Influence of soil drought on some biomorphological indicators and Allium cepa L. varieties performance

In the article in 2020-2022, locally improved onion varieties Govsan and Sabir, depending on irrigation regimes (normal watering - 12 times, control, 8 times - hard mode, 4 times - acute mode) during the growing season, some biomorphological indicators - height plants. the number of leaves, the mass of the aerial part, the mass of leaves, “false” stems, roots and bulbs, the length and diameter of the bulbs, the bulb index - and the results of changes in the amount of total wet biomass and plant productivity. light bulbs are presented. It has been shown that biomorphological changes in different onion varieties manifest themselves differently depending on the growth phases and irrigation regime. Artificial soil drought negatively affects the biomorphological parameters of the studied varieties (with the exception of roots, i. e. soil drought does not have a serious effect on the mass of roots) and as a result, the productivity of both varieties decreases, but this decrease is higher in the locally improved variety Govsan than in the relatively drought-resistant Sabir variety. happens. It was found that in the locally improved variety Govsan in acute mode the amount of total wet biomass decreased by 41.3-49.5%, and the weight of the bulbs - by 33.6-52% compared to the control, and in the variety Sabir - which is more stable to drought, these indicators decreased by 20.2 and amounted to 40.2% and 26.5-38.4%. In this regard, the hard regime occupies an intermediate position, that is, in this regime, soil drought does not significantly affect the onion yield, and the yield loss is 7.2-29.6% in Locally Improved Govsan, and 3.2-25% in Sabira. Therefore, in the economic regions of Mil-Mugan and Karabakh, where onions are grown, if there is a serious water shortage in the summer months, it is enough to water this plant 8 times instead of 12, which allows you to save a significant amount. irrigation water (at least 2000 m3/ha).