Hybrid breeding for biomass yield in winter triticale: II. Combining ability and hybrid prediction

Accurate hybrid prediction and knowledge about the relative contribution of general (GCA) and specific combining ability (SCA) are of utmost importance for efficient hybrid breeding. We therefore evaluated 91 triticale single-cross hybrids in field trials at seven environments for plant height, heading time, fresh biomass, dry matter content and dry biomass. Fresh and dry biomass showed the highest proportion (23%) of variance due to SCA. Prediction accuracies based on GCA were slightly higher than based on mid-parent values. Utilizing parental kinship information yielded the highest prediction accuracies when both parental lines have been tested in other hybrid combinations, but still moderate-to-low prediction accuracies for two untested parents. Thus, hybrid prediction for biomass traits in triticale is currently promising based on mid-parent values as emphasized by our simulation study, but can be expected to shift to GCA-based prediction with an increasing importance of GCA due to selection in hybrid breeding. Moreover, the performance of potential hybrids between newly developed lines can be predicted with moderate accuracy using genomic relationship information.     

Exploiting trap color to improve surveys of longhorn beetles

Journal of Pest Science - Longhorn beetles are commonly moved among continents within wood packaging materials used in trades. Visual inspections carried out at points of entry often fail to detect...     

Moisture-dependent elastic characteristics of walnut and cherry wood by means of mechanical and ultrasonic test incorporating three different ultrasound data evaluation techniques

Ultrasonic testing is a non-destructive testing method of choice for estimating the anisotropic elastic properties of wood materials. This method is reliable for estimating the Young’s and shear moduli. However, its applicability to Poisson’s ratios remains uncertain. On the other hand, despite their destructive nature, mechanical tests allow a direct measurement of all elastic properties including the Poisson’s ratios. In some cases (e.g. when assessing cultural heritage objects), destructive testing may not be an option. In this work, two types of hardwood walnut (Juglans regia L.) and cherry (Prunus avium L.), which often appear on cultural heritage objects, were tested using both ultrasonic and mechanical testing methods under four different moisture conditions below fibre saturation point. The results show that a higher moisture condition leads to a decrease in material elasticity. For walnut wood, their longitudinal Young’s modulus (\(E_{\rm L}\)) was reduced by 679 MPa under the compression load for a one per cent increase in moisture content. Moreover, three ultrasound data evaluation techniques, which differ in the way they incorporate the Poisson’s ratios (full stiffness inversion, simplified uncorrected, and simplified corrected), were used to estimate the Young’s moduli (E). The main goal is to obtain reliable material parameters using the ultrasound test. As a result, it is concluded that the chosen data evaluation method influences the accuracy of the calculated E. In a certain case, the simplified-corrected method, which requires only one specimen type, gave a closer agreement to mechanical tests (e.g. \(\Delta E_{\rm T}=6\,\%\) deviation on mechanical results). In another case, the full-stiffness-inversion method, which requires four specimen types, gave the best estimation (e.g. \(\Delta E_{\rm L}=2\,\%\)). In this corresponding direction, the simplified-corrected method can only partially reduce the overestimation of the simplified uncorrected from \(\Delta E_{\rm L}=47\) to 32 %. The variation of E produced by different evaluation procedures is due to the different correction factor values, which is a consequence of the variation in \(\nu\).     

Measurement of tidal volume using Respiratory Ultrasonic Plethysmography in anaesthetized,mechanically ventilated horses

ObjectiveTo compare tidal volume estimations obtained from Respiratory Ultrasonic Plethysmography (RUP) with simultaneous spirometric measurements in anaesthetized, mechanically ventilated horses.Study designProspective randomized experimental study.AnimalsFive experimental horses.MethodsFive horses were anaesthetized twice (1 week apart) in random order in lateral and in dorsal recumbency. Nine ventilation modes (treatments) were scheduled in random order (each lasting 4 minutes) applying combinations of different tidal volumes (8, 10, 12 mL kg^?1) and positive end-expiratory pressures (PEEP) (0, 10, 20 cm H₂O). Baseline ventilation mode (tidal volume = 15 mL kg^?1, PEEP = 0 cm H₂O) was applied for 4 minutes between all treatments. Spirometry and RUP data were downloaded to personal computers. Linear regression analyses (RUP versus spirometric tidal volume) were performed using different subsets of data. Additonally RUP was calibrated against spirometry using a regression equation for all RUP signal values (thoracic, abdominal and combined) with all data collectively and also by an individually determined best regression equation (highest R²) for each experiment (horse versus recumbency) separately. Agreement between methods was assessed with Bland-Altman analyses.ResultsThe highest correlation of RUP and spirometric tidal volume (R² = 0.81) was found with the combined RUP signal in horses in lateral recumbency and ventilated without PEEP. The bias ± 2 SD was 0 ± 2.66 L when RUP was calibrated for collective data, but decreased to 0 ± 0.87 L when RUP was calibrated with individual data.Conclusions and clinical relevanceA possible use of RUP for tidal volume measurement during IPPV needs individual calibration to obtain limits of agreement within ± 20%.     

Summer drought decreases Leymus chinensis productivity through constraining the bud,tiller and shoot production

Extreme drought events can directly decrease productivity in perennial grasslands. However, for rhizomatous perennial grasses it remains unknown how drought events influence the belowground bud bank which determines future productivity. Ninety‐day‐long drought events imposed on Leymus chinensis, a rhizomatous perennial grass, caused a 41% decrease in the aboveground biomass and a 28% decrease in belowground biomass. Aboveground biomass decreased due to decrease in both the parent and the daughter shoot biomass. The decreases in daughter shoot biomass were due to reductions in both the shoot number and each individual shoot weight. Most importantly, drought decreased the bud bank density by 56%. In addition, drought induced a bud allocation change that decreased by 41% the proportion of buds that developed into shoots and a 41% increase in the buds that developed into rhizomes. Above results were supported by our field experiment with watering treatments. Thus, a 90‐day‐long summer drought event decreases not only current productivity but also future productivity, because the drought reduces the absolute bud number. However, plasticity in plant development does partly compensate for this reduction in bud number by increasing bud development into rhizomes, which increases the relative allocation of buds into future shoots, at the cost of a decrease in current shoots.     

Combining agent-based and stock-flow modelling approaches in a participative analysis of the integrated land system in Reichraming, Austria

The integrated modelling of coupled socio-ecological systems in land-change science requires innovative model concepts capable of grasping the interrelations between socioeconomic and natural components. Here, we discuss the integrated socio-ecological model SERD (Simulation of Ecological Compatibility of Regional Development) that was developed for the municipality of Reichraming in Upper Austria in a participative 2-year process involving local stakeholders. SERD includes three main components: (1) an agent-based actors module that simulates decisions of farmsteads, the municipal administration and other important actors; (2) a spatially explicit (GIS based) land-use module that simulates land-use change at the level of individual parcels of land and (3) an integrated socio-ecological stock-flow module that simulates carbon and nitrogen flows through both socioeconomic and ecological system compartments. We report on outcomes of a scenario analysis that outlines possible future trajectories depending on both external (e.g. agricultural subsidies and prices) and internal (e.g. innovation, willingness to co-operate) factors. We find that both external and internal factors can affect the behaviour of the integrated system considerably. Local and regional policies are found to be able to counteract adverse global socioeconomic conditions to some extent, but not to reverse the trend altogether. We also find strong interdependencies between socioeconomic and ecological components of the system. Fully evaluating these interdependencies is, however, not possible at the local scale alone and will require explicit consideration of higher-level effects in future research.     

Influence of mycotoxin producing fungi (Fusarium, Aspergillus, Penicillium) on gluten proteins during suboptimal storage of wheat after harvest and competitive interactions between field and storage fungi

Cereals contaminated by Aspergillus spp., Penicillium spp., and Fusarium spp. and their mycotoxins, for example, ochratoxin A (OTA) and deoxynivalenol (DON), are not only a risk to human and animal health but can also show poor technological properties and baking quality. The influence of these genera on the sulfur speciation of low molecular weight (LMW) subunits of glutenin was characterized by investigating suboptimally stored wheat samples in situ by X-ray absorption near edge structure (XANES) spectroscopy and baking tests. Field fungi of the genus Fusarium have hardly any influence on both the sulfur speciation of wheat gluten proteins and the baking properties, whereas storage fungi of the genera Aspergillus and Penicillium have a direct influence. An increased amount of sulfur in sulfonic acid state was found, which is not available for thiol/disulfide exchange reactions in the gluten network, and thus leads to a considerably reduced baking volume. From changes of the composition of the mould flora during suboptimal storage of wheat and from the mycotoxin contents, it can be concluded that microbial competitive interactions play an important role in the development of the mould flora and the mycotoxin concentrations during (suboptimal) storage of wheat.