Productivity and quality parameters of <i>Allium fistulosum</i> L.

The growing demand for non-traditional plant products encourages research into new plant species and cultivars. Allium fistulosum is the earliest leafy plant cultivated in the open field in Lithuania. Therefore, it is important to study plant cultivars and determine the harvesting time to obtain quality products. The study was conducted in the experimental vegetable field of the Institute of Horticulture of the Lithuanian Research Centre for Agriculture and Forestry in 2022–2023. The phenological stages of two different cultivars, morphological characteristics, productivity, and the plant's winter hardiness were observed. Measurements were performed and harvest was done three times: in spring, summer, and autumn. The results showed that genetic origin and harvesting time influenced differences in the morphometric parameters, productivity, and ascorbic acid accumulation of A. fistulosum cultivars. Cultivar ‘Bajkal’ is distinguished with longer and wider foliage, the highest productivity rate, and better adaptivity. This cultivar's most intensive plant growth was determined in autumn, but the highest weight of the plant reaching 0.5 kg was determined in spring. Cultivar ‘Marozka’ is distinguished by the higher ability of ascorbic acid accumulation compared with the cultivar ‘Bajkal’. The content of ascorbic acids reached 34.9 mg g−1 of cultivar ‘Marozka’ during the spring harvesting and up to 8,8 mg g−1 of ‘Bajkal’, respectively. The total sugar amount and weight of dry matter were more intensive in spring for both cultivars. In the cultivars ‘Marozka’ and ‘Bajkal’ leaves were found a higher amount of nitrates at 45.7 and 50.9 mg kg −1 in autumn.