PRODUCTIVITY OF ALFALFA IN THE SYSTEM OF ORGANIC PRODUCTION UNDER THE CONDITIONS OF CLIMATE CHANGE
Authors: Hetman N. Y. , Burko L. M. , Svystunova I. V. 
Published: May 2023

The article presents the results of studies of the influence of the modes of use of the grass stand on the forage productivity of different ecotypes of alfalfa. Under the conditions of climate change, alfalfa sowing formed stable productivity indicators on the organic background of fertilizer in combination with soil liming.

In the experiment, the fodder productivity of different alfalfa ecotypes was studied by Rosana (originator: Institute of Fodder and Agriculture Podillia, National Academy of Sciences) and Unitro (originator: Institute of Irrigated Agriculture, National Academy of Sciences).

An increase in the yield of leaf-stem mass in the first slope of sowing alfalfa according to the main phases of growth and development was noted, which, regardless of the varietal characteristics of the crop, was in the range of 22.4-23.5 t/ha in the budding phase, 27.6-28.4 t/ha - at the beginning of flowering and 28.3-29.2 t/ha - in flowering.

According to the modes of using alfalfa crops, the height of the plants in the first slope gradually increased and already at the beginning of flowering in both varieties it was 88.3-91.1 cm against the background of liming and 92.7-93.0 cm of organic matter. The linear indicators increased accordingly to 92.1-92.6 and 95.2-95.7 cm when the plants reach the full flowering phase.

The best height parameters were obtained for a combination of two factors, where plant growth in both varieties was within 4.0-4.9 cm, or increased by 6.7-8.9%. It can be concluded that adjusting the terms of mowing grass contributed to its better development.

It was established that the first slope of the leaf-stem mass of alfalfa was formed due to the productive moisture of the autumn-winter period and a sufficient temperature regime for passing the stages of organogenesis. The plants produced a high yield of leaf-stem mass when the grass was mowed in the phase of beginning and full flowering (3-4 regimes) regardless of the level of fertilization. At the same time, it was the largest on the organic background of fertilizer, which was 27.6-28.3 t/ha in the Unitro variety and 28.4-29.2 t/ha in Rosana.

The dependence of the harvest parameters on the terms of mowing the previous slope according to the modes of use of the grass stand is established. With the alienation of alfalfa grass in the budding phase, in the second slope, the indicators were the lowest and amounted to 8.6 t/ha. An increase in productivity was observed under the second regime, up to 13.0 t/ha for mowing the grass at the beginning of flowering. The change in the mowing scheme of the grass stand within the regime affected the yield indicators of the leaf mass, which were determined by the height of the plants against the background of fertilization and the development phase of the alienation of the grass stand in the first slope.

Based on the analysis of the obtained data, it can be concluded that regardless of the change in the alternation of slopes according to the main phases of growth and development of the culture, its endurance and stability to produce regardless of the hydrothermal conditions of the growing season have been noted.