Planting dates and row spacing influence on biometric indicators and productivity of Clary sage plants (Salvia solaria L.)

Abstract

Potential crop productivity can be achieved under meeting the requirements on biological needs of crops on their nutrition area twith essential number of nutrients, optimum temperature, lighting and moisture supply. Growing medicinal and essential oil crops leads to uneven seedling in unstable temperature conditions of the spring period. Therefore, it is important to determine the favorable time for sowing, as well as the optimal placement of plants in the area aimed at the seed germination energy growth as well as good and even sprouts. Sowing time and methods influenced Clary sage seeds germination. The highest seed germination rate was observed with a sowing period of April 15 and a wide-row sowing method of 45 cm – 92,3 %. These techniques contributed to better survival of Clary sage plants at the end of the growing season (fruit formation phase) as well, the figure was 95,1 %. The highest growth rate of Clary sage (6.1–14.1) cm was observed in the period of complete formation of leaves rosette. By the budding phase, its growth was slow – 2–3 cm in ten days, and from budding to flowering the crops growth rates significantly increased to 8–10 cm. After the flowering phase, the growth of Clary sage decreased, which ensured a uniform redistribution of nutrients from the vegetative to generative part. The greatest crops height was noted for the winter period of sowing and row spacing of 15 cm (31.8 cm). A change in the ratio of accumulation of crops green mass parts (stems, leaves, inflorescences) was observed in the process of Clary sage growth and development. So, in the budding phase, the share of leaves was 1.9–2.9 % of the total plant weight and in the fruit formation phase it made 3.6–5.9 %. The same trend was observed in the change of the total stems weight. An increase in the row spacing (up to 45) influenced the growth of Clary sage biomass. In the fruit formation phase, the total plant weight increased by 0.4–3.1 g in comparison with that under 15 cm row spacing Late sowing dates for Clary sage (April 15) contributed to the formation of a larger number of stems, leaves and inflorescences on the plant. The total number and productive inflorescences was larger under 15 cm width method of sowing, which is more than those compared with the wide-row sowing of 45 cm. Solid sowing method (15 cm)provides a larger number of Clary sage stalks, but only in subwinter sowing. Indicators of individual productivity of Clary sage such as stems, leaves and inflorescences number determine the optimal application of growing technology methods to realize the potential of this crop. The most favorable conditions for Clary sage high productivity formation are created for a sowing period of April 15. Maximum values of crop production were obtained with a row spacing of 30 cm. The enhancement of plant density (with a row spacing of 15 cm) results in Clary sage productive inflorescences number increase. Consequently, the maximum values for Clary sage plants (average data for the experimental sites) were noted with a sowing period of April 15 with 45 cm row spacing (plant weight – 17.6 g, leaves weight – 5.7 g, inflorescences weight – 5.3 g). Key words: Clary sage, sowing time, row spacing, phenological phases, green weight, leaves, inflorescences.