Regularities of yield formation of switchgrass seeds in the conditions of Forest-Steppe of Ukraine

Abstract

The article focuses attention on the necessity of studying the peculiarities of the formation of switchgrass yield for providing productive areas with sufficient amount of seed material. An attempt to determine the dependence of yield on the elements of cultivation technology in connection with the weather conditions of the growing season has been made. The experiment on studying seed efficiency of switchgrass was carried out under the conditions of the Forest-Steppe using methodolo-gical recommendations of domestic and foreign authors. The yield of seed was determined by weighing method by weighing the seed material from each variant of the field experiment.

In our study we used both general scientific methods (dialectics, experiment, analysis and synthesis) and special ones, among them: laboratory – the determination of quantitative indices of plants (height and density of stems); field – determination of the interaction of the subject with the object of research; calculation-weight – establishment of seed productivity and yield of seeds; mathematical analysis of interconnections and graphical representation of data in the experiment.

 Complex influence of the cultivation technology elements during the contrast conditions of crop vegetation upon the switchgrass yield has been established. It has been determined that the weather conditions (average daily air temperature and rainfall) during the growing season influenced on switchgrass yield. The highest seed yield is formed by growing plants at a width of rotation of 60 cm, both wider and narrowed row spacings reduce this figure. The equivalent effect of biometric indices of plants (height and number of stems) on the yield of the seed of the switchgrass is determined. At the same time the application of spring crop yields to some extent offsets the negative effects of weather conditions.

 Application of fertilizers in plant cultivation with row spacing of 60 cm – from 0.57 t/ha to 0.72 t/ha has the greatest influence on swithgrass yield. Both increase and decrease of the width of row spacing leads to decrease of  crop yield. Swithgrass yield depends on the height of the plants by 25% under the coefficient of correlation r = 0.51 and by 23% – on the number of stems according to the correlation coefficient r = 0.48.