Pre-harvest sprouting resistance and haplotype variation of ThVp-1 gene in the collection of wheat-wheatgrass hybrids.

The germplasm collection of 87 wheat-wheatgrass hybrids developed in Tsitisin Main Botanical Garden (Russia, Moscow) was evaluated for resistance to pre-harvest sprouting (PHS) by spike sprouting (SS) and germination index (GI) assays as well as for spike and grain features. The PHS resistance variation and haplotype polymorphism of the wheatgrass ThVp-1 and wheat TaVp-1B genes orthologues of Vp-1 was revealed in the studied collection. Four haplotypes of ThVp-1 were revealed: ThVp-1a (41% of the entries), ThVp-1b (13%), ThVp-1c (29%), and ThVp-1d (15%). The association between the allelic state of ThVp-1 and PHS resistance in the wheat-wheatgrass hybrids was shown: haplotype ThVp-1d of the wheatgrass Vp-1 gene is significantly associated with reduced PHS in the wheat-wheatgrass hybrids (mean SS 0.33, mean GI 0.64). The resistant entries may be perspective as a source of PHS resistance in the development of commercial cultivars of perennial wheat

qPCR as a Selective Tool for Cytogenetics

qPCR is widely used in quantitative studies of plant genomes and transcriptomes. In this article, this method is considered as an auxiliary step in the preparation and selection of markers for FISH analysis. Several cases from the authors’ research on populations of the same species were reviewed, and a comparison of the closely related species, as well as the adaptation of the markers, based on satellite tandem repeats (TRs) using quantitative qPCR data was conducted. In the selected cases, TRs with contrast abundance were identified in the cases of the Dasypyrum, Thinopyrum and Aegilops species, and the transfer of TRs between the wheat and related species was demonstrated. TRs with intraspecific copy number variation were revealed in Thinopyrum ponticum and wheat-wheatgrass partial amphidiploids, and the TR showing predominant hybridization to the sea buckthorn Y chromosome was identified. Additionally, problems such as the absence of a reference gene for qPCR, and low-efficiency and self-complementary primers, were illustrated. In the cases considered here, the qPCR results clearly show high correlation with the subsequent results of the FISH analysis, which confirms the value of this method for cytogenetic studies

Association between <i>TaVp-1B</i> alleles (of wheat origin) and SS values in the wheat-wheatgrass hybrid collection.

<p>Association between <i>TaVp-1B</i> alleles (of wheat origin) and SS values in the wheat-wheatgrass hybrid collection.</p

Electrophoresis of the CAPS-marker Vp1BB4_<i>Hae</i>III fragments.

<p>The ~600 bp (arrow) and ~550 bp (*) are diagnostic fragments for the wheatgrass <i>ThVp1</i> gene. M—size standard (100 bp DNA Ladder), 1 –<i>Triticum aestivum cv</i>. <i>Nota</i>, 2–90, 3–150 k., 4–168, 5 –<i>Th</i>. <i>intermedium</i> PI 401200.</p

Classification of wheat-wheatgrass entries by germination index (GI).

<p>Classification of wheat-wheatgrass entries by germination index (GI).</p

Association between <i>TaVp-1B</i> alleles (of wheat origin) and GI values in the wheat-wheatgrass hybrid collection.

<p>Association between <i>TaVp-1B</i> alleles (of wheat origin) and GI values in the wheat-wheatgrass hybrid collection.</p

The combined results of application of the Vp1BB4_<i>Hae</i>III and Vivip markers in the wheat-wheatgrass hybrids.

<p>The combined results of application of the Vp1BB4_<i>Hae</i>III and Vivip markers in the wheat-wheatgrass hybrids.</p

Classification of entries based on the results of germination index (GI) and spike sprouting (SS) assays.

<p>Classification of entries based on the results of germination index (GI) and spike sprouting (SS) assays.</p

Association between <i>ThVp-1</i> haplotypes and GI values in the wheat-wheatgrass hybrid collection.

<p>Association between <i>ThVp-1</i> haplotypes and GI values in the wheat-wheatgrass hybrid collection.</p