Water for agriculture: more crop per drop.

Global crop production in agriculture depends on water availability. Future scenarios predict increasing occurrence of flash floods and rapidly developing droughts accompanied by heatwaves in humid regions that rely on rain-fed agriculture. It is challenging to maintain high crop yields, even in arid and drought-prone regions that depend on irrigation. The average water demand of crops varies significantly, depending on plant species, development stage, and climate. Most crops, such as maize and wheat, require relatively more water during the vegetative phase compared to the ripening phase. In this review, we explain WUE and options to improve water use and thus crop yield. Nutrient management might represent another possibility to manipulate water uptake and use by plants. An emerging topic involves agroforest co-cultivation, where trees in the system facilitate water transfer through hydraulic lift, benefiting neighbouring crops. Other options to enhance crop yield per water use are discussed.

Training grapevines generates a metabolomic signature of wine.

Training systems are an option to handle the pronounced apical dominance of grapevines and to influence diverse traits of the corresponding wine. However, it is still unclear if different training systems generate signatures in the metabolome of the wine. By an untargeted metabolomics approach using (SPME) GC-MS wine (volatiles) and leaves were evaluated. Different training directions such as vertical shoot positioning systems, hanging shoot systems, and minimal pruning systems were distinguishable in wine. It was shown, that different training systems generate a metabolomic signature in the wine which was more pronounced than in leaves. Moreover, the sensory analysis showed some changes in the aroma of the different training systems. Thus, the influence of the training system ranges from the leaf metabolome to the wine metabolome.

Sodium accumulation has minimal effect on metabolite profile of onion bulbs.

Onions (Allium cepa L.) are considered a salt-sensitive crop. However, to date, little evidence supports this claim and information about the physiological and metabolomic effects of Na+ accumulation in onion plants is lacking. The purpose of our research has been to assess changes in onion bulbs of three different cultivars after soil and foliar applications with moderate doses of chloride-free Na2SO4. The antioxidative defense mechanism in onion and the accumulation of Na+ within the plant has also been analyzed. Based on Na+ leaf and bulb concentrations, our findings demonstrate that Na+ is only transported from bulbs to leaves not vice versa, therefore foliar application does not lead to Na+ accumulation in the bulbs. Soil application with Na2SO4 results in an accumulation of Na+ in the leaves and bulbs, but with the exception of one onion variety this accumulation does not alter the metabolite profile of onions significantly. Even the K+ concentration and organic solute levels are unchanged after accumulation of Na+. Nevertheless, after Na2SO4 treatment, the antioxidative defense system moderately increases in onion bulbs. This study demonstrates that onion plants have the ability to exclude Na+ at moderate Na2SO4 treatment, and that the potential for quality onion production in soils with increased sodium concentration is much higher than previously assumed.

Drought and crop yield.

Episodes of water shortage occur in most agricultural regions of the world. Their durations and intensities increase, and their seasonal timing alters with changing climate. During the ontogenic cycle of crop plants, each development stage, such as seed germination, seedling establishment, vegetative root and shoot growth, flowering, pollination and seed and fruit development, is specifically sensitive to dehydration. Desiccation threatens yield and leads to specific patterns, depending on the type of crop plant and the harvested plant parts, e.g. leafy vegetables, tubers, tap roots or fruits. This review summarizes the effects of drought stress on crop plants and relates the dehydration-dependent yield penalty to the harvested organ and tissue. The control of shoot transpiration and the reorganization of root architecture are of core importance for maintaining proper plant water relationships. Upon dehydration, the provision and partitioning of assimilates and the uptake and distribution of nutrients define remaining growth activity. Domestication of crops by selection for high yield under high input has restricted the genetic repertoire for achieving drought stress tolerance. Introgression of suitable alleles from wild relatives into commercial cultivars might improve the ability to grow with less water. Future research activities should focus more on field studies in order to generate more realistic improvements to crops. Robotic field phenotyping should be integrated into genetic mapping for the identification of relevant traits.

Metabolite profiling of onion landraces and the cold storage effect.

Today, commercial onion breeders focus almost entirely on conventional farming which reduces diversity in the market and leads to loss of desirable traits such as those that impact nutritional and sensory aspects of onions. A way to preserve phenotypic and genetic diversity is to re-evaluate traditional landraces to introduce their benefits to the broader public. Common onion genotypes vary greatly in their storability. In particular, temperature and relative humidity during storage have significant impact on the metabolites in onions after storage. The aim of this study was to assess changes in the metabolite profile of ten onion genotypes after five months of cold storage. In addition, a characterization of onion landraces in their fresh state was also conducted in order to compare their properties against a commercial genotype. Onion genotypes were grown under organic farming conditions. After harvest and curing, bulbs were stored for up to 22 weeks. Before and after storage, bulb samples were analyzed through targeted and untargeted methods. Out of 189 identified metabolites, 128 showed a storage effect. Mainly fructans decreased because of respiration and energy demand, while monosaccharides increased. Further, amino acids were altered in their concentration after storage with an effect on aroma precursors. Eight of the nine landraces had good storability without critical losses. In their fresh state, the onion genotypes clustered into three major groups. For instance, landraces of group III showed consistently and substantially higher levels of amino acids and certain sugars, indicating a high potential of aromatic properties in those onion landraces.

Salinity and crop yield.

Thirty crop species provide 90% of our food, most of which display severe yield losses under moderate salinity. Securing and augmenting agricultural yield in times of global warming and population increase is urgent and should, aside from ameliorating saline soils, include attempts to increase crop plant salt tolerance. This short review provides an overview of the processes that limit growth and yield in saline conditions. Yield is reduced if soil salinity surpasses crop-specific thresholds, with cotton, barley and sugar beet being highly tolerant, while sweet potato, wheat and maize display high sensitivity. Apart from Na+ , also Cl- , Mg2+ , SO4 2- or HCO3 - contribute to salt toxicity. The inhibition of biochemical or physiological processes cause imbalance in metabolism and cell signalling and enhance the production of reactive oxygen species interfering with cell redox and energy state. Plant development and root patterning is disturbed, and this response depends on redox and reactive oxygen species signalling, calcium and plant hormones. The interlink of the physiological understanding of tolerance processes from molecular processes as well as the agronomical techniques for stabilizing growth and yield and their interlinks might help improving our crops for future demand and will provide improvement for cultivating crops in saline environment.

[Successful thrombolysis of a massive pulmonary embolism following pneumonectomy]. / Erfolgreiche Thrombolyse einer massiven Lungenembolie nach Pneumektomie.

Pulmonary embolism is a rare but life-threatening complication after major lung surgery. The case of a patient with sudden onset of hemodynamic instability 2 days after right-sided pneumonectomy is reported. After finding massive right ventricular dysfunction by transthoracic echocardiography and detection of an embolism by computed tomography, a successful and uneventful thrombolysis was performed. The risks and benefits of this procedure are discussed with reference to the literature.

[Expression of CD44 isoforms--a new histopathologic parameter in colorectal carcinoma?]. / Expression von CD44 Isoformen-ein neuer histopathologischer Parameter beim kolorektalen Karzinom?

Expression of CD44H and CD44-isoforms were examined by immunohistochemistry in 102 patients with colorectal tumors in correlation to histological grading, staging and clinical outcome. From normal mucosa to colorectal tumors we found an upregulation of CD44H and CD44-v9 and a de-novo expression of CD44-v6. When compared to histological grading it was found that CD44-v6 expression indicates more differentiated tumors in contrast to less differentiated colorectal carcinomas showing decreasing CD44-v6 expression. Further we came to the result that increasing CD44-v6 expression correlates with progressive tumor stage. In the metastases we found a significant decrease in expression of CD44H, CD44-v9 and-v6 when compared to corresponding primary colorectal tumors. Wether the differential CD44 expression can be used as a prognostic histopathological marker for the progression of colorectal cancer has to be further validated. For final interpretation, our prospective study has to be continued further.