Estimating Gladiolus leaf area by linear measurements

A non-destructive method to estimate leaf area was developed from linear measurements in four cultivare of Gladiolus: White Friendship and Friendship, under three NPK fertilization treatments, and Jester and Spic& Span, under four irrigation treatments. Plant material for leaf area determination was collected and measured at spike harvest; about 1200 leaves were used. On the basis of correlation and regression analyses, measurement of width alone or of length alone is not satisfactory (r = 0.877 and r = 0.929) whereas the leaf area can be predicted accurately according to the model area = 0.62*Length*Width (r = 0.982). The same equation is applicable to the four varieties, irrespective of management conditions and leaf size.