Influence of photoperiod on morphogenetic processes in near-isogenic lines in PPD genes of soft wheat

Abstract

Aim. Investigation of the effects of contrast photoperiodic conditions and the state of the Ppd genes (dominant or recessive) on growth and morphogenetic reactions in NILs of soft winter wheat Myronivska 808 and Mercia cultivars. Methods. Experiments were carried out in field and vegetation chamber conditions. NILs were cultivated in contrast photoperiodic conditions: control group plants – in the conditions of a long photoperiod of 16 hours (LD), experimental group plants – in a short photoperiod – 9 hours (SD). The stages of organogenesis, the height of apical growth cones, the number of tillers and biomass of the above-ground part of plants were determined. Results. In our studies, we found that all NILs of both cultivars respond to a photoperiod reduction as typical long-day plants, namely: they have a two-stage of organogenesis delay in development, growth processes are inhibited (growth of the apical cone, formation of tillering shoots and accumulation of plant biomass). It was shown that NILs with the genotypes Ppd-A1a and Ppd-D1a are characterized by accelerated development due to inhibition of growth processes. Conclusions. The genes responsible for controlling the development and photoperiodic sensitivity of soft wheat plants also determine the pace of development, growth and morphogenetic reactions of common wheat plants as in LD photoperiod conditions (16 hours), as well as in SD photoperiod conditions (9 hours).
 Keywords: Triticum aestivum L., Ppd genes, photoperiod, stages of organogenesis, shoot apex.