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Climate variability, cultivar, and sowing date are some of the factors affecting the yield and productivity of a given crop. Evaluating the effect of all these factors, and their combination, through field experimentation is not always feasible. However, validated crop models are efficient and economically effective tools to analyze the influence these factors have on crop yield and production. The APSIM program is one of such models which are widely used to simulate crop yield and resource-use under different scenarios. In this study, the APSIM-CANOLA module, with long-term climate records, was used to examine the effects of seasonal variability, sowing date and plant available water at sowing on grain yield of several canola cultivars. There was high year to year variability of simulated crop yield in response to the amount of rain. Water use efficiency was found to be cultivar dependent. Sowing date affects the length of crop growing season and hence crop yield. Higher starting soil water significantly contributes to crop production. Break-even canola grain yields were attainable with high probability but higher yields were increasingly less probable and unattainable with some cultivars and under certain sowing and rainfall conditions. [ABSTRACT FROM AUTHOR]

Wild white lupins have high levels of alkaloids, which cause a bitter taste, whereas domesticated white lupin varieties have a very low content of alkaloids in seeds. Genes for bitterness from wild white lupins are a contamination threat to domesticated white lupin via cross-pollination. The gene(s) for alkaloid synthesis have not been clearly identified, and the associated molecular background among wild white lupin, domesticated and contaminated domesticated plant materials is unknown. So far, only tigloyl-CoA:(−)-13alpha-hydroxymultiflorine/(+)-13alpha-hydroxylupanine O-tigloyltransferase (HMT/HLTase) cDNA has been cloned based on protein analysis, which was suggested as encoding a quinolizidine alkaloid transferase regulating quinolizidine alkaloid biosynthesis. This gene has not yet been well characterised in important white lupin genotypes. In this study, we found that the majority of the intron sequence of the HMT/HLTase gene differed between wild white lupin accessions P25758 and P27593, and between the commercial varieties. The expression pattern as well as the expression level of the HMT/HLTase gene showed no difference between the P25758 and the low-alkaloid variety Kiev mutant, suggesting the expression of the HMT/HLTase gene has no correlation with bitterness. However, the intron sequence is useful as a DNA marker in the identification of the contamination source of bitter seeds in commercial lupin seed lots. [ABSTRACT FROM AUTHOR]

A number of methods have been published for barley (Hordeum vulgare L.) anther culture and have gained acceptance in different laboratories. The breeder's requirement is for a compromise method that gives good, repeatable results for a wide range of genotypes. Yet the routine production of spontaneously doubled haploid green regenerants remains difficult. Despite attempts to formulate a widely-applicable anther culture method, the 4 main published methods, compared here with one modified procedure, are quite distinct for a number of important characteristics. The methods interacted strongly with the 3 genotypes, and response ranged from zero to 28 green regenerants per 100 anthers plated. The current methods still require often substantial modification to suit local situations in order that the technology may be exploited by barley breeders.