Rich diversity in cultivated Finnish potato onions (Allium cepa var. aggregatum G. Don)

Potato onion (Allium cepa var. aggregatum G. Don) remained the most widely grown onion type in Finland up to the 1950’s, after which the more productive cultivars of common onion replaced this vegetatively propagated onion type. The Finnish accessions have been maintained in two national plant genetic resources (PGR) collections since 1990’s but new samples have been obtained still later. In this research, we analysed the genetic diversity of potato onions and shallots, grown in home gardens and in PGR collection, and compared the uniformity of the two PGR collections. One hundred ten onion samples were analysed using eight microsatellite loci, which amplified 83 alleles in total. There was a large number of genetically different samples, forming four major groups in the dendrogram. The results show that there is still a lot of genetic diversity among the Finnish potato onions, even though they are propagated vegetatively. The rich diversity in the samples obtained from citizens reflects a valuable source of genetic resources maintained by home gardeners. The national collection has been updated on the basis of the results. To ensure the preservation of the rich onion heritage, efforts are needed to increase the availability of potato onion to home gardeners and commercial growers.

Comparison of Organosulfur and Amino Acid Composition between Triploid Onion Allium cornutum Clementi ex Visiani, 1842, and Common Onion Allium cepa L., and Evidences for Antiproliferative Activity of Their Extracts

Species that belong to the genus Allium have been widely used for human food and traditional medicine. Their beneficial health effects, as well as the specific aroma, are associated with their bioactive chemical compounds, such as sulfur compounds and flavonoids. Gas chromatography and mass spectrometry (GC–MS) and reverse-phase high-performance liquid chromatography (reverse-phase HPLC) were used to identify organosulfur and amino acid content of triploid hybrid onion, Allium cornutum Clement ex Visiani, 1842, and common onion, Allium cepa L. Allium extracts were tested for their antiproliferative activity in three human cancer cell lines (HeLa, HCT116, and U2OS). DNA fragmentation and DAPI staining analysis were performed on HeLa cells to evaluate the effect of extracts on DNA damage and cell morphology. The mRNA expression of p53, Bax, and Caspase-3 genes involved in apoptosis were analyzed by real-time PCR. Using GC–MS, 27 compounds were found in two Allium species headspaces. Differences were noted among the main compound abundance in the headspace (although the major thiols and disulfides were qualitatively identic in both Allium species) and dipropyl disulfide, diisopropyl trisulfide, and (Z)-prop-1-enyl propyl trisulfide were predominant sulfides. Identification of amino acids and their quantities were determined by reverse-phase HPLC. Most abundant amino acids in both onions were arginine (Arg) and glutamic acid (Glu). The results of cytotoxicity testing confirmed antiproliferative effects of both species. The DNA fragmentation assay, DAPI staining and real time PCR analysis confirmed that A. cornutum and A. cepa extracts induced apoptosis in HeLa cells. This study presents the evidence for possible therapeutic use of A. cornutum and A. cepa extracts against human cervical carcinoma cell line.

Fertilizing modes and moistening levels of common onion winter in conditions Southern of Ukraine

The research was carried out on the lands of the Mykolayiv DSDS IZZ NAAS during 2016-2018.The soil of the experimental plot is southern chernozem in the carbonate forest, which is characterized by a high content of potassium, medium contentof phosphorus and is insufficiently supplied with nitrogen. The climate is continental, characterized by sharp and frequent fluctuations of annual and monthly air temperatures, large heat reserves and aridity. It is determined that owing to the drip method of irrigation and application of mineral fertilizers optimal conditions for growth and development of winter onion plantswere created. Against the background of mineral fertilizers – 25% scattered and 75% with irrigation water – the largest number of leaves per plant (6.7-6.9 pcs.) was counted, plant height reached 57.7-58.1 cm and the bulb weight was 92.5-95.2 g. Key words: onion, winter method of cultivation, drip irrigation, fertilizer background, irrigation regime, yield, profitability.

Shallots in Croatia – genetics, morphology and nomenclature

- The term 'shallot' in Croatia denotes three genetically and morphologically different, vegetatively reproduced relatives of the common onion, Allium cepa L., which are mainly traditionally cultivated for consumption and as a spice: A. cepa Aggregatum group, (2n = 2x = 16), A. × proliferum (Moench) Schrad. (2n = 2x = 16) and A. × cornutum Clementi ex Vis. (2n = 3x = 24). This paper reviews the results of studies of their morpho- -anatomical characteristics and genetic structure. Although all three taxa were determined as varieties of the common onion, only the shallot A. cepa Aggregatum group (syn. A. ascalonicum L.) belongs to that species. The shallot A. × proliferum represents a hybrid between the two closely related species, A. cepa and A. fistulosum L. The third form of shallot, A. × cornutum is a still incompletely understood triploid hybrid between A. cepa and one or two closely related Allium species, whose identity has not been fully elucidated. In contrast to shallot A. cepa Aggregatum group, which has normal meiosis and produces fertile seed, hybrid shallots A. × proliferum and A. × cornutum are sterile, and reproduce exclusively vegetatively by underground bulbs or bulbils from the inflorescence.