Genetic advances in grain yield under rainfed conditions have been achieved by empirical breeding methods. Progress is slowed, however, large genotype x season and location interactions arising from unpredictable rainfall, which a feature of dry environments. A good understanding factors limiting and/or regulating now provides us with an opportunity to identify then select for physiological morphological traits that increase the efficiency water use conditions. The incorporation these into...

Greater yield per unit rainfall is one of the most important challenges in dryland agriculture. Improving intrinsic water-use efficiency (W(T)), ratio CO(2) assimilation rate to transpiration at stomata, may be means achieving this goal. Carbon isotope discrimination (Delta(13)C) recognized as a reliable surrogate for W(T) and there have now been numerous studies which examined relationship between crop (measured Delta(13)C). These shown highly variable. The impact on genotypic variation...

Genetic gain is characteristically slow when selecting directly for increased grain yield under water‐limited conditions. increases in may be achieved through aerial biomass following selection greater transpiration efficiency (TE as biomass/water transpired). Strong negative correlations between TE and carbon isotope discrimination (Δ) wheat ( Triticum aestivum L.) suggest that of progeny with low Δ increase This study investigated how early generation, divergent affected among 30 low‐...

Consistent gains in grain yield dry environments have been made by empirical breeding although there is disturbing evidence that these may slowed. There are few examples where an understanding of the physiology and genetics putative important drought-related traits has led to improved yields. Success will first depend on identifying most target regions. It then accurate fast phenotyping, which, turn, lead to: (1) trait-based selection being immediately transferable into operations (2) able...

There is little consensus on whether having a large root system the best strategy in adapting wheat (Triticum aestivum L.) to water-limited environments. We explore reasons for lack of and aim answer question useful dry used unpublished data from glasshouse field experiments examining relationship between size their functional implication water capture. Individual traits uptake do not describe as being or small. However, recent invigoration by indirect selection increased leaf vigour has...

Crop improvement efforts are targeting increased above-ground biomass and radiation-use efficiency as drivers for greater yield. Early ground cover canopy height contribute to production, but manual measurements of these traits, in particular biomass, slow labour-intensive, more so when made at multiple developmental stages. These constraints limit the ability capture data a temporal fashion, hampering insights that could be gained from multi-dimensional data. Here we demonstrate capacity...

Durum wheat (AB genomes) is more salt-sensitive than bread (ABD genomes), a feature that restricts its expansion into areas with sodic or saline soils. Salt tolerance in linked locus on the D genome results low Na+ uptake and enhanced K+/Na+ discrimination. In order to introduce salt current durum wheats from sources other genome, search for genetic variation was made across wide range of tetraploids representing 5 Triticum turgidum sub-species (durum, carthlicum, turgidum, turanicum,...

Grain yield potential of Australian wheat crops is often limited because inadequate water for crop growth and grain filling. Greater early vigour, defined here as the amount leaf area produced in season, should improve water-use efficiency grown Mediterranean-type climates such occurs southern Australia. In order to maximise selection vigour breeding programs, magnitude form genetic variation its components was investigated 2 contrasting populations. The first population comprised 28...

Greater yield per unit rainfall is one of the most important challenges in dryland agriculture. Improving intrinsic water-use efficiency (WT), ratio CO2 assimilation rate to transpiration at stomata, may be means achieving this goal. Carbon isotope discrimination (Δ13C) recognized as a reliable surrogate for WT and there have now been numerous studies which examined relationship between crop (measured Δ13C). These shown highly variable. The impact on genotypic variation will depend three...

Genetic advances in grain yield under rainfed conditions have been achieved by empirical breeding methods. Progress is slowed, however, large genotype × season and location interactions arising from unpredictable rainfall, which a feature of dry environments. A good understanding factors limiting and/or regulating now provides us with an opportunity to identify then select for physiological morphological traits that increase the efficiency water use conditions. The incorporation these into...

Genes that reduce height without compromising seedling vigour or coleoptile length have great potential for wheat improvement. We therefore investigated the effects of various reduced (Rht) genes on early stages plant development, using a combination near isogenic, recombinant, mutant and wild type comparisons. Gibberellin (GA) insensitivity caused by Rht-B1b Rht-D1b was associated with leaf elongation rate length. Similar results were found two other sources dwarfing, Rht11 Rht17. one class...

The water-soluble carbohydrate (WSC) that accumulates in the stems of wheat during growth can be an important contributor to grain filling, particularly under conditions when assimilation is limited, such as end-of-season drought. WSC concentration was measured at anthesis across a diverse set genotypes over multiple environments. Environmental differences were large (means for ranging between 108 and 203 mg g–1 dry weight), there significant repeatable accumulation among from 112 213 weight...

Several environmental factors including drought and disease can reduce leaf area photosynthesis during grain-filling to decrease grain yield kernel weight of cereal crops. Water-soluble carbohydrates (WSC) accumulated around anthesis be mobilised assist in filling developing grains when post-anthesis assimilation is low. Cultivar differences support opportunities select for high WSC but little known the extent or nature genetic control this trait wheat. Three wheat mapping populations...

Stomata are the site of CO2 exchange for water in a leaf. Variation stomatal control offers promise genetic improvement transpiration and photosynthetic rates to improve wheat performance. However, techniques estimating conductance (SC) slow, limiting potential efficient measurement modification this trait. Genotypic variation canopy temperature (CT) leaf porosity (LP), as surrogates SC, were assessed three mapping populations grown under well-watered conditions. The range resulting variance...

Root length and depth determine capture of water nutrients by plants, are targets for crop improvement. Here we assess a controlled-environment wheat seedling screen to speed, repeatability relatedness performance young adult plants in the field. Recombinant inbred lines (RILs) diverse genotypes were grown rolled, moist germination paper growth cabinets, primary root number measured when leaf 1 or 2 fully expanded. For comparison, field systems harvested at two-leaf stage with either shovel...

Abstract Genetically controlled resistance provides plant breeders with an efficient means of controlling disease, but this approach has been constrained by practical difficulties associated combining many genes together and strong evolutionary responses from pathogen populations leading to subsequent breakdown. However, continuing advances in molecular marker technologies are revolutionizing the ability rapidly reliably manipulate resistances all types – major gene, adult quantitative loci...

We aim to incorporate deep root traits into future wheat varieties increase access stored soil water during grain development, which is twice as valuable for yield captured at younger stages. Most phenotyping efforts have been indirect studies in the laboratory, young plant stages, or using shoot measures. Here, coring 2 m depth was used across three field environments directly phenotype on development (depth, descent rate, density, length, and distribution). Shoot phenotypes included canopy...