ANALYSIS OF FLUCTUATING ASYMMETRY OF BILATERAL TRAITS OF CUCUMBER SEEDLINGS GROWN UNDER RADIATION WITH DIFFERENT LIGHT QUALITY
The article considers the choice and analysis of the bilateral trait, the fluctuating asymmetry value of which responds to the changes of light quality of radiation source. Research was conducted on cucumber seedlings of Safaa F1 variety, which were grown in controlled environment before the emergence of the second true leaf. Illumination level in both variants of the experiment was 22.5 W∙m-2. The ratio of the emission intensity between three spectral bands (blue, green and red ) for Irradiator №1 was : : = 33 % : 34 % : 33 %, and for Irradiator № 2 - : : = 03 % : 54 % : 38 %. Of the ten bilateral traits, chosen for the analysis, only the trait associated with optical density on cotyledons under light transmission in the blue range of the spectrum (Db) can be used to assess the quality of the spectral environment of cultivated cucumber plants. Values of fluctuating asymmetry for the trait Db in the experiment differ 1.87 times and are 0.0098 under Irradiator №1 and 0.0183 under Irradiator № 2. Statistical processing of the bilateral trait Db data revealed the absence of directional asymmetry that is a diagnostic indicator of the fluctuating asymmetry. The lack of correlation of size dependence |L-R|/((L+R)/2) does not allow to use properly normalization of |L-R|/(L+R) type in order to obtain the asymmetry value in the range from 0 to 1. The fluctuating asymmetry values of the bilateral trait Db may be used in the audit of indoor plant lighting to estimate the light environment for cucumber cultivation.