Influence of various fractions of ultrafine humato-saproel suspension on the growth, development and quality of basil (Ocimum basilicum L.) products in comparison with chemical fertilizers

Abstract

The paper presents the results of a study of the effect of various fractions of humic acids (humic and fulvic acids), extracted from ultrafine humic-sapropel suspension, on the growth and development of various varieties of basil used for medicinal purposes. The plants were grown in a closed grow box for 50 days, while maintaining a stable internal microclimate and an optimal level of insolation for the culture inside the working area. Four varieties of commercial use were chosen as objects for the study: Green Large (mid-ripening), Emily (early-ripening), Lemona (early-ripening) and Marian (early-ripening). A soil mixture consisting of 50 % vermiculite and 50 % peaty-gley soil was used as a solid substrate for sowing seeds: the total organic content was 30.4 %; Ntotal - 1.4 %; pHKCl - 5.57; mobile forms P2O5- 8.8 and K2O - 8.2 mg/kg. Both fractions of humic acids were added as dilute solutions at a concentration of 0.01 %. The treatment of plants was carried out by alternating two methods: a single application of each fraction separately according to the options under the root, and a foliar method, when spraying the leaves once a week. In the control variant, 1.0 N water was used for irrigation during the entire growing season. Knop nutrient solution without humic acid additives. The results of morphometric and chemical analyzes showed that the Lemon variety proved to be the best candidate for further scientific research. The treated plants did not differ in height and biomass from the controls (average 29.75 mg in treatment versus 29.00 mg in control). The best organization in the diet, based on the calculation of element structural coherence indices, also resulted in a slight decrease in the efficiency of photosynthesis in this variety, which is indirectly indicated by the values of the SPAD chlorophyll optic counter (31.98 units on average during processing, against 35.54 units on the control). It is concluded that due to the introduction of organic additives, the variety spends the least amount of energy for its growth, even in a substrate depleted in elements.