MORPHOLOGICAL FEATURES AND DRY MATTER PARTITIONING OF THREE BOTTLE GOURD (Lagenaria vulgaris L.) GENOTYPES UNDER DIFFERENT LIGHT LEVELS

A field experiment was carried out at the research farm of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka-1207 during February 2014 to June 2014. Low light responses of three bottle gourd genotypes (High-green, BARI Lau-1 and Local white) were investigated in the present experiment in terms of morphology and dry matter production. The light treatments consisted of (i) 100% photosynthetically active radiation (PAR) measured in the open field and (ii) 75%, (iii) 50%, (iv) 25% of natural PAR obtained by using mosquito nets of variable color and mesh number. Under shade condition the stem length, internode length, leaf area and SPAD values were recorded higher than control. But the stem diameter, leaf number and SLW were lower than control treatment. Under 75% PAR, all the genotypes of bottle gourd produced higher TDM than control treatment; but the highest relative TDM was recorded in BARI-Lau-1, which was followed by Local white genotype.  Result indicated that the fruit dry matter of BARI Lau-1 was more sensitive and Local white variety was less sensitive to low light.