Morphometric indices of plants as a basis for determination of biomass yield of switch grass

Abstract

Among the significant number of grain cereals used for the production of solid kinds of biofuels in the form of fuel pellets and briquettes as the acceptable raw material is biomass of switch grass, or “virgate millet”. The main purpose of the research was to substantiate a new approach for determination of the optimal seeding rate and calculation of the yield of biomass of switch grass by means of application of morphometric indices of leaf surface area and mass of the aboveground part, determining the statistical relationships between them. It is determined that the leaf surface area and the mass of the aboveground part of the switch grass consist of the sum of the plant area; mathematical calculations based on correlations were used to obtain it. The correlation coefficient between the surface area of the leaves on the shoot and its height is calculated. The maximum leaf area of virgate millet plants can be achieved at a seeding rate of 4.0–4.5 million seeds/ha, which makes it possible to form in the first year of vegetation 70–80 plants per linear meter. The height of the stem and the number of leaves on it has the greatest influence on the leaf surface area and the mass of stems of switch grass plants. The close multiple correlations between the leaf surface area and the mass of the stem and its height and the number of leaves on it make it possible to calculate the leaf surface area and stem mass based on morphometric indices of switch grass plants. The results of determination of the indices of yield formation of switch grass depending on the morphometric data of the leaf surface area and the mass of the ground shoot are presented.

Keywords

• switch grass
• solid kinds of biofuels
• leaf surface area
• correlations
• regression equations