Comparison of Related Wheat Stocks Possesing 1B or T1BL·1RS Schromosomes: Grain and Flour Quality

Abstract

The agronomic advantage of the T1BL. 1RS translocation and the potential importance of chromosome 1BS to end‐use quality of bread wheat (Triticum aestivum L.) warrant a more precise definition of the relationship of T1BL‐1RS to bread wheat quality. This study was conducted to determine the effect of TIBL. 1RS from ‘Aurora’ on grain and flour quality in multiple near‐isoline pairs with varying genetic background, and to examine the genetic variation among random inbred lines selected only for 1B or T1BL 1RS. Two experiments were conducted, each with a different set of genetic materials derived from the same pair of crosses. In one experiment, 25 pairs of F5‐derived near‐isolines homozygous for either 1B or T1BL‐ 1RS were evaluated in at least two environments; in the second experiment, plants homozygous for either 1B or T1BL‐1RS were selected in the F2, and 40 inbred lines per chromosome type in each cross were evaluated in four environments. The near‐isolines showed high isogenecity for all traits based on comparison of duplicate lines within pairs. The translocated chromosome, on the average, increased grain protein concentration and decreased mixogram rating, mlxogram band width, and sedimentation volume in both crosses. Kernel hardness, flour yield, and mixing time either decreased or did not change in the TIBL 1RS isolines depending on the cross. Water absorption did not change. The T1BL‐1RS and 1B isolines showed similar mixograph properties in eight of the 25 pairs. Genetic variance of TIBL IRS random inbred lines was not reduced for those traits where deleterious effects were most notable, e.g., mixing tolerance and sedimentation volume. Hence, the detrimental effect of T1BL‐ 1RS on dough properties might be mitigated, relative to non‐TIBL 1RS genotypes with equivalent pedigree, by rigorous selection of background genotype. Special attention must be given to mixing tolerance and sedimentation.

Genetic diversity of wheat–rye 1BL.1RS translocation lines derived from different wheat and rye sources

“…Basis of genetic diversity among 1BL.1RS translocations Various effects of wheat genetic background and rye sources have been addressed as major factors in inconsistent agronomic performance and end-use quality traits of 1BL.1RS translocations (Singh et al 1998;Villareal et al 1991;Carver and Rayburn 1995;McKendry et al 2001McKendry et al , 1996Kumlay et al 2003;Kim et al 2004Kim et al , 2005. In those studies either near-isogenic lines or recombinant inbred lines were used in trials, in which the residual confounding impact of impure genetic background of wheat could not be separated from the effects of the introgressed rye chromosome arm.…”

“…Sec-1 was identified by acid polyacrylamide gel electrophoresis (A-PAGE, pH 3.2) using the protocol described in Yan et al (2005). Evaluations of grain and flour quality followed procedures described in detail by Carver and Rayburn (1995); Martín et al (2001), and Kumlay et al (2003), with modifications of Yan and Ren (2004). *Disease severities are on an infection type scale of 0-9 (Leath and Heun 1990; Wan et al 2004) where, 0 = immune, no visible symptoms; 1-3 = resistant, increasing from (i) flecks, no necrosis to (ii) necrosis, to (iii) chlorotic areas with slight sporulation; 4-6 = intermediate, chlorotic areas decreasing in amount while mycelium and conidial production increases from slight to moderate; 7-9 = susceptible, increasing amount, size, and density of mycelium and conidia to a fully compatible reaction…”

“…In those studies either controlled near-isogenic lines or recombinant inbred lines were used in trials, in which the confounding impact of impure wheat genetic background could not be separated from the effects of the introgressed rye chromosome arm. Moreover, the 1BL.1RS lines used in those studies were derived from only two primary translocations, which may not be enough to fully evaluate the possible effects of the 1RS arm on agronomic performance or end-use quality (Carver and Rayburn 1995;Kumlay et al 2003;Kim et al 2004).…”

How Arabinoxylans Modify Gluten and Starch Related Wheat Flour Characteristics

“…There is little information on the role of carbohydrate components in the swelling process. CARVER and RAYBURN (1995) reported that starch-gluten interaction infl uences SDS sediment, and according to MAGHIRANG and co-workers (2006) it can possibly be affected by pentosans or damaged starch as well. Therefore, we fi nd it necessary to consider the role of carbohydrate composition in the sedimentation measurements, especially when unusual carbohydrate components, like dietary fi bre compounds, are present in considerable amounts.…”

Genetic and physical mapping of sequence-specific amplified polymorphic (SSAP) markers on the 1RS chromosome arm of rye in a wheat background

“…This chromosome arm carries resistance genes against different rust species and powdery mildew (Lr26, Sr31, Yr9, Pm8) (McIntosh 1988). Moreover, several studies have suggested that it enhances the yield potential of wheat in certain genetic backgrounds (Carver and Rayburn 1995;Moreno-Sevilla et al 1995;Villareal et al 1995Villareal et al , 1998. One major concern about this translocation is its single origin (Schlegel and Korzun 1997), with the consequence being the absence of any allelic variation on this chromosome arm.…”