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Ancient wheats are valuable genetic resources, though knowledge on their response to micronutrients in the presence of saline irrigation water is scanty. Two studies were conducted to unravel the behavior of ancient emmer and spelt wheats upon exposure to saline (75 and 150 mM NaCl) water and foliar-applied Zn (4 g L− 1) under pot and field conditions. Two weeks after implementing the salt treatment, Zn treatment was implemented twice with one week interval and the plants were exposed to the prolonged salt stress until physiological maturity. Then, an array of physiological processes underlying differential grain yield and quality responses of the ancient and standard wheats to these treatments were scrutinized. Salinity suppressed chlorophyll, relative water content, root volume, stubble yield, and grain yield of emmer and spelt and standard durum and bread wheats. Though, it increased the proline concentration, and Na+/K+ in all wheat genotypes. Emmer wheats indicated smaller salt-induced suppressions in stubble yield and grain yield, despite indicating a greater Na+/K+. Ancient emmer and spelt wheats indicated smaller grain yield components, but out-ranked the standard durum and bread wheats in terms of root volume, grain Zn, and protein concentrations. Zn's effect on the grain yield attributes and grain yield was moderate but it enhanced the grain Zn, particularly in emmer wheats. Novel findings of this study suggest that emmer wheats supplied with foliar-applied Zn are superior to standard durum and bread wheats in terms of grain protein and Zn, root volume, and tolerance to saline water. [ABSTRACT FROM AUTHOR]

The hordoindolina genes (Hina and Hinb) are believed to play critical roles in barley (Hordeum vulgare L.) grain texture. In this study, we created novel alleles of the Hina gene using CRISPR/Cas9 (Clustered regularly inter spaced short palindromic repeat-associated protein, CRISPR-Cas) genome editing. Mutagenesis of single bases in these novel alleles led to loss of Hina protein function in edited lines. The grain hardness index of hina mutants was 95.5 on average, while that of the wild type was only 53.7, indicating successful conversion of soft barley into hard barley. Observation of cross-sectional grain structure using scanning electron microscopy revealed different adhesion levels between starch granules and protein matrix. Starch granules were loose and separated from the protein matrix in the wild type, but deeply trapped and tightly integrated with the protein matrix in hina02 mutants. In addition, the grain width and thousand-grain weight of the hina02 mutant were significantly lower than those of the wild type. [ABSTRACT FROM AUTHOR]

Grain hardness (HI) is a key trait for wheat milling and end-use quality. Puroindoline genes (PINs) are the major genes responsible for grain hardness, but other QTLs also contribute to the trait. Therefore, it is essential to identify loci associated with the HI and allelic variations of PINs in wheat. In the present study, 287 accessions from Shanxi province representing 70 years of wheat breeding were grown in one rainfed and two irrigated conditions to study grain hardness. Genome-wide association analysis (GWAS) was performed using the 15 K array, and the variability of PIN alleles was investigated. Among the accessions, hard wheat was most common. The broad-sense heritability (H2) among the three environments was 99.5%, suggesting HI was mainly affected by heredity. GWAS identified nine significant marker–trait associations (MTAs), including that PINs, which explained 7.03% to 17.70% of phenotypic variation. Four MTAs on chromosome 2A, 2B, 5A, and 7A were novel loci. As for diversity of PINs, a total of 11 PINs haplotypes were detected, composed of 12 allelic variations of the PIN gene. The most frequent haplotypes were Pina-D1a/Pinb-D1b (43.9%) and Pina-Dla/Pinb-D1p (18.8%), and both the frequency of Pina-D1a/Pinb-D1b and the HI value increased with breeding years were related to local dietary habits probably. A novel double deletion allele of the PINs haplotype was found in Donghei1206. These results will be useful not only in understanding of the genetics of the HI but also in breeding for improved grain texture. [ABSTRACT FROM AUTHOR]

Twelve wheat genotypes with variable grain hardness were evaluated for grain, flour, pasting, dough rheological properties, high molecular weight glutenin subunits (HMW-GS) and their relationship with cookie quality characteristics. The degree of hardness played an important role in the expression of characters under study. Genotypes with higher grain hardness index (GHI) showed higher dough development time and dough stability. GHI and solvent retention capacity were positively related to each other and negatively to spread factor. GluD1 locus of majority of hard wheat genotypes showed 5 + 10 subunit while soft wheat (SW) genotypes with 2 + 12 subunit related to gluten quality and dough properties. Overall, variation in subunits at GluD1 locus led to greater variation amongst studied genotypes followed by GluB1 and GluA1. Subunits Null at GluA1, 20, 7 + 8 and 7 + 9 at GluB1, and 2 + 12 and 5 + 10 at GluD1 showed a profound effect on flour, dough and cookie quality. Distribution of different HMW-GS, gluten characteristics and GHI, thus emerged as major parameters for selection of wheat genotypes for development of cookies. SW (QBP 13–11) with the lowest GHI and HMW-GS profile (2*, 7 and 2 + 12 subunit) showed the highest cookie SF and the lowest BS, thereby, turning out to be the best suitable genotype for producing cookies. [ABSTRACT FROM AUTHOR]

Grain quality parameters of winter common wheat under the influence of ha/Ha (hard vs. Soft) genes, determining grain hardness vs. grain softness, as well as genotypes for the Wx-A1, Wx-B1, and Wx-D1 genes, responsible for either amylose or amylopectin type of endosperm starch, were examined. The influence of environmental conditions on the formation of these parameters in different wheat genotypes during grain ripening was demonstrated. It was demonstrated that the grain softness in comparison with the grain hardness and amylopectin form led to a considerable decrease in water absorption capacity (Absorption) of the grain. The environment affects variation of this trait in amylose genotypes, but does not affect absorption in amylopectin forms. Differences in grain hardness affected the gluten parameter, but showed no response to the environmental influence. Genotypes differing in Wx genes had no hereditary effect on this parameter. The influence of environment factors on the formation of this parameter was revealed. In the years favorable for the wheat grain ripening, the values of viscosity and retrogradation indices were considerably lower in amylopectin forms compared to amylose ones. In the conditions of increased humidity during this period, the differences between these groups of genotypes are smoothed out, and very low viscosity and retrogradation index values are observed. Unlike environmental factors, the differences in grain hardness had no effect on these grain quality parameters. The amylase index in amylopectin forms was stable over the years and did not vary in this group of genotypes and also did not differ from that in amylose genotypes. The response of this index to environmental conditions in the groups of amylose-type cultivars was observed. In the years with the weather conditions favorable for wheat ripening, the viscosity index can be used for identification of amylopectin genotypes. [ABSTRACT FROM AUTHOR]

Key Message: Wheat grain texture is a complex trait. The crucial role of puroindoline genes in grain texture determination was confirmed. New loci, highly associated with the trait, were identified and dissected. Grain texture is an important milling characteristic of common wheat. Previously, it was shown that the Ha locus on 5DS, containing the puroindoline-a, puroindoline-b and GSP-1 genes, has a crucial role in endosperm texture. However, some other loci were detected on different chromosomes, but no specific genes were proposed to be involved in grain hardness organization. In this study, we used a panel of Russian spring wheat varieties. The grain texture of varieties ranged from soft to hard. Analysis of the flour particle size and flour particle specific surface of wheat varieties cultivated in different environments demonstrated high heritability (0.79–0.8) and strong repeatability of the traits. Genotyping of wheat varieties with allele-specific markers for the puroindoline-a and puroindoline-b genes demonstrated that 25% of the studied varieties carried rare allele Pin-D1k, which lacked both Pina and Pinb (double null allele). Our results confirmed the strong impact of this allele on grain texture. Association analysis with the use of SNP genotyping (Illumina 15 K Wheat) and 2-year phenotyping confirmed the key role played by puroindoline genes (5D) in determining the grain texture of Russian wheat varieties. The analysis also detected significant SNPs on the 1B, 3A, 5B, 6A, 6D, 7B, 7D chromosomes. The best candidate loci for the grain texture were located on chromosomes 5B and 7B (FDR ≤ 0.05). We dissected a number of candidate genes and proposed a possible mechanism for their contribution to endosperm texture determination. These genes are involved in the metabolism of galactolipids (DGDG) and carbohydrates (1,3-β-glucan). [ABSTRACT FROM AUTHOR]

This investigation determined how changes in chemical composition of malting red and white kaffir sorghum grains dried under the sun affected the resistance of the malts to fracture as determined by the Monsanto Hardness Tester. The sorghum grains were malted by a modification of the 2-step wet steep method and dried under the sun. The results showed that malting increased diastatic activity to peak values of 78.40°L and 56°L in the red and white malts; moisture content from 115 to 165 g/kg and 125 to 170 g/kg, crude protein from 104.20 to 183 g/kg and 92.8 to 153.20 g/kg respectively but decreased the fat content. Grain hardness decreased from 83.20 to 42.50 N in the red malts and from 72.70 to 39.30 N in the white. The increases in diastatic activity, moisture, crude protein and reduced fat contents appear to have contributed most to the reduction in grain hardness. [ABSTRACT FROM AUTHOR]

Wheat has a vital position in agriculture because it is a staple food for masses and variation in grain hardness governs its applications. Soft wheats have softer endosperm texture that mills easily, so needs less energy to mill, produces smaller particles, and small amount of starch is damaged after milling as compared to hard wheat. Soft texture results from higher level of friabilin whereas hard texture results from low level of friabilin on starch granule surface. Friabilin, a marker of kernel texture is primarily composed of Puroindolines (PINs) and its genes ( Pins) are located on the Hardness ( Ha) locus. The Pins are the molecular-genetic basis of kernel softness in wheat. When both Pins are in their 'wild state' ( Pina- D1a and Pinb- D1a), wheat kernel is soft. Absence or mutation in one of the Pins results in hard grain texture with different effects on end use and milling qualities. Pina- D1b genotypes gave harder grain texture, higher protein content, water absorption of flour, damaged starch granules and greater flour yield than hard wheat. Recently, other Pins like genes, Pin b variant genes located on the long arm of chromosome 7A were reported in bread wheat with more than 70% similarity to Pinb ( Pinb- D1a) at the DNA level. Other genes located on chromosomes 1A, 2A, 5A, 7A, 5B, 2D and 6D also affect kernel texture. However the main determinants are the variants in the allelic diversity of Puroindoline family genes. Contemporary studies show that Pins are multifunctional family of genes having a range of functions from grain hardness to natural defense against insects and pathogens such as viruses, bacteria and fungi. [ABSTRACT FROM AUTHOR]

The production of bioplastics directly from wheat flour has been demonstrated to be reliable, but scarce knowledge is available on how flour characteristics may affect the performance of thermoplastic films. In this work, we first established the most suitable recipe and process for the production of extruded films and then we used eight single-cultivar wheat flours with different baking technological properties to assess how they affect the mechanical properties of thermoplastic films. The results have shown that flours from soft grain cultivars offered more rigid and deformable films than flours from hard grain cultivars. For similar hardness, the alveographic P/L ratio of the dough was inversely related to rigidity and directly related to deformability of plastic films, while the deformation energy of the dough (W) played a role only for great differences of it. The subsequent fabrication of blends between each of the flours that yielded the best film properties and polycaprolactone (PCL) at different proportions indicated that a wheat flour/PCL ratio (TWF/PCL) of 75/25 offered the most suitable films for further application. Our results are likely to be useful for improving the plasticization of flour, in that selection of wheat flours could be tailored on the properties desired for the bioplastic films. [ABSTRACT FROM AUTHOR]

The Kazakhstan-Siberia nursery (KASIB) for the spring wheat improvement under the aegis of the CIMMYT (International Maize and Wheat Improvement Center) has been identified for a ten-year period by five cultivar blocks analyzed for the gliadin composition (1B/1R traslocation), compositions of high-molecular weight (HMW) and low-molecular weight (LMW) glutenin subunits, and the grain hardness class. A composition of HMW glutenin subunits is presented according to the Union for Protection of New Varieties of Plants (UPOV) regulations for characteristics 27, 28, and 29 of the system for testing the uniformity, distinctness, and stability of 188 uniform specimens. Most spring wheat varieties are characterized by the formulas '2* 7 + 9 5 + 10' (up to 40% of all uniform varieties), '2* 7 + 9 2 + 12' (up to 30% of all uniform varieties), and '1 7 + 95 + 10' (up to 8% of specimens). In the Kazakhstan gene pool of varieties, the genotypes with the novel 4 + 10 subunit on the 1D chromosome has been detected in the Erythrospermum 55/94-01-20 and Phyton 41 specimens. The Iridost cultivar is identified as a carrier of the comparatively rare 5.5 + 10 allele on the 1D chromosome, which has been previously detected in the Tselinogradka, Tselinnaya 24, and Akmola 3 varieties. A rare 7* + 8 subunit is typical for the E-607 and E-757 genotypes. The specimen uniformity level is the highest in 3 KASIB components (8, 9; 10-11; and 12, 13) and comprises 74-84%. The wheat-rye 1 BL.1RS translocation is predominantly identified in specimens selected at the Siberian Research Institute of Agriculture (SibNIISKhOZ) and the East-Kazakhstan Research Institute of Agriculture (VKNIISKh) and found at each KASIB block; it is indicated in all specimens presented by the Kurgansemena Close Corporation and the Agrosemconsult, LLP, as well as selected at the Fiton, LLP. Cultivars such as Altaiskaya 105, Kurganskaya 5, Lutecsence 1300, Phyton 42, Lutecsence 53/95-98-1, Lutecsence 53/88-94-12, Lutecsence 54, Lutecsence 30-94, Erythrospermum 607, and Aktobe 1574 have been characterized by a wide range of variation in grain hardness from semisoft to hard under different growth conditions. [ABSTRACT FROM AUTHOR]

Durum wheat is the second-most widely grown wheat species, and is primarily used in the production of pasta and couscous. The grain utilization of durum wheat is partly related to its very hard kernel texture because of the lack of the D genome and consequentially the Puroindoline genes. Our previous study reported the transformation of durum wheat with the Puroindoline a ( Pina) gene. Here, we characterized the transgenic durum wheat lines expressing the Pina gene, and studied the effects of PINA on grain texture and other kernel characteristics. SDS-PAGE and Western blotting results demonstrated that starch-bound PINA levels of Pina-overexpressing lines were lower than that of Pina-positive control, common wheat cv. Chinese Spring, suggesting a weak association of PINA protein with starch granules in the absence of Pinb. Grain hardness analysis and flour milling tests indicated that the overexpression of PINA resulted in decreased grain hardness and increased flour yield in transgenic durum wheat lines. The agronomic performance of the transgenic and control lines was also examined and it was found that no significant differences in measured traits were observed between Pina-overexpressing and control lines in the 2-year field trials. Since grain hardness strongly affects milling and end-use qualities, the development of medium-hard-textured durum wheat lines is not only of significance for our knowledge of grain hardness and Puroindolines, but also has practical implications for plant breeders and food technologists for the expansion of utilization of durum wheat. [ABSTRACT FROM AUTHOR]

Grain texture is an important trait in wheat quality, and is related to the presence or absence of puroindolines a and b. In barley, these proteins are synthesised by the Hordoindoline ( Hin) genes, orthologs of the Puroindoline ( Pin) genes present in bread wheat and Aegilops species. In this study, the variation of Hin genes has been characterized in two representative lines of Hordeum chilense Roem. et Schult., a wild barley species that has been used in the development of a new man-made cereal (tritordeum, × Tritordeum Ascherson et Graebner). Two novel alleles were detected in this material, one for the Hina- H 1 gene and another for the Hinb- H 1 gene. These alleles demonstrated high similarity to the Pin genes of bread wheat, which may explain the soft grain texture of tritordeum. This suggests that the variation present in H. chilense could be utilized in wheat breeding through the use of tritordeum as a bridge species, to extend the range of different textures. [ABSTRACT FROM AUTHOR]

It is shown that the rate of the genotype's impact in the total impact of all other factors dictating the rate and variability of characteristics depending on the population varies with respect to the grain weight per area unit from 18.3 to 37.6%, the total grain hardness from 9.6 to 27.2%, the content of gluten in flour from 8.8 to 23.7%, and the IDK-1 (Gluten Deformation Gauge) rate from 8.5 to 48.1%. [ABSTRACT FROM AUTHOR]

Grain hardness is one of the most important characteristics of wheat quality. Soft endosperm is associated with the presence of two proteins in the wild form, puroindoline a and b. The puroindoline genes and their derived proteins are present in the putative wheat diploid ancestors which are thought to be the donors of the A, B and D genomes in common and durum wheat. In this study, we investigated the variability of grain hardness in einkorn, along with the nucleotide diversity of Pina and Pinb genes in a collection of einkorn wheat and T. urartu, in addition to studying the neutrality and linkage disequilibrium of these genes. Various alleles were detected for Pina and Pinb genes including three novel alleles for the Pinb locus: Pinb- A 1i, Pinb- A 1j and Pinb- A 1k. Some differences were found in grain hardness between the different genotypes. The neutrality test showed a different pattern of variation between the two Pin genes. The genetic analysis of a diploid wheat collection has demonstrated that these species are a potential source of novel puroindoline variants. Our data suggest that, although further studies must be carried out, these variants could be used to expand the range of grain texture in durum and common wheat, which would permit the development of new materials adapted to novel uses in the baking and pasta industry. [ABSTRACT FROM AUTHOR]

Grain hardness of wheat is determined by the hardness ( Ha)-locus region, which contains three friabilin-related genes: puroindoline-a ( Pina), puroindoline-b ( Pinb) and GSP- 1. In our previous study, we produced the transgenic rice plants harboring the large genomic fragment of the Ha-locus region of Aegilops tauschii containing Pina and GSP- 1 genes by Agrobacterium-mediated transformation. To examine the effects of the transgenes in the rice endosperms, we firstly confirmed the homozygosity of the T-DNAs in four independent T lines by using fluorescence in situ hybridization (FISH) and DNA gel blot analyses. The transgenes, Pina and GSP- 1, were stably expressed in endosperms of the T and T seeds at RNA and protein levels, indicating that the promoters and other regulatory elements on the wheat Ha-locus region function in rice, and that multigene transformation using a large genomic fragment is a useful strategy. The functional contribution of the transgene-derived friabilins to the rice endosperm structure was considered as an increase of spaces between compound starch granules, resulting in a high proportion of white turbidity seeds. [ABSTRACT FROM AUTHOR]

The endosperm structure of the wheat kernel determines its end-use quality. The known diversity in endosperm structure is related to the Pina- D1 and Pinb- D1 genes comprising the Ha locus on chromosome 5DS. We studied the effect of a gene introduced into bread wheat from the diploid relative, Aegilops speltoides, a putative donor of the B genome. Grain hardness and vitreousness were investigated in lines with homoeologous introgressions into chromosome 5A of spring wheat cultivar ‘Rodina’. One introgression changed the endosperm texture from hard to soft and had the same effect when transferred to other wheat genotypes. This indicated that its action was analogous to the dominant allele at the Ha locus. The temporary symbol Ha– Sp is given to the gene. Segregation for vitreousness in F offspring from monosomic hybrids was also investigated. Genetic variability for endosperm structure in wheat may be extended by manipulating both hardness and vitreousness. Wheat germplasm with introgressions from wild relatives can increase the genetic variability of milling characteristics. [ABSTRACT FROM AUTHOR]

Grain hardness plays an important role in determining both milling performance and quality of the end-use products produced from common or bread wheat. The objective of this study was to characterize allelic variations at the Pina and Pinb loci in Xinjiang wheat germplasm for further understanding the mechanisms involved in endosperm texture formation, and the status of grain texture in Chinese bread wheat. A total of 291 wheat cultivars, including 56 landraces, and 95 introduced and 140 locally improved cultivars, grown in Xinjiang, were used for SKCS measurement and molecular characterization. Among the harvested grain samples, 185 (63.6%), 40 (13.7%), and 66 (22.7%) were classified as hard, mixed and soft, respectively. Eight different genotypes for the Pina and Pinb loci were identified, including seven previously reported genotypes, viz., Pina-D1a/ Pinb-D1a, Pina-D1a/ Pinb-D1b, Pina-D1b/ Pinb-D1a, Pina-D1a/ Pinb-D1p, Pina-D1a/ Pinb-D1q, Pina-D1a/ Pinb-D1aa, Pina-D1a/ Pinb-D1ab, and a novel Pinb allele, Pinb-D1ac. This new allele, detected in Kashibaipi (local landrace) and Red Star (from Russia) has a double mutation at the 257th (G to A substitution) and 382nd (C to T substitution) nucleotide positions of the coding region. Pina-D1b, Pinb-D1b, and Pinb-D1p were the most common alleles in Xinjiang wheat germplasm, with frequencies of 14.3%, 38.1% and 28.6% in hard textured landraces, 25.5%, 56.9% and 11.8% in hard introduced cultivars, and 24.8%, 47.8% and 26.5% in hard locally improved cultivars, respectively. The restriction enzymes ApaI, SapI, BstXI and SfaNI were used to identify Pinb-D1ab or Pinb-D1ac, Pinb-D1b, Pinb-D1e and Pinb-Dg, respectively, by digesting PCR products of the Pinb gene. The unique grain hardness distribution in Xinjiang bread wheat, as well as the CAPs markers for identification of the Pinb alleles provided useful information for breeding wheat cultivars with optimum grain textures. [ABSTRACT FROM AUTHOR]

Puroindoline genes ( Pina and Pinb) form the molecular basis of wheat grain hardness or texture. Variations in either gene are reported to be associated with grain hardness in wheat. Here, a modified denaturing PAGE was used to detect Pina and Pinb allelic variations in 102 common wheat cultivars and other species related to wheat. Two variations of Pina ( Pina-D1b and Pina-D1p) and five variations of Pinb (null, Pinb-D1b, Pinb-D1u, Pinb-D1v and Pinb-D1w) were identified in common ( T. aestivum) and spelt wheats ( T. aestivum ssp. spelta). No allelic variation was found in Tibet semi-wild wheat ( T. aestivum ssp. tibetanum), club wheat ( T. compactum), or Aegilops tauschii. Puroindoline genes were absent in wild␣emmer ( T. turgidum var. dicoccoides). The sequencing results of the PCR fragments from Pina and Pinb (except for null type) indicated allelic variants carrying single base mutation, such as Pina-D1p, Pinb-D1u, Pinb-D1v and Pinb-D1w were novel types. Our results showed that the modified PAGE used in this study provided a satisfactory resolving power for identifying single nucleotide mutations; therefore, it is a practical and simple tool to study allelic variation of Pina and Pinb in wheat and related species. [ABSTRACT FROM AUTHOR]

Kernel texture is an important characteristic for both the milling and the end-use quality of wheat (Triticum aestivumL.). Gene sequence variation and mutations to the two puroindoline genes (PinaandPinb), located at theHalocus on chromosome 5DS, account for the majority of variation in wheat kernel texture. Other factors also influence kernel texture, including effects associated with different maternal parent backgrounds. To investigate the effect of two hard puroindoline alleles in different maternal backgrounds, a population of 228 recombinant inbred lines (RILs) derived from a reciprocal cross between two wheat cultivars ‘ID377s’ (Pina-D1b/Pinb-D1a) and ‘Klasic’ (Pina-D1a/Pinb-D1b) were examined in two succeeding generations (F7&F8). Kernel texture was determined using the Single Kernel Characterization System (SKCS) and the RIL puroindoline haplotype was identified by the sequence-specific PCR amplification of each gene. Analysis of variance identified a significant (P= 0.001) effect of the maternal parent and puroindoline mutation on kernel texture. RILs containing thePina-D1bmutation were significantly harder than lines containing thePinb-D1bmutation. RILs which had Klasic as the maternal parent were significantly harder than those which had ID377s as the maternal parent. When the maternal parent and puroindoline allele were analyzed in combination, RILs derived from Klasic as the maternal parent and thePina-D1ballele were significantly harder (P= 0.001) than those containing the same allele but ID377s as the maternal parent. The same occurred for RILs containing thePinb-D1ballele, lines with Klasic as the maternal parent were harder than lines with ID377s as the maternal parent. These results corroborate the harder phenotype of thePina-D1ballele and indicate a significant maternally-inherited contribution to kernel texture variation. [ABSTRACT FROM AUTHOR]

Amphiphilic proteomic analysis was carried out on the ITMI (International Triticae Mapping Population) population resulting from a cross between "Synthetic", i.e.: "W7984" and "Opata". Out of a total of 446 spots, 170 were specific to either of the two parents, and 276 were common to both. Preliminary analysis, which was performed on 80 progenies (Amiour et al. 2002a), was completed here using a total of 101 selfed lines. Seventy two Loci of amphiphilic spots placed at LOD = 5 were conclusively assigned to15 chromosomes. Some spots mapped during the first analysis were eliminated because of the significant distortion segregation observed in the second analysis. Group-1 chromosomes had by far the greatest number of mapped spots (51). Using the Quantitative Trait Loci (QTLs) approach, analysis of the quantitative variation of each spot revealed that 96 spots out of the 170 specific ones showed at least one Protein Quantity Locus (PQL). These PQLs were distributed throughout the genome. With Matrix Laser Desorption Ionisation Time Of Flight (MALDI-TOF) spectrometry and Database interrogation, a total of 93 specific and 41 common spots were identified. This enabled us to show that the majority of these proteins are associated with membranes and/or play a role in plant defence against external invasions. Using multiple-regression analysis, other amphiphilic proteins, in addition to puroindolines, were shown to be involved in variation in kernel hardness in the ITMI population. [ABSTRACT FROM AUTHOR]

Seeds from near-isogenic hard and soft wheat lines were harvested at regular intervals from 5 days post-anthesis to maturity and examined for hardness using the single kernel characterisation system (SKCS). SKCS analysis revealed that hard and soft lines could be distinguished from 15 days post-anthesis (dpa). This trend continued until maturity where the difference between the hard and soft lines was most marked. SKCS could not be applied to the small 5- and 10-dpa wheat kernels. Fresh developing endosperm material was examined using light microscopy and no visible differences between the cultivars were detected. When air-dried material was examined using scanning electron microscopy (SEM) differences between soft and hard lines were visible from as early as 5 dpa. Accumulation of puroindoline a and puroindoline b was investigated in developing seeds using both Western blotting and ELISA. Low levels of puroindoline a could be detected in the soft cultivar from 10 dpa, reaching a maximum at 32 dpa. In the hard cultivar, puroindoline a levels were negligible throughout grain development. Puroindoline b accumulates in both the soft and hard cultivars from 15 dpa, but overall contents were higher in the soft cultivar. These findings indicate that endosperm hardness is expressed very early in developing grain when few starch granules and storage proteins were deposited in the endosperm cells. Further, the near-isogenic soft and hard Heron lines could be differentiated by SEM at a stage in development when the accumulation of puroindolines could not be detected by the methods used in this study. [ABSTRACT FROM AUTHOR]

Wheat grain hardness is a major factor in the wheat end-product quality. Grain hardness in wheat affects such parameters as milling yield, starch damage and baking properties. A single locus determines whether wheat is hard or soft textured. This locus, termed Hardness (Ha), resides on the short arm of chromosome 5D. Sequence alterations in the tryptophan-rich proteins puroindoline a and b (PINA and PINB) are inseparably linked to hard textured grain, but their role in endosperm texture has been controversial. Here, we show that the pinB-D1b alteration, common in hard textured wheats, can be complemented by the expression of wild-type pinB-D1a in transformed plants. Transgenic wheat seeds expressing wild-type pinB were soft in phenotype, having greatly increased friabilin levels, and greatly decreased kernel hardness and damaged starch. These results indicate that the pinB-D1b alteration is most likely the causative Ha mutation in the majority of hard wheats. [ABSTRACT FROM AUTHOR]

The variation in grain hardness is the single most important trait that determines end-use quality of wheat. Grain texture classification is based primarily on either the resistance of kernels to crushing or the particle size distribution of ground grain or flour. Recently, the molecular genetic basis of grain hardness has become known, and it is the focus of this review. The puroindoline proteins a and b form the molecular basis of wheat grain hardness or texture. When both puroindolines are in their `functional' wild state, grain texture is soft. When either one of the puroindolines is absent or altered by mutation, then the result is hard texture. In the case of durum wheat which lacks puroindolines, the texture is very hard. Puroindolines represent the molecular-genetic basis of the Hardness locus on chromosome 5DS and the soft ( Ha) and hard ( ha) alleles present in hexaploid bread wheat varieties. To date, seven discrete hardness alleles have been described for wheat. All involve puroindoline a or b and have been designated Pina-D1b and Pinb-D1b through Pinb-D1g. A direct role of a related protein, grain softness protein (as currently defined), in wheat grain texture has yet to be demonstrated. [ABSTRACT FROM AUTHOR]

Barley (Hordeum vulgare L.) cultivars vary in traits such as grain hardness and malt quality. However, little is known about the genetic basis of these grain quality traits in barley, while more is known about the basis of grain hardness in wheat (Triticum aestivum L.). Puroindolines are endosperm-specific proteins found in wheat and barley, as well as other members of the Triticeae. In wheat, variation of puroindoline sequence is associated with most of the variability in wheat grain texture. However, no information exists on sequence variation of the barley homologs of puroindolines, the hordoindolines. We have therefore chosen to isolate and characterize the hordoindoline (hin) sequences of eight North American barley cultivars. The barley sequences contain numerous non-conservative amino-acid substitutions relative to their wheat counterparts. However, no significant rearrangements were found in either hinA or hinB of barley. Three hinA and two hinB sequence types were found among the eight barley cultivars examined, indicating substantial allelic variation at this locus. The hinB sequence variability was used to map hinB to the short arm of chromosome 5H in a Steptoe/Morex mapping population, which is coincident with the previously mapped location of hinA and Gsp (grain-softness protein). This chromosomal location also coincides with a small barley malt-extract QTL, suggesting that hordoindoline sequence variation may play a small role in barley grain quality. Efforts to correlate barley seed textural differences and malting quality with hordoindoline sequence type are ongoing. [ABSTRACT FROM AUTHOR]

Twenty-two sorghum genotypes were evaluated for grain mould response, 13 morphological and biochemical traits thought to contribute to resistance, and 3 agronomic traits related to utilization. Measurements of grain mould (field grade score, threshed grade score, ergosterol content, and percentage germination) were strongly correlated with one another. Highly significant correlations between measures of grain mould and seed hardness, seed phenol content in acid methanol extract, and glume colour indicated that they strongly affected grain mould response. Harder grain, higher levels of seed phenols, and darker glumes contributed to grain mould resistance. Weaker and less consistent correlations between measures of grain mould and seed colour, seed flavan-4-ol content, glume phenol and flavan-4-ol contents, and glume cover indicated relatively less effect of these traits on grain mould response. Genotype means indicated that combinations of several traits are required to achieve resistance. Germplasm lines, including coloured-seeded lines IS 14375, IS 14387, IS 18144, and IS 18528, and white-seeded lines IS 21443, IS 24495 and IS 25017, showed greatest grain mould resistance. Improved lines generally had poorer grain mould resistance than these landraces. However, the best improved lines were comparable in resistance to white-seeded landraces. B58586, IS 14375 and IS 14387 are hard-seeded guinea sorghum lines that can be used as sources of grain mould resistance for West Africa. SP 33316, SP 33349 and GM 15018 are agronomically elite lines that can be used as sources of grain mould resistance for further improvement of white-seeded sorghum for South Asia and other regions. [ABSTRACT FROM AUTHOR]

Serpins ( Serine proteinase inhibitors) are the family of proteins involved in the inhibition of proteinases from endogenous and other sources and thus have role in disease and pest resistance. In addition, serpins have the properties influencing grain quality traits. The genes coding for serpin proteins are present on the long arm of the 5B chromosome. In the present investigation, allelic variations in the serpin genes encoded by Srp5Bb were assessed using CAP-PCR among the 300 wheat varieties developed in India during the last 100 years. Eighty percent of the varieties exhibited wild type ( Srp5Ba) and 20% mutated (Srp5Bb) form of the allele. Moreover, the frequency of Srp5Bb allele decreased among the recently released varieties as compared to older varieties. Only six out of 50 varieties used as checks in national trials showed the presence of Srp5Bb allele. There was no relationship between Srp5B allelic types and grain hardness. The information is useful to further investigate the role of Srp5B alleles in disease resistance and imparting grain quality. [ABSTRACT FROM AUTHOR]

Grain hardness (texture) in barley is a commercially important trait, associated with water-uptake during the steeping phase of malting, quantified by measuring endosperm hardness. Hordoindolines are seed proteins of barley, related to the wheat puroindoline proteins. The Hordoindoline genes Hina, Hinb-1 and Hinb-2 are orthologs of wheat Pin genes. The information on contributions of Hin genes to barley grain hardness is limited and somewhat ambiguous. Hence this study aimed to investigate the genetic diversity of Hin genes in 12 Australian barley cultivars and 14 landraces originating from geographic centers of diversity. The grain hardness was determined by the Single Kernel Characterisation System (SKCS) and ranged between 24.2–78.5 SKCS units for cultivars and 48.7–94.4 SKCS units for landraces. Hin gene amplifications and DNA sequencing indicated notable genetic diversity, with seven Hina, six Hinb-1 alleles and eight Hinb-2 alleles detected. Some of the SNPs led to substitutions at the potentially functionally important tryptophan rich domain and certain basic and hydrophobic residues in the putative proteins. A novel Hinb-1 allele with an insertion at nucleotide position 210, leading to a frame-shift mutation, was discovered in landrace L400211 from Ethiopia that had a high SKCS hardness value, indicating harder grain. The study suggests that Hin gene variations may contribute to barley grain hardness, and selection of certain alleles may be useful for breeding for varying barley grain textures. [ABSTRACT FROM AUTHOR]