Diversity of Ophiostomatales species associated with conifer-infesting beetles in the Western Carpathians

Bark beetles (Coleoptera: Curculionidae, Scolytinae) are commonly recognised as important agents of tree mortality in coniferous forests of the Western Carpathians. They, together with weevils, are consistently associated with ophiostomatoid fungi. Information regarding conifer beetle-associated fungi in the Western Carpathians remains incomplete and unreliable, particularly with respect to fir-infesting bark beetles. This study aims to clarify associations between fungi in the genera Graphilbum, Leptographium, Ophiostoma and Sporothrix (Ophiostomatales) and their beetle vectors in Norway spruce (Picea abies), European larch (Larix decidua) and silver fir (Abies alba). Samples associated with 20 bark beetle species and weevils were collected from nine stands in Poland and the Czech Republic. Fungi were isolated from adult beetles and galleries. Isolates were identified based on morphology, DNA sequence comparisons for four gene regions (ITS, LSU, ß-tubulin, TEF 1-α) and phylogenetic analyses. In total, 46 distinct taxa were identified, including 25 known and 21 currently unknown species. Several associations between fungi and subcortical insects were recorded for the first time. In addition, O. borealis and O. quercus were detected from A. alba for the first time. The composition of the fungal communities varied among the studied tree species and to a lesser degree among the beetle species. The spruce-infesting bark beetles were commonly associated with species of Leptographium s. l. and Ophiostoma s. str.; the larch-infesting bark beetles were often associated with Ophiostoma s. str. and Sporothrix, while the fir-infesting bark beetles were commonly associated with Ophiostoma s. str. and Graphilbum. The most commonly encountered fungal associates of the examined insects were (a) Grosmannia cucullata, G. piceiperda, Grosmannia sp. 1, Ophiostoma macroclavatum and O. piceae with the spruce-infesting bark beetles; (b) O. pseudocatenulatum and Sporothrix sp. 1 with the larch-infesting bark beetles; and (c) O. piceae, Ophiostoma sp. 2 and Graphilbum sp. 2 with the fir-infesting bark beetles. The differences in fungal associates among the bark beetle species occurring on P. abies, L. decidua and A. alba could be linked to the different habitats that these beetles occupy.     

Quantitative and qualitative analysis of alkaloids composition in the seeds of a white lupin (<Emphasis Type="Italic">Lupinus albus</Emphasis> L.) collection

White lupin (Lupinus albus L.) has unexploited potential as a crop plant due to its high seed yield as well as protein and oil content in seeds. Well-characterized collections of gene resources are very important for breeding as a source of genetic variation. This paper presents the results of analyses for total content and qualitative composition of alkaloids in seeds of 367 L. albus accessions from the Polish Genebank. Accessions were divided into four classes of origin: wild collected material, land races, breeding lines, and cultivars. Apart from the expected broad variation as well as strong differentiation in the alkaloid content, a clear influence of domestication was observed. This was shown as an apparent decrease in the alkaloid content in breeding lines and cultivars classes. The total alkaloid content varies from 0.02 to 12.73% of the seed dry weight. Six major alkaloids (abundance >1%) were revealed: lupanine (28.22–94.49%, mean 76.06% in total content), 13-hydroxylupanine (0.10–32.78%, mean 8.23%), multiflorine (0.00–21.67%, mean 5.52%), albine (0.00–18.55%, mean 4.48%), angustifoline (0.24–12.14%, mean 2.07%), 11,12-seco-12,13-didehydromultiflorine (0.00–12.28%, mean 1.74%). Owing to its abundance, lupanine was found to be the most closely correlated to the total alkaloid content.     

Raffinose family oligosaccharides in seeds of <Emphasis Type="Italic">Pisum</Emphasis> wild taxa,type lines for seed genes,domesticated and advanced breeding materials

The content of raffinose family oligosaccharides (RFOs) in pea seeds constrains their usage in feeding humans and animals. In our research, the content of soluble carbohydrates—particularly α-d-galactosides of sucrose (RFOs)—was analyzed. The materials were as follows: 248 accessions from the Polish Pisum Genebank including representatives of taxa (from species to convarietas), type lines for genes controlling seed characters, and breeding materials and cultivars. Accessions were divided into homogeneous groups considering content of total soluble carbohydrates, total RFOs and individual RFOs: raffinose, stachyose and verbascose. The highest content of total soluble carbohydrates and total RFOs were stated for accessions with wrinkled seeds (r and rb genes) and the lowest content for seeds of the wild species P. fulvum Sibth. et Sm. Accessions valuable for breeding (for further decreasing of anti-nutritional compounds) were found among domesticated taxa (P. sativum subsp. sativum convar. vulgare Alef. and speciosum (Dierb.) Alef.), breeding lines, and some wild taxa. Accessions with decreased content of a total RFOs and verbascose are particularly valuable. It was found that the content of total RFOs was the most highly, frequently, and positively correlated with a stachyose and verbascose content. However, in P. fulvum seeds with the lowest content of RFOs and verbascose, a high correlation between the content of total RFOs and stachyose was revealed. Contents of all oligosaccharides were substantially lower in lines with dominant alleles of main pea seed genes (R, A, and I). It can be assumed that wild, primitive peas were characterized by not-all-to-high (rather not high) content of oligosaccharides; then recessive mutations in mentioned genes resulted in an increased content of RFOs. It seems to be an interesting observation from an evolutionary point of view.     

Nitrogen leaching from tile-drained fields and lysimeters receiving contrasting rates and sources of nitrogen

Leaching of nitrogen from arable land can lead to pollution of groundwater and surface water. Various measures have been implemented in agriculture to reduce leaching, but there is still potential to do more. To find the best agricultural management regime to limit the problem, leaching from soils under different management must be measured. Different methods to estimate leaching are available, but they have not been thoroughly evaluated. This study compared (a) leaching of nitrogen from five different fertilizer treatments differing in amount and source (mineral and organic) of nitrogen and (b) two different methods for measuring leaching (tile-drained field plots and lysimeters). Nitrogen leaching from five different fertilizer treatments was studied for three years in a tile-drained field facility and for three of the treatments also for 16 months in a lysimeter facility. Leaching from organic and mineral nitrogen sources was similar in the three-year field study. Mineral nitrogen input above the economic optimum tended to give greater leaching (by 24%–43%) than nitrogen input at the expected optimum. Measurements in lysimeters and tile-drained field plots gave similar results, although leaching values tended to be slightly higher (by 18%–25%) in the tile-drained field. Overall, both facilities give reliable estimates of nitrogen leaching and are suitable for leaching studies.