Andreea MÂRZOCA, D. MANEA, F. SALA* None florin_sala@usab-tm.ro
The study investigated the leaf area of Solanum nigrum L. by non-destructive method. Determining the leaf area based on leaf parameters and a correction factor is accessible, sufficiently accurate, and with minimal costs. To find out the correction factor, and to make the working model, the leaves were taken at random from different plants, the species Solanum nigrum L. The leaves were scanned (1:1 ratio). Images of the leaves were analyzed imagistically and scanned leaf area (SLA) values were obtained. The foliar SLA index registered values between 11.481 – 32.878 ± 0.967 cm2. The length and width of the leaves were measured for each leaf (L and w). The parameter L had values between 5.40 - 9.90 ± 0.206 cm, and the parameter w had values between 3.25 - 6.45 ± 0.151 cm. To determine the leaf area based on foliar parameters (Measured Leaf Area - MLA), a relation of type MLA = L · w · CF was used, where CF represented the correction factor for the studied specie. To find the CF, the scanned leaf area (SLA) was compared to the measured leaf area (MLA). The CF value at which the average of the errors had the minimum value (MEM) was considered optimal in the case of the analyzed samples. In the case of the studied samples, MEM = -0.036 cm2, corresponding to CF = 0.52. In the narrow range of calculations, the MEM values varied between -1.884 cm2 and 1.813 cm2, corresponding to the variable values of CF. The RMSEP parameter confirmed the optimal value found for CF (RMSEP = 3.86015, according to CF = 0.52). The MLA values obtained, at CF = 0.52, showed a normal distribution. The experimental data set presented statistical certainty, according to ANOVA test (F> Fcrit, p <0.001). The variation of MLA as a function of leaf length (L) was described by a polynomial equation of degree 2, in statistical safety conditions, according to R2 = 0.875, p <0.001. The variation of MLA as a function of leaf width (w) was described by a linear equation, in statistical safety conditions, according to R2 = 0.942, p <0.001.
leaf parameters, measured leaf area, model, Solanum nigrum
Presentation: poster