Andrzej Kotecki

Progress in upscaling Miscanthus biomass production for the European bio-economy with seed-based hybrids

Field trials in Europe with Miscanthus over the past 25 years have demonstrated that interspecies hybrids such as M. × giganteus (M × g) combine both high yield potentials and low inputs in a wide range of soils and climates. Miscanthus hybrids are expected to play a major role in the provision of perennial lignocellulosic biomass across much of Europe as part of a lower carbon economy. However, even with favourable policies in some European countries, uptake has been slow. M × g, as a sterile clone, can only be propagated vegetatively, which leads to high establishment costs and low multiplication rates. Consequently, a decade ago, a strategic decision to develop rapidly multiplied seeded hybrids was taken. To make progress on this goal, we have (1) harnessed the genetic diversity in Miscanthus by crossing and progeny testing thousands of parental combinations to select several candidate seed‐based hybrids adapted to European environments, (2) established field scale seed production methods with annual multiplication factors >1500×, (3) developed the agronomy for establishing large stands from seed sown plug plants to reduce establishment times by a year compared to M × g, (4) trialled a range of harvest techniques to improve compositional quality and logistics on a large scale, (5) performed spatial analyses of yield potential and land availability to identify regional opportunities across Europe and doubled the area within the bio‐climatic envelope, (6) considered on‐farm economic, practical and environmental benefits that can be attractive to growers. The technical barriers to adoption have now been overcome sufficiently such that Miscanthus is ready to use as a low‐carbon feedstock in the European bio‐economy.

Chalcone Synthase (CHS) Gene Suppression in Flax Leads to Changes in Wall Synthesis and Sensing Genes, Cell Wall Chemistry and Stem Morphology Parameters

The chalcone synthase (CHS) gene controls the first step in the flavonoid biosynthesis. In flax, CHS down-regulation resulted in tannin accumulation and reduction in lignin synthesis, but plant growth was not affected. This suggests that lignin content and thus cell wall characteristics might be modulated through CHS activity. This study investigated the possibility that CHS affects cell wall sensing as well as polymer content and arrangement. CHS-suppressed and thus lignin-reduced plants showed significant changes in expression of genes involved in both synthesis of components and cell wall sensing. This was accompanied by increased levels of cellulose and hemicellulose. CHS-reduced flax also showed significant changes in morphology and arrangement of the cell wall. The stem tissue layers were enlarged averagely twofold compared to the control, and the number of fiber cells more than doubled. The stem morphology changes were accompanied by reduction of the crystallinity index of the cell wall. CHS silencing induces a signal transduction cascade that leads to modification of plant metabolism in a wide range and thus cell wall structure.

Thrips (Thysanoptera) associated with two morphological forms of Andean lupin (Lupinus mutabilis)

Abstract The aim of this study was to determine thrips abundance, species composition, sex ratio and seasonal dynamics of these insects on two morphological forms of Andean lupin (epigonal and semiepigonal). Thrips were studied in the lupine plants sown at two dates at the Experimental Research Station at Pawłowice, near Wrocław, Lower Silesia, Poland, during two growing seasons (2011-2012). The experiment was designed as a split-plot with four replicates for each morphological form and time of sowing. For the determination of thrips species’ composition, plants were collected from the central part of each plot when lupin was at the full blooming stage. In the laboratory, plants were shaken over a sheet of white paper. Once in each season thrips were also collected with a sweep net. In the laboratory larvae and adults were identified to species level and separated into males and females. During the whole lupin growing season, insects were also counted weekly on 10 consecutive plants in the middle row of each plot. Frankliniella intonsa, Thrips major and Aeolothrips intermedius were the dominant species in the full blooming stage of both semiepigonal and epigonal forms of Andean lupin. Thrips tabaci also occurred in greater numbers. There were no significant differences between numbers of thrips and number of species occurring on semiepigonal and epigonal plants sown at the same time. In the most numerous species, like F. intonsa and T. major, mainly females occurred in their population. In the population of A. intermedius males were abundant. Thrips occurring in Lupinus mutabilis, irrespective of the used form of lupin or sowing time, had one peak of abundance, i.e., the last ten days of June and the first ten days of July, when plants were at the blooming stage.

Response of Prairie cordgrass (Spartina pectinata Link) to a residual effect of municipal sewage sludge application

Abstract The objective of our study was to assess the residual effect of sewage sludge on the growth and yield of Prairie cordgrass and the content of crude ash, macroelements and heavy metals in the plant biomass. Field trials conducted in the years 2011 to 2013 focused on the assessment of the impact of municipal sewage sludge applied from 2008 to 2010on the growth and yield of Prairie cordgrass. The experiments followed the split-plot design with two variables: the rate of sewage sludge (DM-dry matter) at 0, 1.4, 2.8 and 4.2 t ha-1, corresponding to nitrogen fertilization with: 0, 50, 100, 150 kg ha-1, and the harvest time - fall and winter. The total dose of sewage sludge applied in 2008−2010 was 0, 4.2, 8.4 and 12.6 t DM ha-1, which corresponded to the total dose of nitrogen fertilization: 0, 150, 300 and 450 kg ha-1, respectively. The municipal sewage sludge at a rate of 8.4 t DM ha-1, compared to the Control, significantly increased the number of leaves per plant, the leaf and culm matter, the number of shoots per 1 m2, the dry matter yield, crude ash deposition and uptake of macroelements and heavy metals. Graphical Abstract