A non-destructive rapid method for estimation of leaf area in naturally grown Neem (Azadirachta Indica A. Juss.) and Pongamia (Pongamia Pinnata L. Pierre)

Abstract

Leaf area measurement can be a time consuming process and requires sophisticated electronic instruments. The objective of this research was to develop a simple, accurate, non-destructive and time saving predictive model for leaf area (LA) estimation in Neem and Pongamia. In the present study the authors have developed a regression equation (RE) and a fixed coefficient (FC) to calculate the LA of Neem and Pongamia plants of five year age class grown in natural conditions. The regression equation, Leaf area = L*W*0.6585 - 0.9828 for Pongamia and Leaf area = L*W*0.465x + 0.8781 for Neem was derived by taking actual leaf area as dependent variable and product of L and W, as independent variable (r = 0.97 for Pongamia and r = 0.86 for Neem.) The FC calculated by taking the ratio of actual to product of L and W was found to be 0.634 for Pongamia and 0.572 for Neem. The equation and coefficient was validated and was found significant. The study indicates that either FC or RE can be used with precision to determine LA of Neem and Pongamia grown in natural condition, non-destructively. This type of short cut, rapid method is highly useful when a large number of provenances are to be tested or in places where instrumentation facility is not available.