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Eggplant (Solanum melongena L.) is one of the most popular common major vegetable crops worldwide. This study evaluated the nutritional content of seven commercial eggplant fruits in terms of fatty acid, mineral, sugar, organic acid, amino acid and polyamine contents. The most abundant fatty acid was linoleic acid (range, 39.14-53.81%, ave. 45%), and the most abundant mineral was K (range, 1556.2-3171.6 mg/kg fw, ave. 2331.9). The major organic acid was malic acid (range, 129.87-387.01 mg/g fw, ave. 157.49), and the major sugar was fructose (range, 1242.81- 1379.77 mg/100 g fw, ave. 1350.88). The major polyamine was putrescine (11.54 and 25.70 nmol/g fw, ave. 17.86), and the major amino acid was glutamine (148.4 and 298.75 mg/100 g fw, ave. 219.74). Overall, taking into account the export potential of eggplants, these results may contribute to further studies aiming to improve other nutrient-rich varieties of eggplant in breeding programs.

Main conclusion: Isoprenoid and aromatic cytokinins occur in poplar as free compounds and constituents of tRNA, poplar isopentenyltransferases are involved in the production of isoprenoid cytokinins, while biosynthesis of their aromatic counterparts remains unsolved. Cytokinins are phytohormones with a fundamental role in the regulation of plant growth and development. They occur naturally either as isoprenoid or aromatic derivatives, but the latter are quite rare and less studied. Here, the spatial expression of all nine isopentenyl transferase genes of Populus × canadensis cv. Robusta (PcIPTs) as analyzed by RT-qPCR revealed a tissue preference and strong differences in expression levels for the different adenylate and tRNA PcIPTs. Together with their phylogeny, this result suggests a functional diversification for the different PcIPT proteins. Additionally, the majority of PcIPT genes were cloned and expressed in Arabidopsis thaliana under an inducible promoter. The cytokinin levels measured in the Arabidopsis-overexpressing lines as well as their phenotype indicate that the studied adenylate and tRNA PcIPT proteins are functional in vivo and thus will contribute to the cytokinin pool in poplar. We screened the cytokinin content in leaves of 12 Populus species by ultra-high performance-tandem mass spectrometry (UHPLC-MS/MS) and discovered that the capacity to produce not only isoprenoid, but also aromatic cytokinins is widespread amongst the Populus accessions studied. Important for future studies is that the levels of aromatic cytokinins transiently increase after daybreak and are much higher in older plants. [ABSTRACT FROM AUTHOR]

LONELY GUY ( LOG) genes encode cytokinin riboside 5′-monophosphate phosphoribohydrolases and are directly involved in the activation of cytokinins., To assess whether LOG proteins affect the influence of cytokinin on nodulation, we studied two LOG genes of Medicago truncatula., Expression analysis showed that Mt LOG1 and Mt LOG2 were upregulated during nodulation in a CRE1-dependent manner. Expression was mainly localized in the dividing cells of the nodule primordium. In addition, RNA interference revealed that Mt LOG1 is involved in nodule development and that the gene plays a negative role in lateral root development. Ectopic expression of Mt LOG1 resulted in a change in cytokinin homeostasis, triggered cytokinin-inducible genes and produced roots with enlarged vascular tissues and shortened primary roots. In addition, those 35S: LOG1 roots also displayed fewer nodules than the wild-type. This inhibition in nodule formation was local, independent of the SUPER NUMERIC NODULES gene, but coincided with an upregulation of the Mt CLE13 gene, encoding a CLAVATA3/ EMBRYO SURROUNDING REGION peptide., In conclusion, we demonstrate that in M. truncatula LOG proteins might be implicated in nodule primordium development and lateral root formation. [ABSTRACT FROM AUTHOR]