Chemical composition of onion varieties (Allium cepa L.)

Abstract

Onion (Allium cepa L.) is one of the most important vegetable crops widely cultivated throughout the world. The study of its chemical composition is of particular relevance due to the need to optimize cultivation technologies for obtaining products with high nutritional and medicinal properties. The aim of the research was to study the effect of different seeding rates of sets on the chemical composition of bulbs of onion varieties Strigunovsky mestny, Iglinsky 2, and Red Baron. Three-year field and laboratory studies were conducted in 2021–2023 on leached chernozem in the conditions of the Southern forest-steppe of the Republic of Bashkortostan at the Bashkir State Agrarian University. Four seeding rates were studied: 0.9; 1.0; 1.1; 1.2 million pcs./ha. The content of dry matter, total nitrogen, phosphorus, and potassium in bulbs was determined. It was established that with an increase in the seeding rate from 0.9 to 1.2 million pcs./ha, a consistent and statistically significant decrease in all studied parameters was observed for all varieties. The maximum accumulation of dry matter (15.6%), nitrogen (1.52%), phosphorus (0.58%), and potassium (1.92%) was noted in the Iglinsky 2 variety at the minimum seeding rate of 0.9 million pcs./ha. The lowest values of all parameters were recorded at the maximum seeding rate of 1.2 million pcs./ha. Varietal differences in chemical composition are most pronounced at a low seeding rate and become less pronounced with an increase in plant density. The Iglinsky 2 variety is characterized by the highest accumulation of all studied nutrient elements. The results obtained can be used to optimize the technology of onion cultivation in the forest-steppe zone.