COMPARATIVE ANALYSIS OF METHODS OF DETERMINING LEAF AREA IN COCOA GENOTYPES

The knowledge of the leaf area is an important tool in the analysis of plant growth and development. Thus, the objective was to compare the methods, integrating leaf area, software DDA, software ImageJ and measurement of leaf dimensions, aiming to define the most appropriate correction factor to estimate the leaf area of cacao genotypes. The experiment was conducted at the Experimental Station Filogonio Peixoto in a randomized block design with four replications in a factorial arrangement of 4 x 8, being 4 assessment methods of leaf area and eight cacao genotypes (Common Variety; TSH 1188; Catongo; CCN 51; ICS 1; ESFIP 02; SJ 02 e PH 16). The results were submitted to analysis of variance and correlation and means were compared by Tukey test 5%. There was no difference between the methods of determining leaf area, being found positive correlation between the methods DDA, ImageJ and leaf dimensions with the integrative method of leaf area (default), with values of correlation coefficients (r) greater than 0,98. The genotypes TSH 1188, Catongo and CCN 51 have higher average leaf area. The methods tested were shown to be viable to estimate leaf area of cacao accurately, however, we found three groups of correction factors, being K = 0,682 for genotypes SJ 02 and Common Variety, K = 0,670 for genotypes CCN 51, Catongo, TSH 1188 and ICS 01 and K = 0, 655 for genotypes ESFIP 02 and PH 16.