Effect of Light Intensity on the Morpho-physiology and Yield of Bottle Gourd (Lagenaria vulgaris)

This study was carried at the experimental farm of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh. Bottle gourd cv. High-green (hybrid) was grown to investigate the morpho-physiological changes and yield performance under four different levels of light (100, 75, 50 and 25% PAR). It was observed that some of the morphological characters like main stem length, internode length and individual leaf area increased, whereas main stem diameter and numbers of leaves per plant decreased due to the reduced light levels. At 50% PAR number of leaves per plant did not decrease significantly in bottle gourd. Leaf weight ratio (LWR) remained more or less similar up to 50% reduction of PAR. SPAD value increased with the reduction of PAR level i.e. partial shading stimulated chlorophyll synthesis in leaves. Compared to 100% PAR the total dry matter (TDM) did not reduce. Bottle gourd produced the highest yield (41.53 t ha ) at 75% PAR level and it did not 1 show significant fruit yield reduction at 25% PAR level compared to full sunlight. However, considering TDM and fruit yield bottle gourd and cucumber were found suitable for reduced light condition (up to 50% PAR).