 (se), suggesting the population should be responsive to phenotypic recurrent selection. Several progeny genotypes have predicted breeding values higher than any of the parents. Knowledge of Fof resistance derived from this study can help select best parents for future crosses for the development of new strawberry cultivars with Fof resistance.

Papaya ringspot virus type W (PRV-W) causes foliar mosaic, deformed fruit and reduced yield in crops of Cucurbita maxima cv. Queensland Blue in Queensland. Cucurbita ecuadorensis is highly resistant to PRV-W. Using crosses between these 2 cucurbits we studied inheritance of resistance to PRV-W in mechanically inoculated parental, F1, F2, backcross and inbred backcross populations under glasshouse and/or field conditions. Disease severity was assessed on each plant as the proportion of the young leaf area which was chlorotic. Inheritance of resistance, following inoculation of cotyledons with either of 2 isolates that differed in the severity of symptoms produced, was most consistently described as polygenic. Analysis of means of generations indicated additive gene effects were predominant. However simpler inheritance could not be entirely discarded as a 13:3 digenic model based on epistasis and modifiers described some distributions. No strong associations existed between high resistance to PRV-W and undesirable characteristics so that transfer of high levels of resistance from C. ecuadorensis to commercially acceptable lines of C. maxima should be possible.