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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2023

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Abstract

Forest tree breeding must undergo significant revisions to adapt to the evolving challenges posed by climate change. Addressing the shifts in environmental conditions requires a comprehensive multidisciplinary approach that includes theoretical work and practical application. Specifically, there is a need to focus on developing new breeding strategies that are theoretically sound and practically feasible, considering the economic constraints of actual tree breeding programs. We present a novel concept utilizing genetic evaluation of multiple traits in forest stands of successive ages across wide ecological ranges. Incorporating genomics allows for detailed genetic evaluation, making use of high-density SNP markers and sophisticated algorithms like GBLUP for genetic parameter estimates. High-throughput phenotyping is conducted using drone-borne lidar technology to capture tree height and survival data across various forest stands. Assisted migration is considered to strategically position genotypes across predicted environmental climatic gradients, thereby accommodating the dynamic nature of ecological shifts. Mathematical optimization acts as an essential component for logistics, guiding the spatial allocation and timely substitution of genotypes to ensure a continually adaptive breeding program. The concept replaces distinct breeding cycles with continuous evaluation and selection, enhancing the rate of genetic response over time.

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Abstract

Planting healthy seedlings with optimal growth potential is essential for proper growth and survival in forest regeneration. Assessing the seedling quality prior to planting is therefore important. In this Icelandic study, effects of root damage induced with artificial freezing in young Russian larch seedlings were examined using the root growth capacity method (RGC). Frost tolerance of roots varied during the winter, and root growth in undamaged seedlings fluctuated, indicating seasonal variations in growth rhythm. The LT50 value for root frost tolerance was −13.9°C in late January, but already at −10.6°C (LT10) root damages were severe. After one growing season, shoot elongation was significantly lower in seedlings frozen to −9°C, −13.5°C, and −15.5°C by 23%, 54%, and 72%, respectively, compared with undamaged seedlings. Control seedlings and seedlings frozen to −9°C achieved 100% survival after the first growing season. Survival in seedlings frozen to −13.5°C and −15.5°C was 85% and 27%, respectively. After the second growing season, survival decreased in all frost-damaged seedlings. The ongoing mortality demonstrates the long-lasting effects of planting seedlings with damaged root systems, and the fluctuation in root frost tolerance of young Russian larch seedlings during winter emphasises the need for care when seedlings are moved to outdoor storage.

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Abstract

Modern apple growing requires relatively often orchard replacement due to release of superior cultivars or introduction of new growing technologies. Most of intensive apples orchards are established in the same site where apple trees were cultivated for a long period. Continuous cultivation of the same crop causes stress to plants and often leads to abnormal plant development and decreased productivity what is known as apple replant disease (ARD). Due to ban of chemical soil disinfection, other strategies how to overcome ARD must be developed. Rootstock is becoming to be one of the most important factors to solve this problem and one of the targets of new rootstock breeding programs is rootstock resistance or tolerance to ARD. Different origin and genetic background of rootstocks led to suggest that their adaptiveness to replanted soil will be different. EUFRIN (European fruit research institutes network) Apple and pear cultivar and rootstock testing group established replant trials in several European countries where new apple rootstocks from USA, Great Britain, Poland and Russia are tested. Current paper presents results of the trial performed at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry in 2017-2021. On average of all rootstocks apple trees planted in the fresh soil were by 35% more vigorous and gave 71% higher yield. After the evaluation of tree growth and productivity characters rootstocks ‘G.41’ and ‘G.11’ were the most tolerant to ARD. Trees on rootstocks ‘G.935, ‘Cepiland-Pajam®2’ and ‘EM_02’ had significantly lower yields in replant soil, while tree growth was most stunted on ‘62-396-B10®’ and ‘EM_02’.

Abstract

swap is an R-package designed to help interface and work with SWAP4 model. It consists of a variety of functions that assist the user in otherwise tedious and repetitive tasks.