Twenty-eight Australian wheat (Triticum aestivum L. em. Thell.) cultivars representing a series from the 1860s to 1982, were grown in 20 field trials over four years in the wheatbelt of Western Australia. The cultivars included introductions and selections made before 1900, plus important cultivars bred or grown in Western Australia up to 1982. Five of the latter group were from crosses including semidwarf cultivars as parents. Grain yields were measured on all trials, and six trials were also sampled for biomass and yield components.Based on the regression of mean grain yield versus the number of years elapsed since 1884, yields have increased from 1022 kg ha-1 in 1884 to 1588 kg ha-1 in 1982. This represents a rate of increase of 5.8 kg ha-1 year-1 or 0.57% per year. Regression of cultivar yield on site mean yield gave values of b, the slope of the regression, from 0.66 to 1.24, and these were higher for modern than for old cultivars.In six trials sampled for yield components, above-ground biomass appeared to have increased slightly when comparing early selections and their derivatives with later cultivars, but over 80% of the overall increase in grain yield was due to increase in harvest index. Grains per car and grains m-2 were strongly and positively correlated with grain yield, but there were weak negative correlations between 1000-grain weight and yield, and between 1000 grain weight and years since 1884. Cultivars with a semi-dwarf background had equal biomass, but higher yield, harvest index, ear number m-2 and grains ear-2 than modern tall cultivars. The results show that genetic improvement has substantially increased yield potential in this environment and that this has been achieved through substantial increases in grain number m-2 associated with an improvement in harvest index.

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Maintenance of the size and differentiated function of the adult prostate is dependent on testicular androgens. In this study, simultaneous androgen receptor (AR) immunohistochemistry and [3 H]thymidine labelling was used to characterise the proliferating epithelial cells of the murine ventral prostate. Proliferation in the adult prostate was more prevalent in the basal cell population with 1·8% AR-negative cells labelled with [3 H]thymidine as compared with 0·7% AR-expressing luminal cells. Three weeks following castration of mice, the atrophied prostate contained rudimentary glands composed of both luminal and basal cells with the proportion of AR-expressing basal cells reduced from 50 to 25%. Administration of testosterone enanthate to castrated mice induced a recapitulation of the prostate gland that was preceded by up-regulation of AR expression in basal cells to normal adult levels (50% AR-positive cells) by 12 h following testosterone injection. Proliferation of AR-positive luminal cells peaked at 48 h (22·8%) while proliferation of AR-negative basal cells peaked at 96 h (6·1%) following testosterone administration. These results suggest that distinct populations of luminal and basal cells are resistant to castration-induced involution of the prostate but remain responsive to direct or indirect testosterone effects and recapitulate the gland following administration of testosterone.

a b s t r a c tFaba beans cv. Fiesta with seed moisture content (SMC) modified to 8, 10, 12 and 14% were packed in polyethylene lined aluminium foil bags and stored at 5,15, 20, 25, 30, 37, 45, 50 or 60 C (AE 2 C) for one year. Samples were analysed for moisture content and seed coat (testa) colour over the storage period using a chroma meter. A continuous increase in L * and b * values was found in all samples with the passage of time whereas a * values first increased and then decreased in samples stored at relatively high temperatures (! 37 C). The initial beige testa colour changed to light brown, dark reddish-brown or almost black depending on storage conditions. The higher the temperature and SMC the faster the rate of change in colour (6E ab * values). Seeds with 8% SMC had more stable testa colour compared to seeds with higher SMC.Exposure to artificial light (350 m mol m À2 s À1 ) substantially accelerated the colour darkening. Cotyledons stored at 37 AE 2 C also darkened with the storage time. A loss in total free phenolics, total tannins and proanthocyanidins was found with increased darkness of testa and cotyledons during storage.