EFFECT OF REDUCED LIGHT INTENSITIES ON GROWTH AND YIELD OF TWO CUCURBITS

Abstract

The experiments were carried out at the research farm of Sher-e-Bangla Agricultural University. Sher-e-Bangla Nagar, Dhaka-1207 to investigate the growth and yield performance of two cucurbits (viz, bottle gourd and ash gourd) under four different levels of light intensities (100. 75, 50 and 25% PAR).The experiments were laid out following Randomized Complete Block Design (RCBD) with three replications. After crop establishment, nylon nets of different sieve sizes were used to create treatments of different reduced light and light intensity was measured by a light meter. Morphological characters like internode length. and individual leaf area increased whereas number of leaves plani', branches plant" and individual fruit weight were decreased due to the reduction of light levels in the vegetables. At 25% PAR level, the number of leaves plant" decreased markedly in cucurbits, bottle gourd and ash gourd. Main stem length, stem weight ratio remained almost unchanged in bottle gourd and ash gourd under different light levels. Leaf weight ratio (LWR) slightly reduced in both bottle gourd and ash gourd. Compared to 100% PAR the total thy matter (TDM) of bottle gourd and ash gourd did not affected by reduction of light levels up to 75% PAR. The highest dry matter yield plant" (634.53 g and 556.47 g) were achieved from 100% PAR level in bottle gourd and ash gourd. respectively. At 100% PAR level, the fruit yield were 42.40 ha" in bottle gourd and 44.13 tha" in ash gourd. Significant fruit yield reduction was obscrvcd at 25% PAR in both ash gourd and bottle gourd. The bottle gourd provided significantly higher yield (52.42 t ha") at 75% PAR level compared to hill sunlight. The higher fruit yield was the product of higher fruit plant" and higher individual fruit weight. These results suggested that bottle gourd is more suitable as under storey crop compared to ash gourd.