Influence of genotype and bacterization on growth, development, and soluble carbohydrate content in soybean E-genes isogenic lines

Abstract

Photoperiod, which regulates the duration of vegetative and generative development, and the plant-microorganism interaction, which influences the metabolic status of plant organisms, are important factors in the regulating plant growth and development. The aim of the study was to determine the influence of Glycine max (L.) Merr. genotype and seed pre-bacterization with a virulent and active strain of Bradyrhizobium japonicum 634b on the plant growth and development, and on the soluble carbohydrate content in leaves of isogenic by E-genes lines under field conditions. Nearly isogenic lines (NILs) of soybean, in which the E1, E2, and E3 genes are located at different allelic loci, were used. Sterile seeds were pretreated with distilled water (control) and Bradyrhizobium japonicum 634b cell suspension (experiment). Plants were grown under natural long-day conditions (16 hours). The growth and development of the soybean were evaluated by phenological observations, morphometric indicators fixed at the V3 and V5 developmental stages, relative growth rate (RGR), and the content of soluble sugars ‒ mono- and oligosaccharides. The effect of the factors studied (genotype, bacterization, and their interaction) was calculated. The results of the experiment and the calculation of the effect of the factor showed that the isoline genotype has the greatest effect on seed germination, phenological development of the plant and duration of the VE-R1 phase, growth of the root system in the V3 and V5 phases, and the content of monosaccharides involved in forming the plant-microorganism interaction. The effect of bacterization is most evident in the RGR, shoot development, and the oligosaccharide content of the leaves of NILs in the V3 and V5 phases. Among the isolines studied, L 80-5879, which has the E1 gene (flowering repressor) in a dominant state, was characterized by minimal sensitivity to bacterization. It was found that bacterization and genotype interaction didn't influence the VE-R1 duration stage and the shoot and root length. The results obtained therefore prove that the E-series genes, which determine the photoperiodic sensitivity of soya beans, can also be indirectly involved in establishing plant-microorganism interactions.

Influence of Bradyrhizobium japonicum on the growth parameters and formation of the assimilation apparatus in E-gene isogenic lines of soybean

“…This discrepancy can be explained by different carbohydrate distributions. Our earlier findings (Hlushach et al, 2023) demonstrated a reduction in the transport form of carbohydrates in leaves under bacterial treatment in both V3 and V5 phases, suggesting a flow of assimilates to the attracting centers -symbiotic nodules and meristems. Furthermore, over the V3-V5 developmental period, the control variant shows a decrease in specific leaf area, while under bacterial treatment, an increase is observed.…”

“…Therefore, under bacterial treatment, there is a very slow biomass accumulation during the V3-V5 development period. Earlier studies on the L63-3117 line identified a decrease in the quantity of oligosaccharides under interaction with B. japonicum (Kirchner) 634b during the V3 and V5 developmental phases (Hlushach et al, 2023). It is worth noting that in the V3 developmental phase under bacterial treatment, the line showed the highest content of chlorophyll a and b.…”