A technique for determining the ergosterol content in mycorrhizal pine roots using HPLC was developed. Pure cultures of different mycorrhizal fungi contained very similar and constant amounts of ergosterol, and calculations of fungal biomass in mycorrhizal roots based on ergosterol readings agreed well with results using other methods. The extraction and sample purification were simple and reliable. Consequently, the technique is considered practical wherever accurate estimates of the intensity of mycorrhizal infection are required.

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The quality of wheat depends on a large complex of genes and environmental factors. The objective of this study was to identify quantitative trait loci controlling technological quality traits and their stability across environments, and to assess the impact of interaction between alleles at loci Glu-1 and Glu-3 on grain quality. DH lines were evaluated in field experiments over a period of 4 years, and genotyped using simple sequence repeat markers. Lines were analysed for grain yield (GY), thousand grain weight (TGW), protein content (PC), starch content (SC), wet gluten content (WG), Zeleny sedimentation value (ZS), alveograph parameter W (APW), hectolitre weight (HW), and grain hardness (GH). A number of QTLs for these traits were identified in all chromosome groups. The Glu-D1 locus influenced TGW, PC, SC, WG, ZS, APW, GH, while locus Glu-B1 affected only PC, ZS, and WG. Most important marker-trait associations were found on chromosomes 1D and 5D. Significant effects of interaction between Glu-1 and Glu-3 loci on technological properties were recorded, and in all types of this interaction positive effects of Glu-D1 locus on grain quality were observed, whereas effects of Glu-B1 locus depended on alleles at Glu-3 loci. Effects of Glu-A3 and Glu-D3 loci per se were not significant, while their interaction with alleles present at other loci encoding HMW and LMW were important. These results indicate that selection of wheat genotypes with predicted good bread-making properties should be based on the allelic composition both in Glu-1 and Glu-3 loci, and confirm the predominant effect of Glu-D1d allele on technological properties of wheat grains.Electronic supplementary materialThe online version of this article (doi:10.1007/s13353-016-0362-5) contains supplementary material, which is available to authorized users.

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The influence of grain hardness, determined by using molecular markers and physical methods (near-infrared (NIR) technique and particle size index—PSI) on dough characteristics, which in turn were determined with the use of a farinograph and reomixer, as well as bread-making properties were studied. The material covered 24 winter wheat genotypes differing in grain hardness. The field experiment was conducted at standard and increased levels of nitrogen fertilization. Results of molecular analyses were in agreement with those obtained by the use of physical methods for soft-grained lines. Some lines classified as hard (by physical methods) appeared to have the wild-type Pina and Pinb alleles, similar to soft lines. Differences in dough and bread-making properties between lines classified as hard and soft on the basis of molecular data appeared to be of less significance than the differences between lines classified as hard and soft on the basis of physical analyses of grain texture. Values of relative grain hardness at the increased nitrogen fertilization level were significantly higher. At both fertilization levels the NIR parameter determining grain hardness was significantly positively correlated with the wet gluten and sedimentation values, with most of the rheological parameters and bread yield. Values of this parameter correlated with quality characteristics in a higher degree than values of particle size index.

An improved method for separating and characterizing high molecular weight glutenin subunits (HMW-GS) in hexaploid triticale by capillary zone electrophoresis (CZE) was developed. A low-concentrate mixture of hydrophilic polymers, poly(vinylpyrrolidone) (PVP) and hydroxypropylmethylcellulose (HPMC), in an isoelectric buffer was employed for dynamic coating of the capillary inner wall. In separation buffer PVP with lower concentrated poly(ethylene oxide) (PEO) was replaced. The CZE electropherograms of HMW-GS showed two group peaks in accordance with x- and y-type subunits with migration times of 6.8-7.8 and 8.4-11.5 min, respectively. In total, 14 HMW subunits (2 subunits encoded by Glu-A1 locus and 12 by Glu-B1) were identified. The CZE analyses revealed that each of the subunits Bx7 and By8 determined by SDS-PAGE makes up three subunits (Bx6.8, Bx7, and Bx7* and By8, By8*, and new By8**, respectively), with different migration times. It was also shown that the subunits By18 and By20 in triticale determined by SDS-PAGE have different migration times in comparison with the same subunits in bread wheat. For these new HMW-GS, the following names were assigned: By18* instead of By18 and By20* instead of By20. The presented CZE method is an efficient alternative to the SDS-PAGE procedure for early selection of useful triticale genotypes with good breadmaking quality.

Molecular markers were used to identify the allele/gene composition of complex loci Glu-A1 and Glu-B1 of high-molecular-weight (HMW) glutenin subunits in triticale cultivars. Forty-six Polish cultivars of both winter and spring triticale were analysed with 7 PCR-based markers. Amplified DNA fragments of HMW glutenin Glu-1 genes were separated by agarose slab-gel electrophoresis. Differences between all 3 alleles at the locus Glu-A1 [Glu-A1a (encoding Ax1), 1b (Ax2*), and 1c (AxNull)], 4 alleles at Glu-B1-1 [Glu-B1-1a (Bx7), 1b (Bx7*), 1d (Bx6), 1ac (Bx6.8)], and 5 alleles at Glu-B1-2 [Glu-B1-2a (By8), 2b (By9), 2o (By8*), 2s (By18*), and 2z (By20*)] were revealed. In total, 16 allele combinations were observed. Molecular markers are particularly helpful in distinguishing the wheat Glu-A1a and Glu-A1b alleles from the rye Glu-R1a and Glu-R1b alleles in triticale genotypes, respectively, as well as subunits Bx7 from Bx7* and By8 from By8*, which could not be distinguished by SDS-PAGE. Novel glutenin subunits By18* and By20* (unique to triticale) were identified. HMW glutenin subunit combinations of Polish triticale cultivars, earlier identified by SDS-PAGE analyses, were verified by PCR-based DNA markers. Rapid identification of wheat Glu-1 alleles by molecular markers can be an efficient alternative to the standard separation procedure for early selection of useful triticale genotypes with good bread-making quality.

A rapid and reliable method for separation and characterization of the variability of high-molecular-weight secalin subunits (HMW-SS) in hexaploid triticale (x Triticosecale Wittmack) by CZE has been developed. In this method, a mixture of two poly(ethylene oxide) polymers differing in molecular weight and a high concentration of ACN in isoelectric buffer was applied as the running electrolyte. For dynamic coating of the capillary inner wall, a low-concentration mixture of poly(vinylpyrrolidone) and hydroxypropylmethylcellulose was employed. Wide allelic variations in rye HMW-SS composition, including some novel x- and y-type HMW-SS, were detected by CZE. The CZE electropherograms of HMW-SS showed two groups of peaks in accordance with y- and x-type subunits, with migration times of 8.0-8.8 and 11.0-13.3 min, respectively. HMW-SS differed in migration times from the simultaneously resolved HMW glutenin subunits, but frequently had very similar electrophoretic mobilities during separation by SDS-PAGE. Each of the two rye subunits 2r and 6.5r detected by SDS-PAGE represents in fact two subunits (5.1r or 5.2r, and 6.4r or 6.5r, respectively). After analyzing 106 European triticale cultivars, 12 HMW-SS were identified (six x-type and six y-type). They form six allelic variants of these subunits. The simultaneous separation and identification of triticale HMW glutenin and secalin subunits by CZE is an efficient alternative to SDS-PAGE and should facilitate breeding of valuable cultivars.