Cereals are cultivated grasses that are grown throughout the world. As well as providing food for man, they, or fractions derived from processing them, make an important contribution to the diets of farm stock. Cereal grains have a long storage life under favourable conditions because they are harvested at a relatively low moisture content and comprise stable components. The principal energy sources within the grains are protected from infestation by outer coverings that are difficult to penetrate and in some cases unpalatable components in the coverings discourage predation by wild populations. The largest morphological component of all grains is the starchy endosperm, and approximately 80% of this is starch, occurring as microscopical granules with forms characteristic of the species. Also characteristic of the species are the storage proteins, which make the next largest contribution to endosperm dry weight. Proteins are important both as nutrients and by virtue of the fact that the class includes enzymes which, although making a small contribution to grain weight, can have a marked effect on grain quality and hence price. Other chemical components present as minor contributors, but with potential for exerting significant nutritional influence, are phytates and tannins, and current knowledge of these is briefly discussed. The walls of endosperm cells comprise a complex mixture of polysaccharides including cellulose, arabinoxylans, and β-glucans, as well as proteins and esterified phenolic acids. Attention is drawn to the difficulty in defining ‘fibre’ as it is method- or function-dependent and includes contributions from the endosperm cell wall components as well as the lignified walls of cells in the outer protective pericarp and the contents and cuticle of the testa.

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The effect of stripe rust on the processing quality of Australian wheat varieties was examined over a four year period. Each year in field experiments, stripe rust was allowed to develop naturally on one half of each plot block while the other was kept disease free using three weekly applications of fungicide. Changes in grain quality were observed with susceptible varieties when subjected to an epiphytotic of the disease. Stripe rust caused kernels to be shrivelled, which resulted in reduced test weight and flour milling yield and increased grain protein content. Dough properties were also affected. Dough development time was shorter, mixing tolerance deteriorated and extensograph maximum resistance was lower for susceptible varieties affected by the disease.

Dry matter accumulation was determined in 27 chickpea (Cicer arietinum) lines in time-of-sowing ®eld trials and in controlled-environment chambers at day/night temperatures of 13/5, 18/8 and 23/13°C to assess tolerance to growth-inhibiting temperatures. Field trials were based at Narrabri, NSW, Australia, in a region of summer-dominant rainfall where winter crops are grown on stored soil moisture. Percentage emergence was lower than expected in some ®eld trials and in the coolest controlled environment. Subsequent dry matter accumulation showed the eects of poor crop establishment until the onset of¯owering. Kabuli types were more susceptible to poor emergence than desi types. Dierent lines yielded the greatest dry matter production at dierent stages of growth. In the seedling phase, to 30 days after emergence, kabuli accessions SP1.563 and Garnet showed signi®cantly greater dry matter accumulation than all other accessions in all controlled environments, suggesting broad adaptation. One desi accession, Gully, was almost as productive as these two kabuli accessions in the intermediate environment but was much poorer in the other environments, indicating very narrow adaptation. In the vegetative phase, the greatest relative growth rates were found in the desi accessions. Line 940-26 was identi®ed as highly productive in both ®eld and controlled-environment experiments. Dry matter accumulation was not signi®cantly aected by temperature, although it was slightly greater in the coolest controlled environment than in the other two. The accession by temperature interaction was not signi®cant, showing that the breadth of adaptation was similar in all accessions during this growth phase. The optimum time of sowing for dry matter accumulation was late May, 4±6 weeks before the winter solstice. The results showed that chickpeas are well adapted to germination and seedling establishment in moderate conditions, followed by vegetative growth in cooler conditions. These conditions are typical following autumn sowing in a Mediterranean or temperate environment. Kabuli types appear to have stronger growth during the seedling phase and desi types during the vegetative phase. Recombination of these traits could lead to more productive cultivars.

A set of 29 advanced breeding lines and named cultivars from different breeding programs in Australia was compared with 18 genotypes developed by the CIMMYT/ICARDA breeding programs for their adaptation and yield performance using 5 locations in the WANA region for 2 years. Classification analysis identified 13 CIMMYT/ICARDA genotypes that had a pattern in yield performance similar to 2 Australian cultivars, Leichhardt and Hartog. The classification of environments effectively identified trials that experienced heat stress and received supplementary irrigation. Most of the genotypes developed by the CIMMYT/ICARDA breeding programs showed wide adaptation in the WANA region. Genotypes developed for Australian Mediterranean environments failed to show wide adaptation in the WANA region. However, many Australian genotypes showed specific adaptation to heat-stressed environments. Variation among Australian genotypes for disease resistance and heat tolerance couldbe used for wheat improvement in the WANA region.