Determining the Participation of Stem and ear Photosynthesis Information of the Crop and its Quality in Wheat

Abstract

The goal was to assess not only the contribution of non-leaf organs to overall plant photosynthesis, but also the composition of produced compounds in caryopses derived from photosynthesis products transported from various chlorophyll-containing wheat organs. During the caryopsis development period of spring wheat plants, photosynthesis of several organs and their contribution to ear caryopsis formation were assessed using ¹⁴CO₂ labelled carbon (Moskovskaya-35). It turned out that inclusion of 14C into amino acids is more than twice as high in photosynthesis of an ear. Among labeled low molecular weight compounds in caryopsis, during a short exposure (2 hours) after photosynthesis, the most of the labeled carbon in the ¹⁴CO₂ was found from the photoassimilates of the flag leaf (70.4%); from the ear (55.8%), and the least - from the stem under the flag (41.5%). The difference in inclusion of 14C into the caryopsis’ total proteins was observed only with a short exposure of the photosynthesizing organ (2 hours). Water-soluble proteins, as products of photosynthesis of the flag leaf, were synthesized for the most in the caryopsis (flag - 73.9%; stem - 46.4% and ear - 44.8%), and in the synthesis of complex proteins, which are soluble in alkali and Triton X-100, most of 14C was from the products of photosynthesis of non-leaf organs (10.5; 21.5; 28.4 and 4.3; 12.5; 13.4), respectively.