An action of exogenous steroidal glycoside on exhibition of inbreeding depression in red beet plants under protected cultivation technology

The protected cultivation technology, through which the various inbred generations with the combination of economic valuable traits and different level of sterility can be produced, is used in order to accelerate the breeding program. However, there is a negative effect of inbreeding depression and self-incompatibility can often occur and cause the loss of valuable breeding forms. The aim of the work was to study the influence of steroidal glycosides capsicoside (SGC) on exhibition of CMS, and morphobiological parameters of 13 inbred generations that were produced from fertile plant and partly sterile plants with level of sterility 10% and 50%. The seeds were soaked for 24 hours in water solution of SGC with concentration 10-3%, and in water control. Then the seeds were dried up and sown in the greenhouse. The stecklings and roots obtained were vernalized at 3-5 Co. Mother plants were grown under 18 hour photoperiod in greenhouse with supplementary lighting. Inbreeding seeds were obtained in individual cloth isolators. It was shown that for all generations the treatment with SGC improved the seed germination (4-8% more), increased the root index and its length (12-24% more), decreased betanin content (22-48% less) in comparison with control. The action of SGC on the other morphological and biochemical traits such as height of leaf rosette, leaf number, plant and root weight, head size, number of generative buds, and nitrate content was defined by the level of sterility of mother plant. The most expressed effect for all traits mentioned was seen in inbreeding generations of sterile plants with high level of sterility. After action effect of seed treatment with SGC on development of seed plants from inbreeding generations, not depending on sterility level of mother plants, showed the positive influence on plant habitus of seed mother plants, decreasing the plant height, but increasing stem number and functional parameters of microgametophyte in fertile plants. This caused the improved seed formation 1.6-2.2 times higher during inbreeding process and increased the portion of plants with high productivity. The SGC had no effect on exhibition of CMS trait. Thus, the SGC is worth using in valuable highly inbreeding forms inclined to self-sterility, in order to enlarge the genetic variation and output of divers generations. However, it should be taken into consideration that the complicated effect on the plant traits can be noticed in inbreeding generation of red beet and may have an effect on the result of selection process at the root stage.