Influence of genetic origin on the erarly development of Scots pine (Pinus sylvestris) seedlings and their interaction with bacteria from the genera Paenibacillus and Pseudomonas

Scots pine (Pinus sylvestris) is one of the most common trees in Northern Europe and its wood is in demand and commercially important. Many pines suffer from the pathogenic fungus Heterobasidion annosum which damages roots and trunk. It is therefore necessary both to select genetically superior, more resistant pine families and to search for novel biotechnological tools that could suppress fungal infection [1]. One of the possibilities would be to use plant-associated bacteria, capable to suppress the development of phytopathogenic fungi [2]. In this context, it is important to test if selected bacterial candidates are themselves not harmful for pines. The bacteria taken for this research were Paenibacillus sp. and Pseudomonas sp. that were originally isolated from the tissue cultures of hybrid aspen. The aim of this study was to investigate the early development and interaction of different Scots pine (Pinus sylvestris) families with Pseudomonas sp. and Paenibacillus sp. bacteria in vitro and ex vitro. Two groups of pine genetic families were investigated: five families were taken from the genetic reserve of potentially resistant pines in Vaišvydava and five were randomly selected families from Jonava plantation. The seeds from these families were surface-disinfected and planted in vitro on the nutrient medium inoculated with either Paenibacillus sp. or Pseudomonas sp. Also, the effect of bacteria on pines during their ex vitro adaptation stage was investigated. The results showed that Pseudomonas sp. had a negative effect on root growth in seven of the ten tested pine families and, in three of them, the shoot growth was also impaired. Paenibacillus sp. only had negative impact on root growth in the pine family No. 2J; however, in another family (No. 12), this bacteria even caused the development of longer shoots. In turn, ex vitro results showed that Pseudomonas sp. had the strongest negative effect on the [...]Gamtos mokslų fakultetasLietuvos agrarinių ir miškų mokslų centrasVytauto Didžiojo universiteta