Response of wheat plants with different allele status of gene Gpc-B1 on zinc deficiency

The problem of improving the wheat grain quality is currently relevant all over the world, and as a result, a search for methods is being carried out to eliminate it. It is proposed to use the method of distant hybridization for this purpose, but there are few experimental data confirming this possibility. But it is known that with the introduction of a functional Gpc-B1 allele from wild wheat (Triticum dicoccoides) into varieties of common wheat (T.aestivum), the protein and some micronutrients content, including zinc, increases in the grain. It is believed that this effect is associated with the participation of Gpc-B1 in more efficient zinc remobilization in the plant. Therefore, it can be assumed that plants with a functional Gpc-B1 allele will be more resistant to zinc deficiency. However, there is practically no such data. We studied the effect of zinc deficiency on the flag leaf area, chlorophylls content in it, spike size and grains number in wheat plants that differ in the allele status of gene Gpc-B1. The objects were T.dicoccoides (functional allele – f.a.), T.aestivum cv.Festivalnaya (non-functional allele – n-f.a.), and two lines isolated in the offspring from crossing cv.Festivalnaya with T.dicoccoides: line 15-7-1 (f.a.) and line 15-7-2 (n-f.a.). The plants were grown in pots with sand. Control plants grew at the optimum zinc concentration; in the experimental variants, zinc was not added to the substrate.

The studies carried out revealed a inhibitory effect of zinc deficiency on the flag leaf growth of only line 15-7-2. In cv.Festivalnaya plants no significant differences from the control were observed. In contrast, in T.dicoccoides and line 15-7-1, the flag leaf area was higher than the control. In addition, in these plants under zinc deficiency, a high chlorophylls content remained, while in plants with a n-f.a., it significantly decreased. It was also found that in line 15-7-2 under zinc deficiency the spike length and the number of formed grains decreased.

The results show that the presence of a functional Gpc-B1 allele in T.aestivum promotes better plant adaptation to zinc deficiency and the maintenance of high seed productivity. This confirms the promise of using the remote hybridization method to create wheat lines with high grain yields in deficiency of this micronutrient.

The work was supported by RFBR (project No 20-516-00016), BRFBR (project No Б20Р-240) and under state order (No. 0218-2019-0074).