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The Farm Scale Evaluations of genetically modified herbicide-tolerant crops (GMHT) were conducted in the UK from 2000 to 2002 on beet (sugar and fodder), spring oilseed rape and forage maize. The management of the crops studied is described and compared with current conventional commercial practice. The distribution of field sites adequately represented the areas currently growing these crops, and the sample contained sites operated at a range of management intensities, including low intensity. Herbicide inputs were audited, and the active ingredients used and the rates and the timings of applications compared well with current practice for both GMHT and conventional crops. Inputs on sugar beet were lower than, and inputs on spring oilseed rape and forage maize were consistent with, national averages. Regression analysis of herbicide-application strategies and weed emergence showed that inputs applied by farmers increased with weed densities in beet and forage maize. GMHT crops generally received only one herbicide active ingredient per crop, later and fewer herbicide sprays and less active ingredient (for beet and maize) than the conventional treatments. The audit of inputs found no evidence of bias.

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This paper reviews the major issues that impact upon the development of improved fodder species for saline environments across temperate Australia. It describes past and present research that has been, or is being, undertaken towards improvements in salt tolerance in forage species within Australia in relation to the principal regions where salinity occurs. It includes a discussion on the mechanisms of salt tolerance in plants. An extensive list of known or potential salt-tolerant fodder species is provided and the key opportunities for advancement within each of the 4 major forage groups: grasses, legumes, herbs and shrubs are discussed. Constraints to developing new salt and waterlogging tolerant fodder species are identified. A number of recommendations are made for research that should ensure that Australian producers have access to a new array of productive fodder species suited to saline environments.

Polyphenols in sorghum grains are a source of dietary antioxidants. Polyphenols in six diverse sorghum genotypes grown under two day/night temperature regimes of optimal temperature (OT, 32/21 °C and high temperature (HT, 38/21 °C) were investigated. A total of 23 phenolic compounds were positively or tentatively identified by HPLC-DAD-ESIMS. Compared with other pigmented types, the phenolic profile of white sorghum PI563516 was simpler, since fewer polyphenols were detected. Brown sorghum IS 8525 had the highest levels of caffeic and ferulic acid, but apigenin and luteolin were not detected. Free luteolinidin and apigeninidin levels were lower under HT than OT across all genotypes (p ≤ 0.05), suggesting HT could have inhibited 3-deoxyanthocyanidins formation. These results provide new information on the effects of HT on specific polyphenols in various Australian sorghum genotypes, which might be used as a guide to grow high antioxidant sorghum grains under projected high temperature in the future.

SU MMARYWinter waterlogging is expected to become an increasingly serious problem due to climate change. It is therefore important to find whether differences in tolerance to waterlogging exist between wheat cultivars grown in the UK. Screening experiments were conducted outdoors and in a glasshouse to investigate the yield response to waterlogging and waterlogging tolerance at the seedling stage. The experiments suggested that differences in tolerance existed between cultivars, in the form of digression of some cultivars from their expected yield in the outdoor experiment and a significant interaction between cultivar and waterlogging for shoot and root dry weight in the seedling experiment. Cultivars that appeared to differ in their responses to waterlogging were further tested in a field experiment over two seasons and in a second glasshouse seedling experiment. However, there was no significant relationship between measurements taken at the seedling stage and grain yield at maturity ; also the field experiment did not provide compelling evidence of differences in tolerance. Cultivars with the largest yield suffered the largest decrease due to waterlogging, and the yield of the cultivar with the lowest yield potential was unaffected. All cultivars showed considerable ability to compensate for winter waterlogging damage by vigorous spring growth. All cultivars produced nodal roots in response to waterlogging, and these displayed evidence of aerenchyma tissue by penetrating below the water level, but no cultivar was any better in this respect than any other. The results of these experiments suggest that screening for waterlogging tolerance at the seedling stage is not representative of final yield. It is suggested that the lack of diversity for tolerance is a result of the inbred nature of UK wheat cultivars and that the overall good level of tolerance and ability to compensate has been selected for, either inadvertently, or as a result of selecting the best cultivars in UK conditions, where tolerance to waterlogging is a part of the general winter hardiness required.

BackgroundIt has been predicted that the global temperature will rise in the future, which means crops including sorghum will likely be grown under higher temperatures, and consequently may affect the nutritional properties.MethodsThe effects of two growth temperatures (OT, day/night 32/21°C; HT 38/21°C) on tannin, phytate, mineral, and in vitro iron availability of raw and cooked grains (as porridge) of six sorghum genotypes were investigated.ResultsTannin content significantly decreased across all sorghum genotypes under high growth temperature (P ≤0.05), while the phytate and mineral contents maintained the same level, increased or decreased significantly, depending on the genotype. The in vitro iron availability in most sorghum genotypes was also significantly reduced under high temperature, except for Ai4, which showed a pronounced increase (P ≤0.05). The cooking process significantly reduced tannin content in all sorghum genotypes (P ≤0.05), while the phytate content and in vitro iron availability were not significantly affected.ConclusionsThis research provides some new information on sorghum grain nutritional properties when grown under predicted future higher temperatures, which could be important for humans where sorghum grains are consumed as staple food.

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