Sorghum Leaf Area as a Function of Sixth Leaf Area

This study was undertaken to determine the relationship between sixth leaf area and total leaf area of sorghum ( Sorghum bicolor Moench) to obtain the total leaf area estimate without having to make the time consuming area measurement directly. Ten sorghum varieties were raised at Tamil Nadu Agricultural University campus Coimbatore from which the leaf samples were taken. The allometric relationship derived by logarithmic transformation between total leaf area (TLA) and sixth leaf area measured by leaf area meter (SLA_LW) and TLA and sixth leaf area measured by maximum length and width (SLA_LW) were not different significantly. The allometric relationship for all the ten varieties of pooled data were
TLA = 27.416 (SLA_M)^0.794
and TLA = 14.355 (SLA_LW)^0.857)
Where TLA, SLA_M and SLA_LW are measured in cm². The standard error of estimate equalled to 0.00299 and 0.0035 for the regression of TLA-SLA_M and TLA-SLA_LW respectively. The correlation co-efficients for TLA-SLA_M and TLA-SLA_LW were 0.94 and 0.93 respectively. Among the relationships tried for third, fourth, fifth, sixth and seventh leaf area by meter and length X width verses total leaf area, the SLA verses TLA found to be more suitable.