Plant physiology – the science dealing with plant organism functioning – is one of the core fields for two institutes of the Karelian Research Centre RAS. Tatyana Shibaeva, Leading Researcher at the Institute of Biology, Natalia Galibina, Chief Researcher at the Forest Research Institute, and Irina Teslyuk, Junior Researcher at the Forest Research Institute presented their research results at the conference.
Effects of abnormal light-dark cycles on plant growth
Tatiana Shibaeva, Doctor of Biological Sciences, presented the findings of a study on the possibilities of controlling plant growth and development in indoor systems using anomalous light-dark cycles, i.e. with day and night alternation regimes not typical of natural conditions.
Tatyana Shibaeva, Leading Researcher, Institute of Biology KarRC RAS
Scientists at the Institute of Biology KarRC RAS proved that anomalous light-dark cycles can promote plant growth and development. A light/dark cycle is characterized by two factors: the duration (period) of the cycle and the light/dark ratio. A cycle is considered normal if its period equals the usual period of the circadian cycle (24 h); otherwise it is called anomalous (e.g., 8/4 h or 24/12 h). A number of previous studies have shown that anomalous light-dark cycles, including 24h light exposure, can have a positive effect on plants (accelerating growth and development, increasing the accumulation of valuable metabolites, and reducing the content of undesired anti-nutrients, such as nitrates) while reducing energy costs per unit of produce.
The biological nature of this phenomenon has been understudied, although experiments with anomalous light-dark cycles have made it clear that plants encounter a new type of stress – photoperiodic stress.
– There is no such stress under natural conditions, since the regular daily 24-hour cycle always has a single change from day to night. This type of stress has so far been little studied, but it does deserve scrutiny. Importantly, the consequences of stress are not necessarily negative, and the classical stress theory has the concept of eustress – positive, beneficial stress – as opposed to distress – negative, harmful stress, – noted Tatyana Shibaeva.
Molecular controls of wood development
The studies of Natalia Galibina, Doctor of Biological Sciences, focus on the molecular mechanisms regulating tissue formation in the trunk of woody plants. Their understanding can enable effective control of the process of wood formation and development – xylogenesis.
Natalia Galibina, Chief Researcher, Forest Research Institute KarRC RAS
In her talk at the conference, Natalia Galibina presented the role of special proteins – SWEET-family sugar transporters – in regulating the productivity of woody plants. These proteins are known to help transport sucrose and glucose through plant membranes and participate in the distribution of carbon fluxes between photosynthesizing leaves and newly formed wood. Silver birch, including its form Betula pendula var. carelica (curly birch), was chosen as the object.
Scientists of the Forest Research Institute were the first to demonstrate the role of SWEET transporters in the allocation of sugars produced photosynthetically in leaves to the formation of different xylem (wood) tissues, using the case of naturally growing adult plants.
– In other words, SWEET transporters can be considered as indicators of the sugar flux in trunk tissues developing at different stages of xylogenesis – during the active period and at later stages, – emphasized Natalia Galibina.
The results of the study hold promise for the efforts to promote plant productivity and gain wood with desired properties, including the unique grain figure of curly birch. Previously, the scientists conducted a transcriptomic analysis of stem tissues of two birch forms with different wood formation scenarios, which provided new insights into the regulation of this process.
Irina Teslyuk, Doctoral Student, Junior Researcher, Forest Research Institute KarRC RAS
The conference presentation of doctoral student Irina Teslyuk was about Changes in the Redox Status at Key Stages of Somatic Embryogenesis in Picea abies. The study contributes to the development of a method for mass production of unique genotypes of Norway spruce – one of the most important forest tree species in Karelia.
