Relationship between leaf area, above-ground mass and morphometric indices in miscanthus

Purpose. The aim of the research was to create theoretical bases for the development of experimental methods for the determination of LAI and AGM by establishing the statistical relationship between LAI and AGM of giant miscanthus and ithe morphometric indices.Methods. Field, laboratory, analytical and statistical (correlation and regression).Results. LAI and AGM of miscanthus consist of the sum of areas or masses of shoots belonging to a plant. To determine the LAI and AGM of a shoot, mathematical calculations were used on the basis of correlations. It was established that the correlation coefficient between the leaf area (s) of a shoot and its height (h) is rsh = 0.878±0.048. Similarly, it was found that the correlation coefficient between above-ground mass of a shoots (m) and its height (h) is rmh = 0.898±0.045. In this connection, the relationship between LAI and the height of the shoots and the number of leaves on it is close (Rs.hn = 0.914) and significant (Ff = 246.5>F0.05 = 3.09), for the mass (Rm.hn = 0.910 at Ff = 232.3> F0.05 = 3.09). The dependencies of the LAI (s = 5.005h + 66.654n-569.586) and the AGM (m = 0.4186h + 2.7557n-37.8759) of the miscanthus shoots were determined from the height of the shoots and the number of leaves on them.Conclusions. The greatest influence on the leaf area and the above-ground mass of the shoots have the height of the shoots (h) and the number of leaves on it (n). At the same time, the coefficients of the pair correlation were rsh = 0.878 ± 0.048; rsn = 0.759 ± 0.066 and rmh = 0.898 ± 0.045; rmn = 0.689 ± 0.073, respectively. Close correlations between LAI and AGM and the height and the number of leaves on it, respectively, the coefficients of the multiple determination were R2s.hn = 0.836 and R2m.hn = 0.827. Dependences s = 5.005h + 66.654n-569.586 and m = 0.4186h + 2.7557n-37.8759, which make it possible to calculate leaf area and above-ground mass of the shoots based on their morphometric indices (the height of the shoots and the number of leaves on them)