Relationship between Leaf Area Index and Lysimetric Crop Coefficients of Pigeonpea (Cajanus cajan L.) under Local Climatic Conditions of Vidarbha

Abstract

The experiment was conducted to determine the crop coefficients and leaf area index of pigeonpea, using a digital weighing type lysimeters. The research was conducted under Department of Irrigation and Drainage Engineering, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola for kharif season of year 2024. The meteorological data was collected from the weather station installed at the experimental site to determine the reference crop evapotranspiration (ETo) using Penman-Montieth method. The crop evapotranspiration (ETc) was measured using water balance method by using weighing type lysimeters. Crop coefficients were determined for pigeonpea as ratio of daily ETc and ETo. Simultaneously, leaf area index was measured monthly using a leaf area meter. The study reveals that Kc values and LAI increased with crop development, reaching maximum during the mid-season stage and showed a strong positive correlation with each other with an R-square value of 0.78. The results highlight the importance of stage-specific Kc and LAI values for accurate irrigation scheduling and for improving water use efficiency in pigeonpea cultivation.